If #HurricaneDorian Hits as a Cat4, Still No Long-term Trends in Florida Major Hurricanes

By Dr. Roy Spencer from his website

Atlantic hurricane activity is notoriously variable, not only from year to year, but decade to decade.

In fact, based upon studies of overwash sediments in coastal lakes stretching from the Florida panhandle to eastern Louisiana, it appears that the period from 1,000 to 3,800 years ago had a considerably higher incidence of Category 4 & 5 hurricanes than in the last 1,000 years. These are admittedly indirect, proxy estimates, but if you read this American Scientist article, it sounds like the researchers have pretty strong evidence.

Why would major hurricane activity vary so much? No one knows. Our climate is a nonlinear dynamical system, capable of undergoing unforced changes both locally and globally. Atmospheric steering currents, wind shear, and African easterly wave activity all play a role in hurricane formation. Tropical Atlantic sea surface temperatures (SSTs) in the late summer are always sufficiently warm to support a major hurricane and are, in my opinion, overrated as a controlling factor. Factors other than SST tend to largely determine hurricane activity and strength.

More direct measurements of hurricane landfalls in Florida have only been possible in the last 120 years or so since prior to 1900 very few people lived there. Before 1900, the intensities of these storms at landfall were quite uncertain. It could be some even went unreported.

If we examine the record of major (Category 3 or greater) hurricanes at landfall in Florida since 1900, and assume that Hurricane Dorian strikes Florida as a 115 kt Category 4 storm, we see that there will still be no long-term trends in either the intensity or number of major landfalling hurricanes. (In fact, both trends are slightly downward, but not significantly so.)

If Hurricane Dorian makes landfall in Florida as a 115 kt Category 4 storm, there will still be no long term trend in Florida major hurricane landfalls since 1900.

This is not to say there won’t be potentially catastrophic damage. For example, the population of Miami in 1900 was less than 1,700 people. It is now 2.74 million. Needless to say, vast expanses of storm-vulnerable infrastructure has been built over the last 120 years across the Miami-Ft. Lauderdale-West Palm Beach metroplex, and northward along most of the Florida coastline.

But increasing storm damage does not mean increasing storminess.

126 thoughts on “If #HurricaneDorian Hits as a Cat4, Still No Long-term Trends in Florida Major Hurricanes

  1. All the headlines have already been written: “Hurricane (insert name) is just the latest example of Climate Change”. Any bets?

      • Roy what would a 1C rise in ocean temperature along the path of Dorian do to its intensity, say as a percentage increase?

        • It just might deliver it right to your front door Loydo. Notice the strategic placement of the qualifier MIGHT. Then again I Probably won’t. Loydo you are a hopeless irrational alarmist. That has watched to much ALGORE TV.

          Why, if a 1 percent rise in your mind is going to be catastrophic, do all are presidential types buy property on the water in the path of these horrible world destroying hurricanes? When Barack Obama, ALGORE, and the entire line-up for the Democratic Presidential hopefuls are convinced that the 1C rise is coming and have acknowledged that any action taken by Government can not prevent it. It is simply too late to turn them back. Doesn’t it strike you as odd that they would invest in property that puts them in harms way? What rational human does that?

          I think you need to petition the government to repossess all the property along the east coast and force all of us Evil Deniers to take up residence on the water. Of course most of the people who already own property would become deniers, if they aren’t already card carriers.

    • More likely: “Hurricane (insert name) made x% worse by climate change – attribution models.”

    • Richard

      You would never make a headline writer on the New York times. What you meant is

      “Hurricane (insert name)is just the latest terrifying manifestation of the climate emergency that has already seen millions made homeless.”

      now, do you want to try again, in your words?

      tonyb

    • Heck, I am not greedy.

      Can I just be the “house” and take a 10% vig on all of your winning bets?

    • Maybe Dorian will come ashore and wipe out the Obama’s new home.

      Now that would be a type of climate change.

  2. The narrative lately is to categorize storms as “the most deadly since….”, or “the most destructive storm since…” never taking into account that there are more people, and more structures to kill or damage. Death toll and cost in dollars are the new metrics for measuring storm strength.

  3. Much has been written about the application of the precautionary principle regarding climate change and its projected effects. However, it appears to be largely ignored by those choosing to invest in waterfront real estate in storm-vulnerable areas, even in the face of warnings that it is time to move to higher ground. Hmmm

  4. the hyping of this one will be incredible, places like here are the only place left to seek the truth……

    • ..the storms don’t drive people crazy…..it’s their crappy forecasts that do it
      They’ve had this thing from the Keys to South Carolina so far…no one knows what to do
      …missing the state…crossing the state…and going up the middle of the state

      • That is the nature of hurricane path forecasting. Subtle changes in surrounding air masses that cannot be predicted cause such uncertainty. The ECMWF model, one of the most accurate, is forecasting the path based on the western Atlantic high pressure ridge remaining strong and steering the storm farther south than the GFS model which is based on a weakening high pressure ridge. Which ever way the ridge goes, when ever it does, that will fine tune the forecast. If the ECMWF turns out correct, the storm will pass much closer to me so I am being cautious and preparing for that scenario.
        Prepare for the worse and hope for the best.

        • And the exact timing of various events has a huge effect on the path of the storm, and even the trajectory.
          It is a chaotic situation, in which the hurricane can influence what happens elsewhere, or not.
          It may in fact be impossible to predict some storms in some situations, no matter how much computing power and data input to start with.
          The intensity, the size of the wind field, the timing of the tides, the timing of the eyewall replacement cycles, upstream weather coming into play…
          So many factors are important regarding how destructive or not it is, and with myriad interacting factors combining in unpredictable ways, where exactly it makes landfall.
          And when.
          Forward motion velocity will impact which factors will or will not have time to influence the path and intensity.
          I expect the next 24 hours are going to determine if it hits Florida, and perhaps exactly where and how strong it will be.
          There is a narrow area of wind shear ahead of the storm, which I am looking at very closely.

      • sad part is they do it every year for every storm, even tropical storms. As soon as one kicks up out in the Caribbean or the Gulf they commence with throwing darts at the map & getting the public all worked up & in panic mode. If they haven’t already, soon they will be urging evacuations to that wonderful parking lot otherwise known as I-95. They can’t possibly know with any certainly more than 2 days out where this storm will actually go or how bad it will be.
        I’ve watched them do it for the 12 years I been down here & it never fails to amaze me

        • Yes but two days for everyone to get their prep done is not feasible. Obtaining supplies that you will use in any event like gas & water should be taken care of first. Then resupplying your hurricane stash, then when you know it is getting close you have to attend to your property and make sure everything that can fly is put away or battened down. Shuttering up is the last thing you do but you need to have completed everything else first. I think most of us who have been through this many times have a good sense of what the timing is for all these tasks and go about them in a neat and orderly way without panic or worry. You can never over prepare because, like Israel, one wrong mistake and you are done for.

          • People need to make plans for pets, medications, supplies, where to go and when.
            There are many old people, hospitals and other caregivers, shelters must be open and emergency plans put into place, employees dismissed from work so they can prepare.
            Even if the people responsible for the safety of others knew when and where a storm will hit, and how hard, what to tell people and when to tell them would still be second guessed and highly debatable.
            The only thing that bothers me is when stats get exaggerated and uncertainty poorly stated.

        • To some extent they have to do what they do they way they do it.
          It is a damned if they do and damned if they don’t situation.
          If everyone was always paying attention and knew what level of preparedness was appropriate at every stage of risk and uncertainty, that would be great.
          None of those things are true.
          No one even knows what the level of risk is, nor how uncertain the forecast plots are, until afterwards.
          The cone of uncertainty covers the whole state at this point…meaning that there is a 67% chance that the average error over the past five years in predicting such storms will be within the cone.
          That is all it means.
          Most people could never be persuaded to pay enough attention to even be able to try to explain exactly what they means and what the implications are.
          At some point a very powerful hurricane will impact a large coastal city in Florida, directly and at a 90° angle.
          This could be the time.
          Should they wait until they know where it will go, exactly?
          No one will know that until it hits.

          • Let me try that sentence again, the one that starts with “most”: Most people could never be persuaded to pay enough attention to someone trying to explain this, to even have a chance of grasping exactly what those cones means and what the implications are.

            A lot of people think the cone is the size of the storm, others think the center of uncertainty is the “real” prediction.
            These may be the people that think there is no reason to mention things like error bars because the center line in the grey area of uncertainty was the “actual” temperature.
            And the ones that figure than averaging 1000 worthless climate projections has a high likelihood of being what is actually gonna happen.
            Also that having 3,650,000 readings from 1000 locations on 36500 days means that you can use statistics to determine the temperature of a planet to within less than 1/100th of a degree, even though the thermometers used for many of those readings were only read to the nearest whole degree.

    • Thanks for the map! I’m more interested in that big wad of cloud cover in the Midwest, which seems to be heading my way.
      Plenty of rain last week made my lawn flourish and now I have to mow it, but should I wait a day or two? Hmmm….. One last mow before the leaves fall in autumn and I can mulch them to provide fertilizer to the lawn for the winter.

  5. Somewhat confused by the data on the NHC web site. They show the storm hitting the coast Monday morning as a major storm. Yet the hurricane wind probabilities show less than a 50% chance of seeing hurricane force winds. I get the plurality of most probable might not be greater then 50%, but even current position and speed isn’t showing closer to 100%.

    • There is a high probability of hurricane force winds somewhere along the Florida coast, and their forecast track shows their current best estimate of where that will be, but given forecast uncertainties in landfall location, the probability of hurricane force winds at any given location is still relatively low.

    • Measured data are, apparently, irrelevant to the NHC. Hurricane Barry (the first “hurricane” of 2019) was declared a hurricane, not by measured data, but by probability.

      • Remember, these are the same people that told us the year following Katrina would be disastrous, when it ended up being a total fizzle for major storms. Throwing darts sounds about right.

        That was one of the first major incidents that made me understand how important the concept of cui bono (or if you prefer, “follow the money”) is.

        • Those were for the most part not weather forecasters and they were not predicting weather.
          Unfortunately for a lot of people who need to buy insurance, those people got a lot of press and a lot of people overpaid for insurance, and several companies left the state for many years.
          Then again those two years proved that the statistical models used by underwriters did not have long enough tails on the high end.

          • Sorry Nicholas, but I could use some clarification on your reply if you have a moment. I was referring to the NHC in response to @icisil above, and am not sure what you mean. The NHC told the world it would be a bad year, and it was a nothing year. They did it again the next year, and again, a below-average year. It’s all archived: https://www.cpc.ncep.noaa.gov/products/outlooks/hurricane-archive.shtml, but I get the feeling you know all this and I’m just missing your point. I think they had the agenda dictated to them and even if I’m wrong, their predictive ability is nonexistent and the money spent on them could certainly be better spent elsewhere.

          • William Grey was an actual scientist and knew what was likely to happen. In fact he was largely correct about the bad years and that there would be a lessening of the favorable conditions.
            He was removed from his position prior to this occurring.
            When I say “they” (the ones who came to have authority and a voice)were not weather forecasters, I mean they had no skill…they simply projected a straight line onto a cyclic trend, and imagined they could not be wrong.

      • What you are saying is not what WOB and Roy were talking about.
        Exactly what is meant by the cones and the uncertainty boundaries is complicated and specific and not intuitive or obvious to many people.
        The cone of uncertainty five days out is very wide, and forward progress over the five days is itself uncertain given that forward speed can and often does change unpredictably.
        This storm has an excellent chance of being the worst storm to hit South Florida in our lifetime.
        Extremely powerful storms can and do occur, and when they do people die.
        Grousing about fudged stats is a different set of concerns than trying to determine what the level of risk at the present time for a particular person happens to be.
        I am hoping for the best, but the fact is South Florida and especially the East Coast has had a very long run of very good luck. Most places have anyhow.
        I have wondered every year around this time when that lucky streak will end.

        And even the places that got hit in 2004, and 2005, and most people hit in 2017…those were far from worst case scenarios. For most people. For some, it could hardly have been worse.

        I doubt this will be a worst case scenario, at least I hope the proper conditions are not in place, but no one knows that.

        There are many millions of people in a very precarious and uncertain situation at the moment.
        I think it is a good time to try and be helpful, for anyone who knows enough to be helpful or has enough insight to make pertinent comments.

        • “…This storm has an excellent chance of being the worst storm to hit South Florida in our lifetime…”

          By what metric? Nobody is projecting a Cat 5 (like Andrew was in 1992), and the projections seem to be narrowly targeting further up the coast than “South Florida.”

          Sure, there’s lot of uncertainty with both. But where does “excellent chance” come from?

          • The models are showing a lot of variability at the present time.
            A few outliers show the storm curling to the right and out to sea, and a few had a run that for a time showed the storm going straight west over the Keys and hitting Texas.
            The most likely is only that, and only as it appears at present.
            But the cone represents only 67% of the average error over just the last 5 years.
            Which means a 1 in 3 chance of a outcome outside the range of that wide cone.
            The situation will solidify as the storm draws nearer.
            Right now the forecast has shifted south from what it was when I went to sleep last night.
            But uncertainty remains.
            A few models showed for a number of runs that a cat 5 would emerge just prior to the time of projected landfall.
            Right now the situation for me personally is looking rather bad…worse than last evening.
            Keep in mind that a storm surge in the tens of feet, and imbedded tornados, will make it a worst case for some people…destroyed is destroyed, and dead is dead.
            So it hardly need to be the most powerful storm ever to be very bad for a lot of people.
            A hit at a direct angle at high tide (a King tide, as the Moon is near to being new) by a strengthening storm with the right front quadrant aimed at a high concentration of people…this will be very much worse than anything seen in these parts for a long time.
            Naples, which was wiped out by Irma, is a sleepy bedroom community compared to the east coast near Fort Lauderdale.
            And the value of beachfront estates in Palm Beach is very high.
            There are many very bad scenarios.

          • “Excellent chance” means it may well happen, although of course we hope it does not.
            I for one do not suppose or expect that the worst storm in a long time will have the highest certainty ahead of time.
            Irma had an excellent chance, and it was lucky for a lot of people…not so lucky for others…they way it played out. A turn a few hours earlier would have brought the worst of it into the highly populated East Coast, instead of the middle Keys and sleepy Naples.
            I suspect that few outside of Naples and SW Florida have any idea how bad it really was down there.
            It was bad.
            Really bad.
            There were no National News reports from the scene afterwards (well, there may have been a few…I lost power and internet and even most phone service just as the storm was hitting the Keys, and was unaware of where it was even as the eye approached my neighborhood.
            Luckily I spent years in construction and chose a good strong house in the highest land in Lee County. Automatic storm shutters…etc.
            I will spend the next few days cutting trees down or back, and removing limbs and fronds where I can.
            My Royal Poinciana trees that were shredded and now bigger than ever, and I now know they are very brittle.
            I found branches as big as my arm around, and weighing hundreds of pounds, had blown clear over my house and were imbedded in sand about a foot, with a spear tip where they sheared of from the tree trunk.
            And that was only about 100mph, not including the imbedded tornados.
            I slept through the eyewall after my cat came home in the midst of it and I relaxed.
            I did not even hear it when a 60′ Bismarck Palm landed on my roof and stopped, right above where I was sleeping.
            Let’s hope building code improvements have been effective.

          • As to “no one”, it is true most models have stopped predicting cat 5 intensity, but there are these:
            http://hurricanes.ral.ucar.edu/realtime/plots/northatlantic/2019/al052019/intensity_late_stream15/aal05_2019083000_intensity_late_stream15.png

            And every model run only uses the info at the time the run starts.
            They have drawn back, but just as they have mostly coalesced around Cat 4, that does not mean they are bound by some physical law to be right, or to not change again for the worse in the next 2 to 4 days.
            So…some are.

          • Also, Andrew was quite potent but very compact.
            This one might not be when and if it gets here…and Homestead was mostly plant nurseries and farms and some modest housing communities.
            Not exactly Fort Lauderdale or Boca Raton.

          • Nicholas,
            If Dorian comes ashore in Florida as a Cat 4, rest assured that NHC “experts” will revise it upwards after the fact 6 months later to a Cat 5.
            Just like they did with Hurricane Michael.

          • Nicholas McGinley,

            Correct me, if I’m wrong, but isn’t the “King Tide” a twice-a-year event, because it requires the Earth to be at perihelion (closest to the Sun), which happens only twice a year, January and July, as well as the Moon being at perigee? The Moon is at perigee every 14 days, but we don’t use the term “King Tide” to represent the tides’ size 26 times throughout the year.

          • Justin, Earth perihelion occurs on 1 time per year IAW Kepler orbital mechanics. Around 2-3 January right now I think.

          • Preaching so much uncertainty and “a lot of variability” but then stating there is an “excellent chance” was silly. Not that you defined “excellent chance” as a specific probability, but that conveys something pretty substantial.

            No, Naples and SW Florida didn’t get the attention post-Irma that they should have. Weather Channel was live in a Ft Myers parking lot, including as the eye went over as I recall, but there was very little attention paid to Collier County in the aftermath (or parts of central FL that were hit pretty hard).

          • Well Michael, the strom is now 185 mhp sustained and a central pressure of 910 mb. Gusts to 220 are the reports. On satellite pics it looks monstrous.
            It is heading due west with no sign of even slight deflection to the north. A few models are continuing to predict a direct hit.
            And the storms are not constrained by the models.
            After all, the models all said it was coming straight in, now most say not, but who is to say that will not change?
            Again…zero indication of any hint of north turn. I sure hope it does, but at a certain point these things have so much momentum they ignore steering factors that others storms het redirected by.
            Andrew was also predicted to curve to the north.
            And the most likely guidance now has this thing coming up to the coast and then taking the eye north along the coast.
            The center line of the cone of uncertainty may be where the storms goes, but a few days before Irma hit, forecasts and models all shifted to have the thing going up the East coast offshore.
            Giant cat 5 monster heading straight for Florida and now in the Bahamas, but yeah, I was completely full of shit to express uncertainty or assert that there was an excellent chance of a worst case scenario.
            What does “excellent chance” mean?
            Maybe it means the best chance of a catastrophic outcome I can recall.
            No turn yet, cat 5 even though “no one is predicting it”, except may a few people who cautioned that nothing should be taken for granted.
            Notice the headlines: The storm has not wavered, only the models and forecasts have, but the headlines scream that the storm has taken a course away from Florida, or words to that effect. A few models have said all along it would be cat 4.
            It appears to have strengthened long before getting to the Gulf Stream…right at the time Joel said to be on the lookout for rapid intensification.
            I do not think I am preaching anything Michael.
            I think you are projecting.

          • I missed that one of your objections to my comments seems to have been regarding the nature of what specific and exact area counts as “South Florida”>
            I am curious about another thing, now that I have thought about it for a minute: If it was “silly” to say there was an excellent chance of something happening, and then it does, even though someone might have said it was silly when I said it, and only true later, who is right?
            Was I?
            If “no one” was projecting a cat 5, and then it is one, and in fact the very strongest hurricane in modern records in this part of the ocean (northern Bahamas), was it still “silly” of me to caution that worst case scenarios are possibl?
            When hurricanes are heading in the general direction of an area, even when modeling does NOT show highly variable outcomes that keep changing, then in my estimation it becomes an excellent chance. Hurricane is formed and heading in the proper direction and conditions and climatology favor intensification.
            When is expressing an understanding of the range of outcomes not “silly” Michael?
            When is pooh poohing risk, when it is well known that only rarely are the intensity and path of hurricanes anticipated with anything that could be called accuracy or confidence, itself somewhere between silly, really dumb, and head up your #&%?
            Several days after saying “This storm has an excellent chance of being the worst storm to hit South Florida in our lifetime” in an off the cuff comment, we have the strongest storm ever to be measured in that location with modern instrumentation, and it is heading on a direct path towards…um…Sough Florida.
            Projected by most models, at the present time, to curve away either just as it approaches the coastline, or right on the coastline, or right after making landfall, then slowing and heading north.
            Of course that is still several days out.
            Can a storm speed up?
            Can new factors come into play?
            The more time goes by the more old projections are worthless.
            I can recall several instances of hugely powerful storms ignoring projections and the explanation later given is that large enough storms simply have enough internal energy and momentum to make their own steering.
            If this one forgets to turns, a lot of people will die.

    • WOB,
      What you are not taking into account, it appears, is that the center line within the cone of uncertainty is not a prediction of the place the storm will hit.
      Rather, it is the center of a wide area of uncertainty.
      Based on the amount of error that has been the average for the past five years this many days ahead of time, there is a 57% chance the storm will be inside that cone at that time.
      1.3 of the time it has been somewhere else.
      This thing could still go south of Florida or curve out to sea. But most models and so the official forecast is where we see it.
      This can change and often will.
      The only thing worse would be just looing at a weather map and trying to guess, like in the old days.
      But back then people knew they were not doing anything other than guessing.

  6. >>
    Our climate is a nonlinear dynamical system, capable of undergoing unforced changes both locally and globally.
    <<

    Which they ignore when discussing the relationship of CO2 to climate. (It’s also a chaotic system. Nonlinear systems tend to act that way.)

    Jim

  7. From the article: “Tropical Atlantic sea surface temperatures (SSTs) in the late summer are always sufficiently warm to support a major hurricane and are, in my opinion, overrated as a controlling factor. Factors other than SST tend to largely determine hurricane activity and strength.”

    An excellent point. All the alarmists talk about is sea surface temperature. Nothing else exists to them.

    • More important that the surface temp, besides for all of those other factors (which I have for years brought up in every discussion about storm frequency and risk on a warmer planet), is the depth of the warm layer.
      Forward speed of the storm combined with the depth of the warm water layer can be critical once a storm forms.
      A slow storm over a shallow layer of warm water may run out of warm water.
      But that is perhaps less likely with the Gulf Stream between the storm and the coast.
      Hurricane researchers learn more about how these storms behave and the various factors that influence them with nearly every major hurricane.
      Incorporating that info into models and into forecasts is difficult and not so simple.

  8. What happened to Hurricane Michael in 2018? It made landfall at the FL Panhandle at a Cat.5 I thought.
    I wish the best for everyone in Dorian’s path, but it doesn’t look good.

    • Michael’s highest land-measured data at land strike suggests a category 3, max. CAT 5? No way. NOAA has changed how they categorize hurricanes (cool the past, warm the present).

      • Yep. They no longer follow the criteria of the Saffir-Simpson scale. These days they use unsustained max short burst wind speed at flight altitude and then “extrapolate” that figure down to ground level. Actual ground level measurements are never as high as the figures they tout. This has been an ongoing issue with every hurricane over the recent years.

      • Keep in mind US land-based stations use a 2-minute average for determining sustained wind. Hurricane folks use a 1-minute average. So it’s much easier to get a 1-minute sustained wind of 140mph than it it to get a 2-minute average at that speed. I think the conversion factor is the peak 2-minute wind is 0.93 of the peak 1-minute wind. So the bottom line is land based stations will always under-report the sustained wind vs. the hurricane center. I’m not saying that Michael was or wasn’t a Cat 5, but this discrepancy is a consideration.

    • There was no barometer reading that was anywhere close to what is required for Cat 5 winds to be present.
      I hope that over time this crap they are spewing about Michael will be reconsidered.
      Which can and does happen.
      Assessments go on for past storms for a long time in some cases.
      But for sure, it is physically impossible for Michael to have been a Cat 5, unless they change the criteria.
      Wind speed and barometric pressure are highly correlated in hurricanes.
      Physics is still a thing.

        • There were many photos of damage showing some houses wiped from their foundations, and a few right on the beach that were untouched. And in the background of the pictures and video of the worst of the damage, not a quarter mile away, were many regular buildings that looked to be completely intact.
          No doubt building codes explain much of this, but as you point out, flimsy nonstructural components are unlikely to have stood up to a direct hit from a cat 5 coming ashore a few hundred feet away.
          We have all seen what it looks like when a cat 5 hits directly.
          Storm surge tens of feet high many miles inland.
          Now, if the storm intensified just prior to landfall, that could explain minimal evidence of surge.
          But the barometer?
          The pressure drops first…and the wind responds to the drop in pressure.
          Also, imbedded tornadoes do not get counted, or should not be, along with hurricane intensity. So isolated pockets and even long stretches of severe damage can occur and not indicate hurricane intensity.
          I recall driving up I-95 with a truck load of plants, from Central Florida to Philly, just after the interstate reopened after Hugo.
          Hundreds of miles of large diameter trees snapped like toothpicks every which way, like the Jolly Green Giant smashed his fist on them…one broken to the north, next to it one broken to the south and another to the east. On and one, and it was in inland SC & NC very far from landfall. Every sign was down, even the tiny mile marker signs were pressed flat to the dirt for a hundred miles or more. Steel pole, sign about 4×8 inches, pole bent flat. That is strong wind…and it was nowhere near cat 5 even at landfall.

  9. Listening to a storm expert talking on CNN. The host asked if this storm was another sign of climate change. The expert said no. This is the usual activity for this time of year.
    See, there’s hope.

    • The guy who said that was a weather forecaster with an understanding of hurricanes and such, and he has absolutely no future in the climate change racket.

    • So much of the population is already brainwashed. I saw a twitter nitwit say that this storm was “uncharacteristic” in that it was “flooding areas that normally didn’t flood”…on Grand Bahama Island. Holy hell.

  10. “But increasing storm damage does not mean increasing storminess.”

    Precisely what the doomsayers ignore. In fact they assert that the increasing storm damage in $$$ is the proof of climate change.

    • If the hurricane were to hit an undeveloped shoreline does it still do damage?
      How would the damage be measured? How do we know it’s not shoreline improvement or corrections?

      • Most of the inlets in the barrier islands can be traced to individual hurricanes in the recorded past.
        Imagine a new inlet forming during a hurricane, centered right in West Palm Beach.
        It is not impossible.
        Open water where vastly expensive real estate now sits…
        Barrier islands are basically sandbars left by strong coastal storms.
        They can and do come and go, and I suspect it matters not what is built there.
        Looks like we could have an ACTUAL Cat 4 storm (maybe worse…who knows…they are only computers) headed for highly populated real estate on low lying South Florida.

  11. My Atlantic-basin Hurricane-Geomagnetic Link Rapid Intensification hypothesis is in play with Dorian.

    The current ENSO 3.4 index is well below +/- 0.5 C, which is the first requirement for the Ap-hurricane rapid strengthening linkage to hold up.
    (that is, an ENSO 3.4 value > (+/-) 0.7 completely destroys the correlation).

    The current Ap index is staying below 20, with all the station K indices staying at 0 or 1.
    https://www.swpc.noaa.gov/products/station-k-and-indices.

    My hypothesis predicts that if the planetary K index ≧ 4, (which is Ap ≧20), then Dorian will simultaneously undergo a period of rapid intensification.

    Rapid intensification (RI) is a NOAA/NHC defined term: A central pressure drop : a drop of 1.75 mbar/hour or 42 mbars in a day.
    See here for a discussion of hurricane RI:
    https://hurricanes.fandom.com/wiki/Rapid_intensification

    K and A index spikes are forecast to happen late on the 31 August, 1500- 2400 GMT.
    Due to the very large Earth-facing Coronal Hole 935 particle stream arriving at 1 AU.
    http://www.solen.info/solar/images/AR_CH_20190828_hres.png

    see here for SWPC geomagnetic forecast:
    https://www.swpc.noaa.gov/products/3-day-geomagnetic-forecast

    Here is the text format of the 3 day SWPC geomagnetic forecast:

    :Product: Geomagnetic Forecast
    :Issued: 2019 Aug 28 2205 UTC
    # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
    #
    NOAA Ap Index Forecast
    Observed Ap 27 Aug 010
    Estimated Ap 28 Aug 005
    Predicted Ap 29 Aug-31 Aug 005-008-020

    NOAA Geomagnetic Activity Probabilities 29 Aug-31 Aug
    Active 15/25/28
    Minor storm 01/05/35
    Moderate storm 01/01/15
    Strong-Extreme storm 01/01/03

    NOAA Kp index forecast 29 Aug – 31 Aug
    Aug 29 Aug 30 Aug 31
    00-03UT 2 1 2
    03-06UT 2 1 2
    06-09UT 1 2 2
    09-12UT 1 2 3
    12-15UT 1 2 3
    15-18UT 1 2 4
    18-21UT 2 3 5
    21-00UT 2 2 5

    So based on my hypothesis prediction, look for Dorian to undergo a RI episode on late 31 August into 1 September (that is, Saturday night to the early hours Sunday morning) in conjunction with the forecast geomagnetic disturbance.
    Dorian will about 200 to 100 miles east of Great Abaco Island, Bahamas at that time with current forecast tracks. This will deliver a devastating strike to Little Abaco Island on mid-day Sunday.

    • Latest update shows the storm slowing and the time of landfall if it goes where it is currently anticipated, to be pushed back yet again.
      It is now predicted to be at the coastline North of Fort Pierce at 2:00PM Monday.
      This is awful news for people further north, although still only an iffy forecast four days out.
      But having more time to prepare is rarely a bad thing.
      We had a week ahead of Irma. In that week the projected path varied back and forth and caused a lot of people to lower their guard.
      I am looking at the intersection of the 70°W Longitude, 25° North Latitude point as a reference. To the right of that and South Florida risk is greatly diminished.
      To the left of it by a substantial margin, and it remains a huge wild card who is getting it.

      I am starting to see spaghetti plots with the storm missing the peninsula and passing over the keys and hitting Texas.
      But at the same time more of them have the storm curving out to sea.
      I would not want the job of trying to guess where such a storm will go.
      My approach would be to emphasize the risk and the uncertainty.
      However, forecasters and emergency planners have noted that when uncertainty is stressed, people tend to take that to mean risk is diminished and tune out.
      Peoples can be cray cray.

      • “…We had a week ahead of Irma. In that week the projected path varied back and forth and caused a lot of people to lower their guard…”

        Who lowered their guard? People on both coasts of FL evacuated painstakingly to Georgia and Alabama. I doubt FL has ever evacuated on that scale.

        • You did not hear about the thousands of people who got stuck in traffic jams that went on all day, ran out of gas and could not get more, etc?
          After having about the longest time to prepare that I can recall.
          Several times the forecast track had the storm path switch from the East of the peninsula to West of it and to the center of the state, and back again.
          Very little emphasis was given to how likely forecast tracks and cones of uncertainty are to change over time, and especially more than two to three days out.
          I did not say everyone stopped paying attention, or that no one did anything.
          I do not know how you missed the stories of the jammed interstates and side roads all the way to Georgia, and gas stations with either no gas or no one working or both.
          Now let’s turn it around: When you say painstakingly evacuated, who do you mean?
          Who evacuated and made it all the way out of the state?
          Millions of people were caught in floods, endured weeks with no power, roads with no traffic lights, closed stores or open ones with empty shelves and critical supplies being delivered haphazardly, and the stores refused to tell anyone what was coming or where or when.
          The National Guard was set up in my neighborhood distributing MREs and water for nearly a month. It was over a week before anyone was allowed back in some areas, so I know they did not leave and come back and sit in a flood with no food or power.
          Me…I sat it out in my cozy safe house, slept through the worst of it, and went outside in the morning to see the yewall had passed over my house, a tornado had missed my house by about thirty feet but many were not so lucky, and spent days helping people clear downed trees so they could escape being trapped.
          For one friend of a friend whose husband had jus dies, I spent hours just tryin to find a route to her street that was not flooded, and then several hours sawing and dragging trees from her road and then fixing a window that had blown in during the storm that she spent half the day and all evening leaning against to prevent her home from being wrecked and flooded.

          ?
          So, to answer your question more succinctly: Lots of people. But not everyone. Apparently.

          And there have been plenty of large evacuations over the years, several of which resulted in more deaths and misery than the storm.

          • People were raiding shelves and stocking up on gas several days before Irma here on the Gulf side…when the storm was supposed to hit the Miami-area.

            There was an “Oh crap” moment when the projected path switched from the east coast to the Gulf side. You can’t evacuate the entire state in a matter of days. Lots of people evacuated from Miami/FtL to Tampa only to have to evacuate again.

            I knew people who ended up driving from South Florida to hotels as far away as Huntsville, AL. The return drive to FL was a clusterf*ck as well for the people who evacuated.

            Exactly how quickly and how far in advance do you expect people to leave, and how smoothly do you expect it to go with such a large population and relatively narrow evacuation path? It isn’t always an option for some people to leave in the first place.

          • I am not expecting anything.
            And I know very well exactly what happened, right up until I lost power.
            You have an amazing propensity to put words in peoples mouths while saying things that are not true.
            I have not seen one single constructive comment from you, no explication, no weather details, no information, all criticism.
            What exactly is your point?
            That is it wrong to say that an uncertain situation is uncertain?
            If you are so smart, who do you think should evacuate, and when, and who should stay put, and where will it go, and how strong will it be, and when will it get there?
            Do you have anything informative or helpful to say?

    • The latest Ap/Kp forecast that now includes Sunday 1 September now forecasts the Ap spike even higher on Sunday with a Kp of 6.

      NOAA Kp index forecast 30 Aug – 01 Sep
      Aug 30 Aug 31 Sep 01
      00-03UT 1 2 6
      03-06UT 1 3 5
      06-09UT 2 2 5
      09-12UT 2 3 4
      12-15UT 2 3 3
      15-18UT 3 4 3
      18-21UT 2 5 4
      21-00UT 3 5 4

      Ap will probably hit > 20 on Saturday, and up to 40 on Sunday.
      This will be good test of my hypothesis – whether it is falsified or supported in prediction mode for a Dorian RI episode on Saturday into Sunday.

      • This is very interesting and I will be watching closely.
        The thing is, the storm will at that time just gone past the unfavorable slice of wind shear, and will be over the very rich and deep and fast flowing stream of hot water called the Gulf Stream.
        I am curious:
        What is that index and what does it measure, and how is this thought to influence hurricane intensification?

        • Nicholas,

          The K and A geomagnetic indices are measures of the variation in the horizontal component (in nanoTesla (nT)) of the Earth’s magnetic field measured at different stations over 3 hour intervals, 00-03 GMT, 03-06 GMT, 06-09 GMT, …, 21-24 GMT. The K index is quasi-logarthmic. The A index is linear scale that maps to K scale.

          For details on how all this works, go to this link:
          https://www.swpc.noaa.gov/products/station-k-and-indices
          and scroll to bottom, and click on the “Details” tab.

          The problem with my hypothesis is that (even it is correct) it is only still a correlative link. There is no physical mechanism that is clear to me. I don’t even know if it is actually changes in the Earth horizontal magnetic field that is affecting the hurricane’s and thus an RI. That ‘s becasue there’s a lot more going on “under the hood” of the geomagnetic sheath and the ionosphere surrounding the Earth during geomagnetic storms than merely a magnetic deflection measurable at the Earth’s surface.
          Geomagnetic disturbances are a manifestation of two other very real space weather phenomenon enveloping the Earth.
          – Solar wind speed changes (think of this as wind gusts during a steady wind that shifts up and down in speed over hours, and how wind gusts kick-up dust storms and move trees as an indication of that flow of air molecules, air flows which we can’t see unless there is smoke or other particles presents as an analogy of what is happening in Space.)

          – Particle fluence. That is electrons and proton fluxes, measured as particles/(cm^2 s sr) changes. The solar wind is actually just solar protons and electrons that were ejected from the Sun’s corona, but there movement carries a magnetic field with them that interacts with the Earth’s magnetic field.
          So K and A indices are actually an indication of 3 very different physical measures of solar wind activity hitting the Earth.

          And the K and A indices only measure the horizontal component of the geomagnetic field changes at the surface, but a hurricane in a complex structure that extends into the lower stratosphere. Does it have connections to the ionosphere? I don’t know.

          Further, for whatever reason, this correlative linkage only appears to operate on Atlantic Basin hurricanes from the limited Pacific data I’ve studied. Why not Pacific hurricanes and typhoons??? I don’t know. Maybe the data there isn’t as high a quality as the Atlantic hurricanes? Maybe the mechanism linkage is much weaker over the much more open Pacific??? I don’t know.

          The bottom-line is the mechanism is completely unclear to me.

          • Hmm.
            There is much we do not know, that much is clear.
            At some level, some questions are like trying to determine mathematically where the puck will end up in Bob Barker’s Price is Right game with a series of pins on a vertical surface.
            One thing I had noted for several years was many tropical systems have almost zero lightning, and I thought this was an interesting question as to why.
            But then a few came through with plenty of lightning.
            This time of year even a smallish pop up towering cumulus can have lightning before the first drops of rain hit the ground.
            It was likely due to the clouds being mostly wv with little or no ice crystal cloud regions.
            static charges between ice crystals is a good candidate for the buildup of charges in a T storm.
            But what about reverse polarity lightning?
            And lightning as seen from space where one strike triggers a series of strikes for thousands of miles along a front?
            Gamma radiation & antimatter particles from t storms, , upwards directed phenomenon like Sprites and Jets…these are not simple static charges of a localized nature existing within the clouds.
            And not only did no one predict any of this before they were observed, but the top people scoffed at the possibility after these things were reported…right up until they were filmed, or in the case of the gamma and antimatter (positrons), confirmed by NASA.

            I have been skeptical of people who predict Midwest US droughts based on solar cycles, but mainly because the drought was contemporaneous with nearby areas of excessive rains.
            IOW…alterations in typical weather patterns diverted moisture for an unusually long time.
            Why the Midwest? Why the nearby floods if it was the Sun?
            The whole planet faces the Sun.
            But good science proceeds by people making informed speculations, and then remaining open minded while looking for evidence of predictions based upon the hypothesis.
            I doubt I will be able to stay paying attention to blogs and news once the storm is upon us, and I know I will lose power, and even my generators all working perfectly will only mean I am comfortable and safe…it will not give me back internet once the trees start falling and power begins to go out.
            Still hoping this one finds a way to fizzle or miss, but it is not looking so likely that will happen, and every hour with the storm following the predicted trajectory and intensity guidance, brings it closer to land and fewer places it can go with no devastating effects.
            $hite is getting real in South Florida…but at least the timeline is being extended. Although that may give it more time to strengthen.
            Yesterday afternoon the wind here in SW Florida shifted to from the NE, which means there is now a vast wind field which can contract and has a huge reservoir of angular momentum lined up for adding to the storm if it pulls it in.
            Still poor outflow characteristics in some quadrants, but that is changing. CDO is now very symmetric on visible wavelength views. Outflow to the SW will ventilate the strom very well and set the stage for rapid intensification. This will happen today perhaps.
            But there is still considerable divergence in models, although the outliers may be ones known to have poor skill for this sort of event.

            https://www.star.nesdis.noaa.gov/GOES/sector_band.php?sat=G16&sector=car&band=GEOCOLOR&length=12
            8:00 Am advisory…110 mhp max sustained wind, NW at 12.
            Time of landfall 2 AM Tuesday. WPB or so. IOW…due east of my location!
            Doh!
            Then turning north once ashore and travelling up the center of the state towards Lakeland and Orlando & Kissimmee, heading for GA and Alabammy!
            Good luck planning a safe evac for that contingency.
            Over 24 hours from landfall, it will have moved less than 100 miles, still be a hurricane, and be over populous Central Florida.
            With warm water off both coasts. Being over land with saturated Florida rainy season soil conditions, and a huge number of 90+ ° lakes, and the Gulf Stream and Gulf of Mexico both about 50 miles away…almost like still being over water.
            This path looks like it could do that storm surge thing on Lake Okeechobee like the 1928 hurricane that drowned Belle Glade and such. (that one crossed Puerto Rico and came ashore near WPB)
            https://en.wikipedia.org/wiki/1928_Okeechobee_hurricane
            Those levees will never hold if that happens.
            The whole lake could drain if the levee is washed away!
            Monster flood over the glades, and the Caloosahatchee.
            In 1928, hundreds of square miles were submerged to 20′.
            That would be not good.

  12. Mods, Help!
    My long comment (#comment-2782722) is trapped in moderation.
    Too many URL links I suppose.

    • Your long append does not exactly bring comfort to Brevard County (Cape Canaveral). I’m looking at the Earth site and can’t but notice a strong ridge that might steer the storm Northward sooner and save us all from a lot of grief. Even though I lost over ten pounds of weight getting ready and putting up my hurricane panels with 105 deg heat indes and starting the generator for the first time since Irma I don’t feel that I need to be rewarded for my efforts by having the storm actually hit with the Easter eyewall running over my pool area.

      • I think one thing we know for sure at this point is, “all” are not going to be spared.
        A lot of people are going to get walloped, even if the storm follows the majority of current projections and starts to turn.
        But those projections have been showing a gradual northward trajectory, which is not in evidence with the actual storm.
        At what point will it become a maker of it’s own steering?
        It is now projected to take so long to go anywhere, that new factors could come into play and the models change again.
        At this point I think anything is possible.

        New topic…we see right now why this week is historically the peak of the season…as very quickly every area of cloudiness is showing signs of spinning up to a tropical system.
        We may have four named storms on the map very soon.
        Dorian still moving due west at 7. Not even wobbling from what I can see.

  13. Reminds me of of the very old one-liner that goes,

    “No matter what happens, it is the man’s fault”

  14. gas lines today in florida = INSANITY and the result of the LYING HYPE of the media, where is the storm right now and where is it moving? radar shows not organized and movement slightly to the NNE

    • Yesterday morning, tropical storm to hit the east coast (per my local (Tampa Bay) weather report). By noon it was up to a cat 1, by 6 p.m. it was now forecast to be cat 2, this morning – cat 3, this afternoon cat 4 but if it comes over my area 2 miles from the gulf it’ll be a cat 1 or less. And of course everyone that is easily panicked is out hitting the stores.

      Any wonder why people put little credibility in their predictions of temperatures and sea levels 10 to 100 years from now?

      • Are you old enough or have you been in Florida long enough to remember Andrew in 1992? It was cruising along as a tropical storm then a weak hurricane then it weakened further until it hit the warm waters near the Bahamas. It strengthened very rapidly into a Cat 5 and hit Florida with those winds. Since then they have erred on the side of caution by forecasting the higher category that may be possible to make sure no one is caught off guard again.
        Those that have been here a long time understand these forecasts and as long as we are prepared for the worse we take it all with just part of living in Florida.

        • Hurricane Andrew’s Rapid Intensification (RI) occurred 8/22 to 8/23 in 1992.
          At 22/1800 GMT Andrew’s central pressure was 969 mb; 24 hours later 23/1800 GMT it was 922 mb (-47 mb in 24 hrs), and had sustained winds est at 175 mph, a very strong Cat 5.

          Now look at this graphic of “Historical solar and geomagnetic data charts – 1992”
          The blue lines are the Ap index. Go to August’s panel.
          https://www.solen.info/solar/history/hist1992.html

          The 4th panel down shows the August time frame of interest.
          Ap spiked to 73 on Aug 22-23, exactly when Andrew experienced its only RI episode,

          (The ENSO 3.4 index value was around +0.1 at that time.)

          Just sayin’….

        • i was in juco freshman year in panama city when Camille came ashore, familiar with hurricanes.

    • Bill,
      You are looking at the wrong storm. There is a disturbance off the east coast left over from an old tropical low that never developed. That is what you are describing.

      • i am looking at the storm that missed PR yesterday and is now NW of there, but i was using radar and it isnt any good where the storm is now, the satellite image is far better and i am now using it

          • TY for that link it indeed shows portions north movement, and the storm is now far more north of PR than west of it……

        • Go to where it starts: https://www.sfwmd.gov/ It covers Fl radar and satellite and in this case you can notice a purple line on the right is where the projected path is now. Along with the source of the spagetti model readouts, etc. Invaluable if you live in the area.

        • I looked at Earth and a bunch of other website, and was rewarded with no consequence superior fo finding out this morning that the computed track had moved a whole bunch East. I can now visit the chilled beverage container that I had rewarded myself with yesterday. It is wonderful in Central FL this time of year, and this event is a major event to upsetting Margaritaville.

    • Wait until after midnight or early in the morning.
      Ahead of Irma stores and gas stations and Home Depots were sold out, but these places are even now getting deliveries and diverting trucks for more frequent deliveries.
      I have concluded that most people much drive around with mostly empty tanks, and if everyone tries to fill up, gas stations run out of gas rapidly.
      Plus people have no patience anymore.
      Same thing with bread and water and lumber: If a lot of people decide they need some all at the same time, shelves will quickly be emptied.
      Storm is not even projected to be at the East Coast until Monday afternoon now, if it in facts stays in the center of the cone.

      • Another thing…most people are not early birds, and most deliveries come at night.
        I guarantee tomorrow morning you can buy whatever you want to little or no line.

  15. Ignorance abounds..I’ve heard several people say these hurricanes are more frequent and stronger due to the warmer waters that are a result of climate change..when I ask for sources/evidence they say it’s scientifically proven…my daughter came home from school the other day and told me they were talking about social issues..one of the other kids in her class asked if hurricanes were a social issue because of climate change..fortunately, the teacher said no. God save us..

    • Trained researchers who have spent a lifetime doing nothing else cannot say when and where or how many hurricanes will form or hit.
      People who babysit* small children as the Wise Ones of the atmosphere?
      LMAO!

      *To all of the thin skinned primary school teachers who are angered by this remark: Boo hoo. Stop pretending you know enough to have the atmosphere all figured out.

  16. If Dorian follows the current track, there’s a good chance it will run right over me next week.

    That means I have a lot of hurricane prep to do – the ice cream in my freezer needs to be “removed.”

  17. I am in Florida didn’t see anything that mildly looks like a gas line, although I did fill up because my tank was 1/8 full.

  18. “Why would major hurricane activity vary so much? No one knows.”

    Hurricanes are simply Air pressure relief valves. Sadly not adjustable.

  19. Look at these Modulz!

    https://pbs.twimg.com/media/EDLw15NX4AAPonl?format=png&name=small

    all of them are wrong.

    when it is all over some may get the track closer than others. Some may get the track right, but the rainfall
    wrong. Some may get the track wrong and the windspeed correct.

    How can people run to the store and empty out shelves based on these models that are all wrong
    and wrong in different ways!

    These models are all falsified! how can people still use them ?

    Note, dont tell me I have to build a better a better model. Its enough for me to note 1 mistake and
    the model is toast and should not be used.

    • Its enough for me to note 1 mistake and
      the model is toast and should not be used.

      Really??? Oi vey dood did you need a match for this Strawman or did you want that I use mine own?

      you’re slippin’ faster now

    • I vote we go back to looking at a map and taking a WAG.
      Or, alternatively, people who are not prepared for risk do not live where there is any…wherever that is.
      Let me know when you isolate the risk free locations.
      Steven…I did not know it was you all along!
      Please try to get them models right for once, eh?

      The fact is, it has not happened yet, and no one knows to what degree it is possible to always know what will happen days in advance.
      Program models with what happened for the last five years under a given set of conditions, and they will be wrong if the factor they underweighted or ignored is now the one which has a strong effect.

  20. Official forecast now calls for 140 mph winds as dorian moves over the Gulf Stream, most likely point of landfall south of Lake Okechobee nearer to WPB, and a trun north through the peninsula after coming ashore.
    Worst case?
    It can always be worse.
    Bad?
    If it goes where they now say the highest chance is (no one knows…these are probabilities, not Oracle chiseled in stone knowledge) it will for many be bad enough.
    Perhaps the worst storm in our lifetime.
    Did someone think all the really bad storms could only be in the past?
    No one knows how bad it will be, but there are some bad scenarios coming into play as possibilities.

  21. Friday morning 8:00 am EST. Dorian peak sustained wind speeds currently @ 10m are 57 mph. (NOAA)

    That is barely a tropical storm. The press is reporting Cat 2 with sustained winds at 124 mph.

    Those wind speeds are not being seen at any altitude currently (peak gusts are only at 87mph). What’s going on?

    • Where are you getting that info?
      Keep in mid that even for powerful hurricanes, the strongest winds are in a small core around the eye, and sometimes only in one part of the eye wall.
      If there are no buoys near there, how can a measurement be made.
      I have no doubt that exaggerations are now routine, but that does not mean that strong hurricanes do not happen, or that an area of powerful winds does not exist.
      One reason it is dangerous for the people disseminating data to exaggerate storm intensity, is that when a bad one does hit, people will think they can ride it out. If Michael was a cat 5, well, we see that some houses right on the beach were undamaged.
      The whole situation is very aggravating.
      It means we do not know what is coming and cannot trust the people doing the reporting.
      Adding BS to the uncertainty.
      Anywho…central pressure as of 8AM is 972 millibars. This corresponds to Saffir-Simpson Cat 2 96-110 mph, 965-978 mb.

      http://4.bp.blogspot.com/-J2cOLewnr6A/TslIDFySuqI/AAAAAAAAAGI/xiU2rlhAe38/s1600/saffir-simpson_scale.jpg
      So the official report of 110 mph sustained could be correct and inferred from the barometric pressure.

      • If it is not measured it is bull crap. Show me a wind speed reading taken near ground level or STFU.

        • If they are flying into the storm, then they have dropsondes in the eyewall which measure winds all the way to the surface. Since they have a limited number of dropsondes to use, they have to sort of guess where the highest winds might be, based upon where the strongest convection is and SFMR (microwave radiometer) measurements of where there is the most surface foam being generated.

        • Right back at ya, pal.
          So nice to hear from a psychopathic troll.

          I am guessing you are not employed in the field of public safety.

          • We rely on the computer too much, because it is easy, even though it is usually always wrong. The width of the forecast cone shows you the limitations. You can’t model something if you don’t understand the system. Dropsondes are the way, not computer generated crap from high level winds. The hype in this forcast has almost the entire state freaking out.

      • “The CIMSS Satellite Consensus (SATCON) product blends tropical cyclone intensity estimates derived from multiple objective algorithms to produce an ensemble estimate of intensity for current tropical cyclones worldwide. The algorithm uses individual ADT, CIMSS AMSU, CIMSS SSMIS, CIMSS and CIRA ATMS intensity estimates utilizing a statistically-derived weighting scheme which maximizes/minimizes the strength/weaknesses of each technique to produce a consensus estimate of the current tropical cyclone intensity. The goal of this work is to produce an estimate of intensity that is superior to the individual components. Statistical verification of the method has shown it to be comparable in skill to the Dvorak Technique used by tropical cyclone warnings agencies. In some situations the algorithm can outfperform the Dvorak Technique.

        A statistical analysis of each of the member algorithms was used to determine the individual member performance in a variety of TC structures. Each algorithm has strengths and weaknesses that are a function of the algorithm limitations, scanning geometry, instrument resolution or a combination of these factors. For example the ADT algorithm assigns a scene type to each IR image of a TC. ADT performance is strongly dependent on scene type with the best performance for scenes when a clear eye is present and decreased algorithm performance for other scenes. Because of this dependence the ADT is weighted according to scene type.

        The microwave sounder algorithms are sensitive to TC core size as compared to the instrument resolution. Eye size information is provided by the CIMSS ARCHER algorithm, the ADT or the warning agency working Best Track in that order of availability. If the TC eye size is small than the sounder FOV resolution a correction is applied. In addition because of the relatively coarse instrument resolution it is possible that the true TC center may not be co-located with the instrument Field of View (FOV) used for the estimate. This source of under-sampling is addressed in AMSU using information from the AMSU-B moisture sounder. Microwave sounder performance is best when the TC eye is sufficiently large compared to the FOV resolution therefore the sounders are weighted according to whether or not the TC inner core is resolved. In the case of the CIRA ATMS algorithm only estimates where the TC eye size is larger than 40 km are used.

        Because the ADT estimates are available for every infrared satellite image it is desireable to have matching microwave sounder estimates. To accomplish this the polar orbiting satellite estimates which are available only at irregular times are interpolated to hourly estimates. These interpolated estimates are then combined with the ADT estimates using the weighting approach. CIMSS ATMS estimates are treated as an SSMIS member because the two instruments have similar resolution/performance and this improves the fidelity of the interpolated values. SSMIS and ATMS sounder estimate weights are adjusted based on the age of the estimate using an exponential decay rate. Thus estimates older than 3 hours have decreasing weight which approaches zero once the estimate is older than 6 hours. This is done because there are currently only two sounders available at this resolution.

        In order to account for storm structure differences that relate to TC intensity a Pressure-Wind (P-W) relationship-based SATCON estimate is produced. The P-W SATCON Vmax estimate uses the pressure anomaly derived from the SATCON estimate of MSLP and an estimate of the environmental pressure obtained from the warning agency (NHC or JTWC). This estimate is then corrected to account for bias as a function of latitude, storm size (distance to outer closed isobar also obtained from the warning agency), TC eye size (from ARCHER or ADT only), and intensity. The intensity bias correciton primarily adjusts the SATCON Vmax for a known slight too weak bias for the strongest storms. The final SATCON Vmax estimate is 75% of the SATCON Vmax members estimate and 25% of the SATCON P-W estimate.

        The goal of SATCON is to produce an estimate of TC intensity that is superior to both the individual members and a simple average of the members. The tables below show the statistical performance of the algorithms for the 2006-2015 period. Validation consists of warning agency best track estimates of Vmax and MSLP during periods when aircraft ground truth was available within three hours of the intensisty estimate.”

        http://tropic.ssec.wisc.edu/misc/satcon/info.html

        • In the last 3 years NOAA always shows all hurricanes 2 cats higher than they really are. For example Dorian is at 90mph right now – category 1. And no land-point in Florida will probably experience even 60mph…
          185mph?? Where? When? Pressure 910? I’ve only seen 955.

  22. I’ve updated my blog post to include Hurricane Michael (2018), which was previously excluded. My apologies. The conclusions don’t change.

  23. I stay in Clermont, Florida. Ckermont is west of Orlando. I work at a Publix Supermarket in the area. Yesterday we ran out of a truck load of water. Publix had a purchase restriction, 4 gallons or two 24 bottle cases. Once again, we ran out of water YESTERDAY! Talk about people panicking! Today, (day off work) I was doing errands in 2 counties using buses. Late afternoon/early evening, the majority of gas stations we passed were closed. OUT OF GAS! Talk about people panicking!

    • Correction: gas stations weren’t closed. The gas pumps were closed. Plastic bags over the handles. Clermont, not Ckermont. (second usage in my post).

    • …not to mention that Publix is HQ’d in nearby Lakeland, right? It isn’t like Clermont is out on the fringe.

    • Are you willing to bet your life, or the lives of many thousands, possibly millions, or people on that thought?
      Do we suddenly have a consensus of modelling stalwarts here on WUWT?
      If those spaghetti plots were not showing that storm curving, when would you think just looking at the strength of it and the path?
      Dorian is already ignoring the models and the forecast path.
      18-23 foot surge in Bahamas. Huge waves on top of that.
      It was moving west at 280° most of last night, now west at 275°. Opposite of what it is supposed to be doing.
      Staying in front of that storm is like playing a game of chicken but the other driver is a computer.
      Cone of uncertainty does not include the path actually taken 1/3 of the time.
      Right now edge of that cone is Boca Raton and Coral Springs, curving north to the shore of Lake O.
      But that includes a path that is right now moving north by northwest.
      4 PM special advisory…almost exactly due west at 7 mph.

      • “…Are you willing to bet your life, or the lives of many thousands, possibly millions, or people on that thought?…”

        Overly dramatic much? He said he didn’t “think” the eye would make landfall in FL. There are watches, warnings, and mandatory evacuations. JPP isn’t cancelling those or telling people to stay at home and relax because there’s no way in hell that there will be a landfall in FL (not to mention that some evacuations are necessary even if it doesn’t make landfall…it will likely be close enough and strong enough to cause significant damage to the east coast with wind, rain, and storm surge).

        “…Do we suddenly have a consensus of modelling stalwarts here on WUWT?
        If those spaghetti plots were not showing that storm curving, when would you think just looking at the strength of it and the path?…”

        The NHC doesn’t just rely on models. I’ll listen to their expertise over, “OMG what if it just kept going straight west and never turned!!!!”

        “…Cone of uncertainty does not include the path actually taken 1/3 of the time…”

        That’s across the entire 5 days, and it is usually fast-moving storms which leave the cone. Dorian is currently a slug. Dorian hasn’t hit the meteorological features that will send it north. Stop wetting your pants.

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