Guest Post by Willis Eschenbach
When is a hurricane not a hurricane? Well, when it doesn’t blow 64 knots (33 m/sec, 74 mph), because then it’s only a tropical storm. Inspired by a post over at the Cliff Mass Weather Blog, I’ve been trying to find a single report of sustained hurricane force winds anywhere along Irene’s path at or near landfall … no joy. I knew exaggeration was the order of the day for some folks in the climate debate, but I hadn’t realized that the illness had infected the Weather Service itself.
Figure 1. The path of Tropical Storm Irene over the mainland of the US. Symbols with a yellow center to the black storm symbol indicate a (claimed) hurricane. SOURCE ibiseye
We were fortunate in that we have very good records of the wind speed when Irene made landfall. It went almost directly over the wind recording station at Cape Lookout, at the bottom of Figure 2.
Figure 2. A closeup of Irene’s landfall. There are four wind recording stations in the area, at Beaufort (below the “70” marker at lower left), at Cape Lookout (bottom left) and at Cape Hatteras (upper right). The Onslow Buoy is located offshore, southwest of Cape Lookout.
The wind record at Cape Lookout is quite interesting, as the eye of the hurricane passed right over the anemometer there. Figure 3 shows the wind dropping as the eye went over, coincident with the deep plunge of the barometric pressure to 950 hPa.
Figure 3. TS Irene wind (light blue) and barometric pressure (violet) at Cape Lookout before, during, and after landfall. Green line at the top shows the minimum wind speed for a storm to be classified as a hurricane (64 knots).
Figure 3 shows the classic pattern of a hurricane passing directly overhead. The “eye” of the hurricane has almost no wind, and is at the center of the low pressure area. You can also see the “calm before the storm. But what you can’t see is any trace of hurricane force winds.
Not finding hurricane force winds at the eye, I looked at the other nearby stations as well. The weather station at Cape Hatteras is in the “dangerous semicircle”, the right hand side of the storm track (Fig. 2) where the speed of the storm is added to the speed of the winds circulating around the eye. Beaufort, on the other hand, is in the safer half of the storm, where the speed of the storm is subtracted from the circulating speed of the winds. The Onslow Buoy is also in the safer semicircle, on the left of the storm track in Figure 2. Figure 4 shows those records.
Figure 4. Winds at TS Irene landfall for Cape Lookout, Beaufort, Onslow Offshore Buoy, and Cape Hatteras.
As you can see, although Irene definitely qualifies as a solid tropical storm (winds greater than 35 knots), it does not reach or even really approach the 64-knot threshold for hurricanes. Other than at the eye itself, the winds did not exceed 50 knots, much less reach 64 knots.
After crossing over the land near Cape Hatteras, Irene headed back out to sea again. I thought perhaps it might have picked up steam when it went out over the ocean again. It made a second landfall in Atlantic City and went along the coast to New York.
Figure 5. Second landfall for Irene.The nearest stations to Irene’s track are Costeau (near Mystic Island above Atlantic City), NY Harbor Buoy (outside the mouth of the harbor, in the dangerous semicircle), Sandy Hook (hook shaped peninsula just above Long Branch and central hurricane symbol) and Kings Point (near New Rochelle above New York City). Note that the storm is claimed to be a hurricane until it gets well into New York State.
It appears from an examination of the station data shown below in Figure 6 that it did not pick up strength over the water. By the time Irene reached land a second time, it barely qualified as a tropical storm, much less a hurricane.
Figure 6. Wind speed from Tropical Storm Irene as it made the second landfall.
So, despite looking at Irene before, during, and after both landfalls, there is no hint of a hurricane anywhere. By the time it got to New York the eye of the storm had dissipated, what was left were huge bands of rain clouds.
Is there a moral in this story? Well, I can understand people taking extra precautions, better safe than sorry is a good rule. And I certainly imagine that when the Weather Service re-examines the records, the error will be corrected.
But that doesn’t help in making the decisions. As soon as Irene hit land, it should have been downgraded immediately to a tropical storm. That’s what it was, not a hurricane making landfall but a tropical storm. As far as I can tell, we still haven’t had a hurricane make landfall during Obama’s presidency, a historical oddity.
Individuals and city mayors and the people in charge of the emergency response can call for any level of reaction to storm threats. They may decide an exaggerated response is appropriate.
But they need accurate information to do that, not exaggerated claims. They need the actual facts, the best estimates with no exaggeration on either the high or low side.
In this case, it appears that people got so wrapped up in the question of the winds, and the fear of the winds, that they overlooked what actually made Irene unusual. This was not the wind speed, but the size of the storm. Combined with Irene’s generally slow movement over the ground, Irene’s huge dimensions meant that any given area would get rained on for a really, really long time.
And in turn that meant that the cities and towns along the coast, the ones receiving all of the attention from the fear of high winds and attendant storm surges, weren’t the towns in danger. Unlike the coastal cities, the vast expanses inland were not able to have the rainwater just flow back into the ocean. Inland, the water piled up and overflowed the banks.
And so, because of the overestimation of the wind speeds, our attention was diverted from the real threat. Because of the claimed hurricane-force winds, a storm surge up to eight feet was predicted in New York Harbor. But in the event, the storm surge was barely three feet, a non-event … and meanwhile, New England was getting badly flooded.
So the moral to me is, honesty is the best policy for a National Weather Service. Don’t exaggerate the possible effects to be on the “safe side”, don’t minimize the possible effects. Just give us the best information you have, and let us make up our own minds. As Sergeant Friday used to say … “Just the facts, ma’am” …
w.
NOTE: All wind data is from the NOAA National Buoy Data Center http://www.ndbc.noaa.gov/.
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Willis,
The 32.6m/s at the Duck Pier was not a gust, it was a sustained 1-minute wind speed (see the links I posted above). The gust reported at the same time was 36.2m/s (max 5-sec gust during the previous 10 minute interval was 37.6 m/s).
Granted 19.4m is not the same as 10m and probably (maybe) should be adjusted downward a teense. But was are talking about a wind that was largely coming in off the ocean measured at the end of a pier, so the attenutation from 19.4 m down to 10m is probably not much.
Like is said previously, with an observed wind so close (within ~1 m/s) to hurricane strength, it seems a stretch to assume that the Duck Pier instrument was at the exact right place to measure the highest wind.
-Chip
The Beaufort wind scale was developed to help mariners estimate wind speed. Thus we have Gale force 8, storm force 10 and hurricane force 12.
Mariners are known to be on the surface as are observers on land. Thus the scales refer to surface winds.
Jet streams speed along at high level. We dont call them hurricanes.
The descriptions follow the observed surface wind speeds. Not the other way round and are purely a general advice based on experience what will happen when those wind speeds are observed. They dont take into account waterlogged soils or trees in full leave or old trees.
Any attempts to change the observing rules to higher altitudes or whatever are purely blatant attempts to move the goalposts to get desired results, not comparable observed results.
In this case it is a desperate need to get a recorded “hurricane” landfall after a total lack of them contrary to their cherished theory.
In simple terms, without any hype and based upon long standing observer rules and definitions this was not a hurricane upon landfall.
QED
Willis Eschenbach says: September 1, 2011 at 2:08 pm …. Miss the point.
Willis, I think you miss the point. Go ahead and get Irene downgraded to a TS. That won’t change the damage and death tolls.
My point is that I want people to RESPECT strong Tropical Storms because they cause as much or more overall damage than tightly knit hurricanes. The real sin in Irene was the opinion. “Oh, it was only a TS, what was the fuss?”. This was an opinion that was flying around the TV on Sunday at 11 am!! OMG! Manhatten didn’t flood! You must have over-reacted to the danger!!”
Do the Decision Tree. Put yourself in the place of the Mayors of NYC and Ocean City and Head of the MTAs. “Should I have hotels full of tourists at 6am? Should I have rolling stock and passengers in subways at 7:30am on Sunday morning? Should we have a normal business day two hours after landfall?” Are you out of your mind????
For the record, I want to make clear that I do NOT advocate evacuating cities in the event of even Major Hurricanes. We must prepare and harden our cities to withstand a Major. If you are in danger of flood surge, get out or get up. Otherwise, leave the roads for those with no other option. Each of us must be prepared for living 14+ days without power. (It was 8 days for me in IKE). But, if there is a flood possibility from even a weakened TS, don’t do something stupid like carry on as normal. And if it turns out to be 52 mph (and 14″ of rain) instead of 67 mph and 8″ of rain, count your blessings instead of insurance claims.
Willis,
Outstanding analysis of data,
Your conclusions confirm the observations reported/observed on the ground in NJ and indicate that the experts either are not as smart as they would like us to believe, or they were not honest about the nature of Irene. Your findings should be studied more thoroughly to understand the data/findings.
Some points to reinforce your observations.
I own a house in Forked River NJ which is about 74 miles of Cape May which is the lower tip of NJ
The Landfall was about 30 miles South of Forked River
Your plot shows that the eye of Irene passed a few miles west of Forked River
Weather underground was predicting about 49 mph winds for Forked River
We evacuated 100 miles to the North about 40 miles west of NYC but our Forked River neighbors reported very mild winds
No evidence of any significant winds at my Forked River home, including no impact to my boat which was in the lagoon about 1/8 mile west from the Barnegat Bay that I thought would sink based on the forecast winds/rain. No loss of electricity. I don’t see any treees down or leaves around the house or anywhere in town.
Storm surge was significantly less than preddicted
No evidence of surge problems in Wildwood which was along the path of Irene.
My son went to Long Beach Island NJ the barrier island east of the eye, no evidence of damage what so ever, some Beach erosion but nothing like a typical NE storm.
On the other hand at my location in Northern NJ (Denville) 90 Mi North circa 50 miles west of Irene path. I lost power for 45 hrs (starting at 4:30 Sunday PM after the eye was well North). Numerous power outages spreading all around north western NJ into Penna. Lots of trees down in area broken off in the trunks (not rooted up), leaves and small branches all over my mostly wooded lot, massive flooding in Denville along the Rockaway river, more than I have seen in over 40 years, flooding in areas never flooded before. http://www.youtube.com/watch?v=Pyj7mTKoEVU
Don’t get me wrong, evacuation of the NJ coast IMHO was prudent, but someone needs to explain how the winds and damage were non existant along the “actual” path of the storm while serious wind and flooding occurd well west of the storm. HOW CAN THIS BE CALLED A HURRICANE IN NJ?
Willis, your analysis exposes a serious flaw in our understanding of Hurricanes or possible hiding actual data during the storm. Understanding this is essential if the forecasts are to remain credible.
It is not trivial.
So what Steven Goddard reported at his blog about Irenes wind speed was correct.
Robert Smith says:
September 1, 2011 at 12:27 pm
I’m depressed. Here in Orkney, North Scotland, we had sustained wind of 50kts with gusts over 70 last sunday and nobody cared. 🙁
L-O-L! Nice one!
As I read this thread, and other posts, I see that I was correct in saying that we did not have a hurricane or that all wind sensors were broken all over the eastern US.
But now what? Like the movie Wag the Dog, this has been on TV as a hurricane and will remain so. NOAA will never correct, and wikipedia will call it a hurricane.
The only thing we know for sure is that NOAA will never again be an honest broker of data; if it ever was. The destruction of honest science continues unabated.
To me, this is actually the important point of Willis’ post:
“In this case, it appears that people got so wrapped up in the question of the winds, and the fear of the winds, that they overlooked what actually made Irene unusual. This was not the wind speed, but the size of the storm. Combined with Irene’s generally slow movement over the ground, Irene’s huge dimensions meant that any given area would get rained on for a really, really long time.”
(My bold)
Here in the UK, we may not experience hurricanes so much – but we do have experience with rain, especially extended rain, and concomitant flooding on grand scales and on smaller, local ones which can be even more devastating:
* Boscastle 2004 – http://en.wikipedia.org/wiki/Boscastle_flood_of_2004
* Cockermouth 2009 – http://www.visitcumbria.com/cockermouth-floods.htm
* Huge floods in the UK in 2007 – http://en.wikipedia.org/wiki/2007_United_Kingdom_floods
These are events which made national news, but there are of course local events which can be similarly devastating, albeit to a much smaller number of properties and people.
So, it doesn’t pay to get stuck solely on wind speeds, or definitions of hurricanes, devastating as they undoubtedly are. ‘Gentle’ rain, falling on saturated grounds, with nowhere to go, also has devastating effects. Clearing up after storm damage is one thing – clearing up after a flood is far far worse, and takes much longer.
Willis is right:
“And so, because of the overestimation of the wind speeds, our attention was diverted from the real threat. Because of the claimed hurricane-force winds, a storm surge up to eight feet was predicted in New York Harbor. But in the event, the storm surge was barely three feet, a non-event … and meanwhile, New England was getting badly flooded.”
(My bold)
You guys scare me sometimes. There isn’t always a great conspiracy at every corner. Here’s a newflash. We landed on the moon. JFK was shot by a single gunman. Yes, a plane crashed into the pentagon on 9/11. And the NWS isn’t trying to trick you guys. Really! Not everyone is out to get you, so quit being so dramatic.
The truth is that hurricane forecasting is not perfect. They may have in fact gotten the intensity wrong at landfall, but, don’t worry. NOAA will analyze all available data and if it was actually a tropical storm at landfall then it will be so. Even the wikipedia page will say so. Trust me on this.
The most famous example of course is Andrew. the NWS had it at a cat 4 upon landfall but clearly it was not.
eyesonu says:
September 1, 2011 at 11:18 am
In my earlier post I meant to write ‘west’ of the storm instead of ‘east’.
“Through my observations of estimated rain storm totals derived from radar, I could see that 30-50 miles west of the center of the so-called hurricane, they were in the 10-12″ rain estimates. TV was still concentrating on wind, but that was not the real issue with this storm”.
thelastdemocrat says:
September 1, 2011 at 6:06 pm
But now that all of Storm Irene’s energy can be declared a ‘hurricane,’ its cyclonic activity can be added to the cumulative sum for this season. This is necessary, since this year otherwise would be another disappintment just like last year.
—————————-
Keith responds:
September 1, 2011 at 6:36 pm
Well off the mark here I’m afraid. It’ll contribute to the ACE index by virtue of being a tropical cyclone, regardless of intensity. You seem to have overlooked that it was a hurricane for a good five days, no matter what its intensity at NC landfall may have been.
—————————
@ur momisugly Keith, my response,
I wonder if someone took a boat offshore to verify the wind speeds that were reported in those 4 days? If the NHC was willing to report ‘ xxxxxxx ‘ among countless witnesses and documentation onshore, who could possibly trust without verifying their reports offshore?
I now wonder about the ‘Nanny State’ and how much the NHC may have gotten involved. The NHC should be moved to the ‘trust but verify’ catagory. Perhaps if a scale to the ‘trust but verify’ were incorperated, they would be rated a ‘catagory 4’ with regards to producing wind (pun intended),
I think the idea that hurricanes are, by their title, more devastating than storms is wrong headed thinking. The post is right on the money. Let’s hope the NWS gets this. Lives could be saved by readjusting their thinking from “titles” to damage potential for any system on its way to your community.
Chip Knappenberger says:
September 1, 2011 at 8:57 pm
Willis,
The 32.6m/s at the Duck Pier was not a gust, it was a sustained 1-minute wind speed (see the links I posted above). The gust reported at the same time was 36.2m/s (max 5-sec gust during the previous 10 minute interval was 37.6 m/s).
Granted 19.4m is not the same as 10m and probably (maybe) should be adjusted downward a teense. But was are talking about a wind that was largely coming in off the ocean measured at the end of a pier, so the attenuation from 19.4 m down to 10m is probably not much.
Like is said previously, with an observed wind so close (within ~1 m/s) to hurricane strength, it seems a stretch to assume that the Duck Pier instrument was at the exact right place to measure the highest wind.
-Chip
=======================
Chip, my response.
Thank you for your participation in this discussion. I checked out the link to the data site you posted in an earlier comment (military related data?). If I remember correctly, readings were recorded every 10 minutes and there was an increase and decrease in wind speed over maybe an hour or so with the crest as you noted above and the other readings were a fair amount less. Could this also be viewed as a good puff of wind lasting a short period? This is common in some thunderstorms where I live and I certainly never considered calling it a hurricane.
As far as your strong suggestion that since it was almost a hurricane for a few minutes at one recorded location and thus should be considered one, is this pushing a stretch of the imagination for a desired outcome? Is this splitting hairs to find some way ‘to make it so’?
I really believe the NHC cooked the books and has been possibly since 2005-the last really active season. Why? To prove a theory that is with time being proven to be a farce. There is a lot of money tied up in AGAW. There has been no landfall of a hurricane in the US in 3 yrs. There has been a marked decrease in the number of tropical cyclones in the world since 2005. These storms thrive on heat-turn the heat down-less storms-less intense storms-more hybrid storms that are not 100 percent tropical. The westerlies assume a more southerly position which tends to shear the storms more quickly and the resulting troughs absorb these storms that do form and turn them into hybrids. I do believe the globe did warm from the mid 70s to about 2000-the trend began to reverse at 2000, but the oceans are since 2005 only beginning to catch up-the reduction in strong tropical systems is a symptom of this. The arctic has yet to catch up-it is the last stronghold and will take the longest to catch up with the reversal, so there may be a few years yet to go before it shows up there.
Joseph says:
September 2, 2011 at 2:55 am
“The only thing we know for sure is that NOAA will never again be an honest broker of data; if it ever was. The destruction of honest science continues unabated.”
Yes, that is the lesson. After this clear demonstration of NOAA’s unwillingness to use its own data on the ground, the essential wind speed data, only a fool would not be sceptical of everything that comes from government weather or climate agencies.
Well that’s a home run right there Ryan. Frankly you just singlehandedly destroyed any attempt that the climate bureaucracy could advance along the lines of: better to keep calling it a hurricane so people will prepare.
The NWS, NOAA and the press could easily have used the more accurate very strong tropical storm with near hurricane force winds and satisfied everybody while keeping themselves scientifically precise.
This whole thing smells bad now, real bad. It has political science written all over it in my opinion. If I am wrong then at the very least we have junk science written all over it because of the discarding of a precise scientific definition. BTW, nobody is saying to throw NWS under the bus (I don’t believe they have the equivalent of Mark Serreze stinking up the place), but someone there did greenlight the term ‘hurricane’. This would make for a good case study there and at NOAA to find out the names of the actual people involved. If there are hack political scientists employed they must be rooted out, exposed, shamed and fired.
On the thread about Hansen getting arrested there was a brilliant comment by Tom_R: “If someone is willing to break the law in order to ‘save the planet’, why wouldn’t he also be willing to fudge the data?“
To paraphrase: “If someone is willing to break the scientific definitions in order to ‘save the people’, why wouldn’t he also be willing to fudge the data?“
Willis, you did us all a service here by pointing out that what was called a hurricane was, for some of that time, not a hurricane.
That observation is important, in that it appears to point to a pattern of exaggeration, and plays well on this blog. But the folks in NJ and VT that have been flooded out of their homes aren’t going to care about the distinction, it seems to me. Even tropical storms can cause a great deal of damage because of massive rains.
When folks on the other side greatly exaggerate something that is palpably incorrect, and isn’t associated with actual harm, but rather just trying to scare people to death — starting with the hockey stick and glaciergate and climategate and all the rest — ridicule of obvious climate huckerism is crucial.
But we don’t want to ridicule the exaggeration here, it seems to me, because even if the ridicule is correct, it makes us look like we don’t understand or care about the actual devastation that occurred. Like we care only about a legalistic point, but not the damage that people suffered. Let’s give this particular exaggeration a rest.
Willis: I’m not sure the ground-based wind speed readings are accurate or telling the whole story. We’ve all seen pictures of the downed trees and trees that have been topped. I don’t need the photos; I can look out the window. Yup, there’s one, and another… But there’s another phenomenon that isn’t being reported. The leaves that remain on the 100+ hickory, maple, oak and birch trees on my property have been shredded at heights above 20 feet. There’s hardly anything left of them.
The following analogy may be useful:
A hurricane is like a snowflake. A scientist is able to say with a degree of certainty that a small drop of water will form a snowflake, but cannot tell you what the snowflake will look like, because no two snowflakes are alike.
The forecaster Joe Bastardi blows me away, with his ability to see things in the long range. He saw Irene coming weeks ahead, and a couple of weeks ago said there would likely be a storm in the gulf as one approached and curved up the eastern seaboard. There is no way I could have predicted that, but when I look at today’s map I see the two storms.
This is like saying “The snowflake will form.”
Where Mr. Bastardi fails, (if you can call it a failure to be so right,) is in the last-minute tweaks, concerning the individuality of the storm.
This is like saying , “The snowflake will look exactly like this.”
Over the years I have never seen two hurricanes behave exactly alike, and some are amazing in the way they do unexpected things. (I think that is why, back when male chauvenism was allowed, they were named after women: They cannot be predicted; and seem illogical to people who demand all be mathamatical and pleasing to accountants.)
Consider Irene: Have you ever seen a storm with 950 mb pressure NOT have hurricane winds?
Give the forecasters a break, regarding the winds. I do think they could have focused more on inland flooding threats, however.
SABR Matt says:
September 1, 2011 at 7:43 pm
That doesn’t follow logically. Irene was a very weak hurricane, rapidly becoming a tropical storm, when it hit land. There have been a number of much stronger actual hurricanes that have hit the outer banks, with much greater winds. Do some reading of history.
Yes, we ESTIMATED the wind (to use your term) using the Beaufort Scale. We don’t do that much any more, that’s why it’s called the “old days”. These days we use instruments called “anemometers” to measure the wind speed.
In any case, I doubt very greatly if you can tell me the Beaufort Scale indications that differentiate a strong gale from a hurricane without looking them up … so you’re just giving us your opinion, it’s not really based on the Beaufort Scale or anything but your ideas.
A sustained wind is a wind that lasts a couple of minutes, as opposed to a gust, which basically goes up and comes down again by tens of knots in a few seconds. I gave the official definitions upthread.
You write that Irene had “surface winds well over that 74 mph” … and also that those same surface winds “had trouble making it all the way down to the surface”. I fear that’s totally unclear. It’s also immaterial, as you are talking about the time long before landfall.
I liked the part about “… there was a hurricane here. Period.”
I’m sorry, but we no longer find it sufficient to squint into the wind and say “yep, that-thar’s a sure ‘nough hurricane. Period.”
These days, we use anemometers, so we can measure the wind speed to see if it is strong enough to be called a hurricane.
You state strongly that you live on Long Island, as if where you live made the slightest difference to what the wind speeds were. I’ve been through a real, live, no-nonsense hurricane, seventy-knot winds measured on land. Hurricanes have sustained winds way, way above anything for which we have evidence on Long Island.
Well, if it’s beyond you, you might think of it like a speed limit. You know, if the speed limit is 65 mph and you’re going 65, well, that’s not speeding … but by god … 3 more mph and a trooper can legally pull you over and write you a ticket. That puts you into a different categore we call “speeding”, but the he issue is not what we call it, the issue is the difference in speed.
And as someone pointed out above, that designation of a “hurricane” (sustained winds greater than 64 knots) vs a “tropical storm” (sustained winds greater than 35 knots) might make a difference of thousands of dollars in insurance payments. It can also make a difference in whether you decide to order a costly evacuation with its associated problems.
Finally, the power of the wind goes up roughly by the cube of the wind speed. So a doubling of wind speed gives it around eight times the destructive power. Which is another reason why a few knots make a difference.
Overhyped? You are desperately overhyping Irene as though it were a real hurricane, and at the same time you say you’re tired of reading about how it is overhyped? Irony much? Grab a mirror real quick …
I’m tired of folks who don’t read what I wrote. Go accuse someone else of being heartless, I know my heart too well to listen to your nonsense. I didn’t say anything was hyped at all, either over- or under-hyped. I didn’t use the word in my head post at all.
My question is simple, Matt, and it has nothing to do with overhype.
If it was a hurricane, where are the wind speed records that show it?
I’ve asked that from the start, and no one has come up with a single hurricane wind speed record from any land or near-land station … yourself included.
w.
To emphasize what Willis has been saying to those who are trying to defend Irene as a hurricane by pointing to the damage in Vermont and NH: that damage was done by heavy rains, not anything remotely close to hurricane force winds. In fact, it was the media and the government’s attention being focused on the winds along the coast that made them ignore Vermont and NH, and not prepare the people there for the flooding that has caused so much damage and caused lives.
See, the whole issue with this “hurricane” Irene is one of misdirection. And this misdirection has cost the inland states severely, as no preparations were given to them against the real threat of rains.
Chip Knappenberger says:
September 1, 2011 at 8:57 pm
Thanks, Chip. Several things about that. First, as a general rule of thumb the windspeed goes up by about the 1/7 power of the increase in height. For unstable air on a flat open coast it’s a bit less, about the 0.11 power of the increase in height. For a 19.4 metre measurement height, we need to reduce the speed to about 93% of the measured speed to allow for the difference in height. This give us a speed of 32.6 * 1.94 * 0.93 or about 59 knots, well below the hurricane level. The wind would have to increase by a whole 10% in speed to get to the hurricane level, which might not seem much, but which is about a 30% increase in wind destructiveness and which requires a 30% increase in power to get there … so no, Chip, it was a long ways from a hurricane even at Duck Point. To be a hurricane, it needed 30% more power than it had. Not close at all.
Second, curiously Duck Point is about the exact right place to measure Irene’s highest wind. It is in the dangerous semicircle, and was only about ten miles or so from the path of the eye, with a flat landscape. I can’t think of a much better location for measuring a hurricane’s strength … and it wasn’t a hurricane there.
w.
Stephen Rasey says:
September 1, 2011 at 9:31 pm
Stephen, Manhattan did over-react to the danger, because they’d been told the danger was the wind and particularly its attendant storm surge (predicted to be as high as 8 feet). In the even, the storm surge was less than half of that, and posed no danger. New York wasted millions of dollars due to inaccurate information.
I agree that people should respect tropical storms. I also think that we should have accurate information when either one approaches our coast. We didn’t get that … and you seem to be defending the handing out of inaccurate information.
??
w.
Joe C says:
September 2, 2011 at 4:30 am
The newsflash is that there isn’t always a great conspiracy theorist at every corner. I’m certainly not saying there was a “conspiracy”, that’s you seeing things, likely should check your meds. Most folks here don’t think there’s a conspiracy, just that the strength of the storm was overestimated … and that’s what we’ve been discussing, whether the storm was over-rated.
The only thing worse than people who claim a conspiracy at the drop of a hat are their evil twins, those who see conspiracy theorists in every discussion. Lead, follow, or get out of the way, because your whining about conspiracy theorists is going nowhere. If they pop up, just let them be, and try to actually contribute to the ideas under discussion.
w.
Bob Tisdale says:
September 2, 2011 at 8:24 am
The “ground-based” wind speed is measured 10 metres (30 feet) in the air, up at the height of tree leaves … so I’m not sure what your point about trees and leaves is. Yes, the winds increase with altitude, as you point out, but the scientists knew that and measure at 10 metres height for that reason.
w.