
Update 11:00 PM EDT: Igor still intensifying, now at 130 knots (Cat 4) and now forecast to become a Category 5 within the next 12-hours. See NHC bulletin at the end of this post.
Hurricane Igor has rapidly intensified into a Category 4 storm over the open Central Atlantic. Winds are expected to remain above 115 knots for the next several days which will allow for considerable Accumulated Cyclone Energy production. The North Atlantic basin as a whole will almost assuredly be above the climatological average in terms of ACE for 2010. I keep track of the global tallies on my Florida State University page. Note that the Pacific basin has been historically inactive due to the onset of the strong La Nina. The Northern Hemisphere ACE as a whole is on pace to be the lowest since 1977, and be even lower that the wimpy total of 2007.
The NCEP GFS and ECMWF forecast models both indicate that Igor will be a fish storm (of course fingers crossed for Bermuda escaping the storm):
Figure. GFS maximum wind swath for the next 180-hours (wind speed in knots). Note the presence of TD12 — likely to be Julia.
Figure. ECMWF maximum wind speed for the next 10-days. Note that this model is capable of generating more reasonable wind speeds for tropical cyclones (actual Category 4 and 5 winds) due to the incredible grid point resolution of the forecast model (T1279 = ~16 km globally).
Homework assignment: The name Ivan was used 3-times prior to being retired in 2004. Here is the list maintained at the NHC of named retired and the year the storm occurred. The rules for retirement are defined by the WMO, but a landfall does not necessarily mean that a given storm name will not be used again 6-years later.
Trivia questions to determine: instead, over the past 60-years, regardless of name, say that we retire all names of “hurricanes 64 kts+” that make landfall anywhere, which letter would be the most retired? What’s the next letter that is due to be retired?
=========================
BULLETIN
HURRICANE IGOR ADVISORY NUMBER 20
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
1100 PM AST SUN SEP 12 2010
…IGOR STILL INTENSIFYING…
SUMMARY OF 1100 PM AST…0300 UTC…INFORMATION
———————————————–
LOCATION…17.6N 47.8W
ABOUT 1005 MI…1620 KM E OF THE NORTHERN LEEWARD ISLANDS
MAXIMUM SUSTAINED WINDS…150 MPH…240 KM/HR
PRESENT MOVEMENT…W OR 270 DEGREES AT 13 MPH…20 KM/HR
MINIMUM CENTRAL PRESSURE…935 MB…27.61 INCHES
WATCHES AND WARNINGS
——————–
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.
DISCUSSION AND 48-HOUR OUTLOOK
——————————
AT 1100 PM AST…0300 UTC…THE EYE OF HURRICANE IGOR WAS LOCATED
NEAR LATITUDE 17.6 NORTH…LONGITUDE 47.8 WEST. IGOR IS MOVING
TOWARD THE WEST NEAR 13 MPH…20 KM/HR. A TURN TOWARD THE
WEST-NORTHWEST WITH SOME DECREASE IN FORWARD SPEED IS EXPECTED TO BEGIN LATE MONDAY AND TUESDAY.
MAXIMUM SUSTAINED WINDS HAVE INCREASED TO NEAR 150 MPH…240
KM/HR…WITH HIGHER GUSTS. IGOR IS A CATEGORY FOUR HURRICANE ON
THE SAFFIR-SIMPSON HURRICANE WIND SCALE. SOME FLUCTUATION IN
INTENSITY IS LIKELY DURING THE NEXT 48 HOURS…AND IGOR COULD
BECOME A CATEGORY FIVE HURRICANE ON MONDAY.
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Best site I have seen so far is http://www.myfoxhurricane.com/ from Fox13 out of Tampa.
So is that Ee-gor or Eye-gor??
Ryan N. Maue says:
September 12, 2010 at 3:49 pm
Reply:
I am testing a new hypothesis, I didn’t know how sound it was without testing it, I will see how it turns out at the end of the season as to how much of it was wrong and by further modification with more data.
Nothing ventured nothing gained.
Ryan Maue says:
September 12, 2010 at 5:04 pm
Also, if you Google hurricane igor, WWUT shows up on the first page…This is evidence of Anthony’s hard work and the contributors to his site, which I am very proud to be one.
==================================================
And I for one am really glad you’re here, thank you!
LightRain says: at 5:08 pm RE: names
1978 was the last year all female names were used for Atlantic hurricanes. After 1978 the number of possible names essentially doubled. Thus, retiring a name does not have the same “hit” to the list that it did before 1978. Perhaps this has something to do with the issue although I have no actual information. In any case, the comparison you make ought not to extend back beyond 1979.
Chris in Ga says:
September 12, 2010 at 6:06 pm
> So is that Ee-gor or Eye-gor??
I believe it’s supposed to be Ee-gor, but since the initial letter is so important, go ahead and call it Eye-gor. Just don’t call it Al-Gore.
Now let’s watch the latent heat get sucked into the atmosphere then radiated out into space…
Aiding further cooling?..
Ok thx for the feedback, i didn’t mean to be too critical i am an avid reader from the UK and fortunately we don’t need to look at the sky here and wonder if it might kill us today. So I apologise for dishing hurricanes.
I have been reading this blog since dec 09 and find it fascinating and have learnt many things however with this new found knowledge i find that most people i speak to are completely ignorant of climate and the political implications and tend to be happy with what they are told via their politicians and media. I often wonder why people don’t do any research of their own or question anything.. Is the dumbing down of tv, news and education to blame. In order to stop all this nonsense we need to get man thinking again.
I have always rated this site and SteveMc’s as the tops and the quality of real scientist they both attract is witness to me being right.
Anthony and the gang put in an enormous amount of work to make this site lively, active and dynamic and it works brilliantly. If not for that it would be a realclimate site, yuk!!
Thanks guys and thanks Ryan for your many contributions.
Max says:
September 13, 2010 at 2:01 am
“[…] i find that most people i speak to are completely ignorant of climate and the political implications and tend to be happy with what they are told via their politicians and media. I often wonder why people don’t do any research of their own or question anything.. Is the dumbing down of tv, news and education to blame. In order to stop all this nonsense we need to get man thinking again.”
I’ve found it to be much the same here in the U.S. None of my social circle seems interested or discusses climate, how or why climate changes, nor do they seem particularly concerned (or convinced) about CAGW. My friends aren’t dummies by any stretch. They just don’t seem care either way because despite all the alarm bells ringing in the media, they don’t see anything out of the ordinary happening. They’ll jump one way or the other on the issue when either the politicians go after their wallet or they see the ocean swallowing up vast tracts of coastline.
Guess which one is happening first here in the good ol’ U.S. of A.?
Why are most people disinterested in climate studies or CAGW here in the US of A? I believe it is a case of rampant common sense and rational self interest. For all of the ink, video (tape and film) and blogging space spent on Man caused global warming the average guy looks around him and sees no impending disaster. He hears another politician saying that it is necessary to take more of his hard earned wages to fight the impending disaster he does not see himself and thinks, “Why isn’t this guy more worried about the economic problems all around me? My brother and sister have both been out of work for more than a year and this guy is worried about a possible problem years in the future?”
On top of that sites like this one have been asking the forbidden questions about global warming and let us all know that there has been all too little “science” done on Global warming. The people who come to this site have spread what they have learned to their associates and that has brought a lot more sunlight to the subject in the general population. The general population is disinterested in climate largely because they have no pressing need to become interested.
WOW! Looking at the trajectory, it looks as if it is headed straight for Florida. After living there for several years, I can say that this is definitely a scary prospect.
_I_ said:
LOOK OUT EAST COAST !
… Doomsaying does work occaisionally but this was no 1-in-8 chance.
100%.
All this year I’ve been telling everyone Saharan Dust Storms are raised by Strong El Ninos & supress Hurricanes, so this year would be no Record breaker. Of course this is a Rule of Thumb I read elsewhere which explains why 1998 was so Hot, yet the “canes were Not.
But the Wind turned south a few days & Earl slipped through, now it is South, erratically, most of the last Several Days.
Note the 30-day is starting to show gaps but still shows Saharan Dust Well into the Carribbean.
That is – – or Was – – a “Dust-i-cane” !
>> Track the Dust at: http://www.osdpd.noaa.gov/ml/air/index.html.
PS: the Air may be in the “Cold La Nina” pattern = many small storms, moving up the East Coast – – but warm El Nino water moving around Africa has a time-lag of about 6 months – – still energizing any storm not killed by the Dust = “many Big storms, moving up the East Coast”.
Pray for West Winds.
On weather and climate issues the best advice for NOAA guys: Very early in the morning, before going to work, check WUWT, and confidently, after arriving at your office, you can make your forecasts.
I really hate to mention this (I really do !) but notice that Igor IS NOT FOLLOWING EARL/FIONA so he has a nice bunch of not pre-cooled ocean surface water to feed off.
I just thought y’alls might find that interesting.
Richard Holle says:
September 12, 2010 at 6:48 pm
….I am testing a new hypothesis, I didn’t know how sound it was without testing it, I will see how it turns out at the end of the season as to how much of it was wrong and by further modification with more data.
Nothing ventured nothing gained.
______________________________________________
At least you admit it is a hypothesis. And then put you reasoning and predicts out there for all to see and take pots shots at.
Thanks for showing others how it should be done.
Ee-gor or Eye-gor? Reminds me of:
Sorry for the OT – as you were.
George E. Smith says:
September 13, 2010 at 8:32 am
I really hate to mention this (I really do !) but notice that Igor IS NOT FOLLOWING EARL/FIONA so he has a nice bunch of not pre-cooled ocean surface water to feed off.
I just thought y’alls might find that interesting.
___________________________________________________________-
Yes but think of all that Ocean Heat Content she is going to dump into outer space. It is a she because it is a HERricane after all. I wonder if she will follow the female prerogative and do something not predicted.
From Hurricane Igor discussion number 22
The UW-CIMSS secondary eyewall formation index strongly suggests that a secondary eyewall will form in the next day or two.
Eyewall replacement cycles are interesting events in the life of a large hurricane. Ryan Maue may have much to fault in my mental model (and please do!), but I’m sure he finds them fascinating too.
I view a hurricane’s eyewall as a cylindrical (funnel shape as you go higher) surface where the force of the low pressure sucking in air equals the centripetal force required to keep air moving circularly. For the eye to shrink in diameter, it needs a lower pressure, and pulling air in closer speeds it up (ye olde skater spin model) and more force is required at the smaller, faster diameter.
So at the eyewall, air has no place to go but up, but there are limits to how much can be lifted, and things begin to back up. That changes the pressure profile along the radius and the gradient weakens near the eyewall. Eventually, the weaker pressure can’t suck air all the way to the eye, and a new eyewall forms. The air inside the new wall gets flushed out, or even sucked into the new eyewall and pretty soon the old eyewall dissipates and we’re left with a hurricane with a larger, weaker eye.
If overall conditions haven’t changed, the pressure will drop, the eye shrinks, and the maximum windspeed makes it back to the original speed and the eyewall replacement cycle is complete.
——
Mostly on a different matter, I like to look at the unenhanced visible and IR photos of hurricanes. The IR photo show cold cloud tops as white so it shows the cirrus outflow from a storm. OTOH, the visible image sees through the thin cirrus and you can see deeper into the storm.
The eye photos are dramatically different now, and you can begin to see the “stadium effect” of the funnel shaped eye in the visible photo.
http://www.nhc.noaa.gov/satellite.shtml
http://www.ssd.noaa.gov/goes/flt/t1/vis-l.jpg
http://www.ssd.noaa.gov/goes/flt/t1/ir4-l.jpg
If you can, check out the visible photo near sunset, that brings out the storm’s structure the best.
I like hurricanes to have powerful scary names. I think “Hitler” would be perfect for a cat 5 “H” storm. Ivan (the terrible) is a good I name, too bad it’s been used so much already. Igor is a variant of the god Ingvar, so there’s power. But that god was for peace and fertility, so not so scary.
As following Richard Holle’s theory, the moon is too far down there yet: Today’s declination -23. Igor will be waiting for some power until sept.22.
Tommy says:
September 13, 2010 at 10:55 am
I like hurricanes to have powerful scary names. I think “Hitler”
Don’t you think “AL” would work?
Enneagram says:
September 13, 2010 at 10:56 am
Reply;
Actually Igor is peaking on the secondary lunar tidal effects, and has about 2 more days to tap into the additional benefit of riding the secondary tidal effects before the tide turns on the 15th and the primary bulge in the Southern hemisphere starts back North again.
Usually this forms the start of the more rapid progression of the turn to the NW, North, North East sweep toward the poles, by the time the moon crosses the equator.
I missed forecasting this surge of hurricane production, Igor and the next wave coming off of Africa, due to over consideration of the length of time the outer planets would be able to over come the natural declinational modulation, because the declination at culmination is so close to 23.5 degrees, the power contained at this midpoint of oscillation is more than it has been in the past couple of years.
I made the mistake of going with my gut feelings from watching the past three years of production, rather than waiting to get all of the daily ACE data processed completely, so as to have DATA as the primary reasoning factor, and I got caught out.
I am waiting to see if the rest of the anticipated, and already described outer planet influence comes about as stated, as I fatten several crows I have in a pen. Still processing data Ryan Maue was kind enough to give me the location of. If I had better programmer abilities or support, I would not be having to hand enter / transfer the daily data values into the spread sheet slots.
Some times the need to take some kind of action NOW, before being fully prepared is not the best course of action.
“”” Gail Combs says:
September 13, 2010 at 10:04 am
George E. Smith says:
September 13, 2010 at 8:32 am
I really hate to mention this (I really do !) but notice that Igor IS NOT FOLLOWING EARL/FIONA so he has a nice bunch of not pre-cooled ocean surface water to feed off.
I just thought y’alls might find that interesting.
___________________________________________________________-
Yes but think of all that Ocean Heat Content she is going to dump into outer space. It is a she because it is a HERricane after all. I wonder if she will follow the female prerogative and do something not predicted. “””
Well far be it from me to deny Mother Gaia the full credit for this spectacle; and in any case I wouldn’t want to incite the wrath of the woman scorned; so if Y’alls want to take credit for the mayhem Gail; I’ll stand aside; actually I’ll cheer you on; things need a little shaking up occasionally.
Dunno where folks are getting the eye-gore from though; I thought the standards of English teaching were a bit ahead of that.
Come to think of it a lot of folks want to use eye-nez for Ynez despite the fairly straight forward rules for Spanish “vowels”. My MIL would lynch me if I said eye-nez.
According to Stormpulse , all models but one show Igor curving to the NNE towards Bermuda . The outlier is from the Canadian Meteorolgical Centre . Ditto for TS Julia , except that Julia is currently forcast to the east of Bermuda . What does the CMC see that others don’t ?