Hurricane Irene pounds Puerto Rico, heads for Hispaniola

By: Dr. Jeff Masters , 2:40 PM GMT on August 22, 2011

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Hurricane Irene strengthened into the season's first Atlantic hurricane at 5am EDT this morning as the eye moved over San Juan, Puerto Rico, and crossed into the ocean just north of the island. Overnight, Irene held its own as the eye passed over the most mountainous portion of Puerto Rico, the El Yunque region. Winds in the higher mountains likely reached Category 2 strength, 96 - 110 mph, according to measurements from the San Juan Terminal Doppler Radar, and the hurricane pounded the island with damaging winds and flooding rains, resulting in widespread tree damage and power failures that hit 800,000 people. The San Juan Airport recorded top winds of 41 mph, gusting to 55 mph, and 2.87" of rain, as of 9am AST. Tropical storm conditions affected the Virgin Islands, with St. Thomas recording sustained winds of 40 mph, gusting to 67 mph, and 4.03" of rain as of 6am AST today. At 7am EDT, the ship Horizon Trader measured sustained northeast winds of 69 mph and wave heights of 11.5 feet at 19°N, in the northern eyewall of Irene. Latest observations from an Air Force hurricane hunter aircraft indicate that Irene is slowly intensifying, with a central pressure of 989 mb observed at 9:42am EDT. The eyewall is not fully formed yet, with a gap on the south side. This gap will need to close off before the hurricane can undergo rapid intensification.


Figure 1. A direct hit: the center of Hurricane Irene passed directly over the Terminal Doppler Radar at San Juan, Puerto Rico between 4am and 5am AST this morning.

Track forecast for Irene
The computer models show good agreement that Irene will pass along the north coast of Hispaniola today, but just a slight wobble in Irene's track to take it farther offshore--or push it onshore, over the mountains--will have major impacts on the ultimate path and strength of the hurricane. A trough of low pressure is expected to move across the Eastern U.S. on Wednesday and Thursday, turning Irene more to the northwest by Wednesday. The timing and strength of this trough varies considerably from model to model, and will be critical in determining where and when Irene will turn to the north. Irene's strength will also matter--a stronger Irene is more likely to turn northward earlier. The most popular solution among the models is to take Irene to the northwest through the Bahamas on Wednesday and Thursday, then into the Southeast U.S. coast in South Carolina or North Carolina on Saturday. Irene would then travel up the mid-Atlantic coast, arriving near Long Island, New York on Monday morning as a strong tropical storm or Category 1 hurricane. One of the models proposing this solution is our best model, the ECMWF. However, we have two other of our very good models suggesting a landfall near Miami on Thursday night is likely (the GFDL and UKMET models.) NHC forecaster Stacy Stewart gave some good reasons in this morning's discussion to favor a track close to the east coast of Florida, but just offshore. Last years' worst performing major the model, the NOGAPS, predicts that Irene will pass out to sea, missing the Southeast U.S. coast. Keep in mind that the average error of a 4-day forecast from NHC is 200 miles, and just a small deviation in the path of a storm moving roughly parallel to the coast will make a huge difference in where it ultimately makes landfall. The NOAA jet will be flying its first dropsonde mission into Irene today, which should result in a more reliable set of model runs first thing Tuesday morning.

Intensity forecast for Irene
Irene is embedded in a large envelope of moisture now, and wind shear is expected to remain low, 5 - 10 knots, for the next five days. With water temperatures very warm, 29 - 30°C, these conditions should allow for intensification except when land is interfering. Satellite loops show that Irene is steadily growing in size, which will protect the storm against major disruption by its passage along the north shore of Hispaniola today. The storm is lacking much development on its southwest side, where dry air is interfering with development. This dry air may help keep southern portions of the Dominican Republic and Haiti from receiving more than 3 - 6 inches of rain. There is at least a 30% chance that passage of the eye over Hispaniola will reduce Irene to a tropical storm tonight and into Tuesday. Due to Hispaniola blocking inflow of moist air from the south, Irene will likely compensate by building an even larger region of heavy thunderstorms to the north, offshore. Thus, when Irene's center finally moves well away from the coast on Tuesday, it will be a bigger storm, with the potential to spread hurricane conditions over a wider area later in the week when it intensifies. One limiting factor for intensification may be in the upper-level outflow pattern. The hurricane is lifting a huge amount of air from the surface to the upper atmosphere, and all that mass has to be efficiently transported away in order for the hurricane to intensify. Right now, upper level outflow is only well-established to the north and east, and the forecast outflow pattern for the coming five days is only moderately favorable. Overall, I think the official NHC forecast of a Category 3 hurricane by Thursday is the right one, though Irene could easily be a Category 2 or Category 4 storm.

Irene's impact on the Dominican Republic
Heavy rains from Irene have already reached the eastern tip of the Dominican Republic, where Punta Cana has seen wind gusts up to 29 mph this morning. The northeast coast of the country near Samana will receive the worst of Irene's wrath, with sustained winds of 50 - 70 mph and gusts above hurricane force likely to cause widespread tree damage and power outages today. Passage along the coast of the island may weaken Irene to a tropical storm by Tuesday morning, and wind damage in Puerto Plata may be less severe than at Samana. The capital of Santo Domingo will see lesser winds, perhaps 30 - 50 mph, with gusts to 60 mph. The main danger to the Dominican Republic will be Irene's torrential rains, which are likely to reach 20 inches in some mountainous regions, causing dangerous flash floods and mudslides.

Irene's impact on Haiti
No nation in the Caribbean is more vulnerable to hurricanes than Haiti, whose northern reaches are expected to receive torrential rains of 5 - 10 inches from Irene. During the 2008 hurricane season, four storms--Fay, Gustav, Hanna, and Ike--dumped heavy rains on Haiti, leaving over 1,000 people dead or missing. The path and intensity of Hurricane Irene are very similar to that of Hurricane Jeanne of 2004, which dumped 13 inches of rains on the nation's northern mountains. The rugged hillsides, stripped bare of 98% of their forest cover thanks to deforestation, let flood waters rampage into large areas of the country, killing over 3000 people, mostly in the town of Gonaives, the nation's 4th largest city. Jeanne ranks as the 12th deadliest hurricane of all time on the list of the 30 most deadly Atlantic hurricanes, and Irene's rains are capable of causing a similar disaster. During 2004 and again this year, ocean temperatures off the coast of Haiti were 1 - 1.5°C above average, one of the top five values seen in the past 100 years. Since more water vapor evaporates into the air from record warm waters, the potential for devastating floods from hurricanes is much higher in these situations. However, satellite images of Jeanne show the storm had much more moisture on its south side when it hit Hispaniola than Irene currently has, so I am hopeful that Irene's rains will not be as intense as Jeanne's were.


Figure 2. Track of Hurricane Jeanne of 2004, which followed a path very similar to what is expected from Hurricane Irene along the north coast of Hispaniola. Irene is not going to do a big loop like Jeanne did, though.

As bad as the hurricanes of 2004 and 2008 were, the January 2010 earthquake was far worse. Up to 316,000 may have been killed, and the capital city of Port-Au-Prince was devastated, leaving over 1.5 million people living under tarps during the 2010 hurricane season. Fortunately, Hurricane Tomas missed making a direct hit on Haiti, and Haiti escaped major loss of life during the 2010 hurricane season. This year, approximately 595,000 Haitians still live underneath tarps outdoors thanks to the earthquake, and these unfortunate people will be at risk of being swept away by flash flooding from Irene's torrential rains. However, Port-Au-Prince lies to the south of where Irene's main rains will fall, and I doubt the earthquake refugee camps will suffer from a major flooding disaster.


Figure 3. Hospital admissions (black bars) and death rate in percent (red line) for Haiti's cholera epidemic of 2010 - 2011. The cholera epidemic surged out of control after Hurricane Tomas dumped heavy rains on Haiti on November 4, 2010, with hospitalizations increasing by a factor of three for over a month. Over 3% of all people who contracted cholera died after Tomas' rains. However, sanitation and medical care improved in the following months, and the death rate fell by a factor of five to 0.7% by the summer of 2011. Another surge in cholera cases occurred in June 2011, doubling after heavy rainy season rains occurred. Cholera deaths doubled during the surge, but the death rate remained constant at 0.7%. Image credit: Pan American Health Organization.

Another danger is that Irene's rains will worsen the cholera epidemic that surfaced after the earthquake. Cholera is a water-borne disease, and spreads readily after heavy rains. As of August 12, 2011, the 2010 - 2011 cholera epidemic had infected 419,000 Haitians, killing 5,968. After Hurricane Tomas passed on November 5, 2010, cholera cases exploded, with hospital admissions more than tripling for over a month. Similarly, heavy rains in June 2011 during the country's usual rainy season caused doubled cholera cases and deaths for several weeks. We can expect that Irene's rains will cause at least a doubling of cholera cases for a month or more. This will lead to several hundred additional cholera deaths, given the disease's 0.7% mortality rate this summer in Haiti (during June and July 2011, 95,212 cases were reported, with 626 deaths.) An increase in cholera deaths due to Irene's rains is also a concern in the Dominican Republic, where cholera has sickened 14,000 people and killed 92 as of the end of July.

Organizations Active in Haitian Relief Efforts:
Portlight disaster relief
Lambi Fund of Haiti
Haiti Hope Fund
Catholic Relief Services of Haiti

Links
For those of you wanting to know your odds of receiving hurricane force or tropical storm force winds, I recommend the NHC wind probability product.

Wunderground has detailed storm surge maps for the U.S. coast.

See my 2010 post, Haiti's tragic hurricane history.

An exceptionally active of hurricane season
Hurricane season is only one-third over, and we've already had almost a full years' activity already. Tropical Storm Irene is the 9th named storm this year, and an average season has just 10 - 11 named storms. Irene's formation date of August 20 ties 2011 with 1936 as the 2nd earliest date for formation of the season's 9th storm. Only 2005 was more active this early. However, the first eight storms of the year have done far less damage than is typical. All eight storms stayed below hurricane strength, making 2011 the first hurricane season since record keeping began in 1851 to have more than six consecutive tropical storms that did not reach hurricane strength. As I discussed in Friday's post, a major reason for this is the lack of vertical instability over the tropical Atlantic so far this year. We've had a large amount of dry, sinking air over the tropical Atlantic, and the usual amount of dry, dusty air from the Sahara, both helping to keep the atmosphere stable and stop this year's storms from intensifying into hurricanes. Hurricane activity typically ramps up big-time by August 20, with more than 80% of all the hurricanes and 65% of all the tropical storms occurring after that date. At our current pace, 2011 will become the second busiest Atlantic hurricane season on record, with 24 - 27 named storms. There are only 21 names in the list of names for a hurricane season, so we may have to break out the Greek alphabet again in late October this year, as occurred in 2005. Ironically, this was the last time the current set of names was used in the Atlantic, so 16 of this year's 21 names are repeats of 2005. I'm not too happy about seeing another hurricane season challenge the Hurricane Season of 2005 in any way, and let's hope we don't retire another five names this year, like occurred in 2005! With vertical instability much lower this year than in 2005, and that year having already seen one storm (Dennis) retired by this point in the season, I doubt that will happen, though.


Figure 4. The annual cycle of average hurricane frequency in the Atlantic. Historically, about 35% of all the tropical storms and 15% of all the hurricanes will have occurred by August 20.

Which model should you trust?
Wunderground provides a web page with computer model forecasts for many of the best-performing models used to predict hurricane tracks. So which is the best? Well, the best forecasts are made by combining the forecasts from three or more models into a "consensus" forecast. Over the past decade, NHC has greatly improved their forecasts by relying on consensus forecast models made using various combinations of the GFS, GFDL, NOGAPS, UKMET, HWRF, and ECMWF models. If you average together the track forecasts from these models, the NHC official forecast will rarely depart much from it, and the NHC forecast has been hard to beat over the past few years. The single best-performing model over the past two years has been the ECMWF (European Center model). This model out-performed the official NHC forecast in 2010 for 1-day, 2-day, 3-day and 4-day forecasts, and in 2009 for 4-day and 5-day forecasts. You can view ECMWF forecasts on our wundermap with the model layer turned on. The European Center does not permit public display of tropical storm positions from their hurricane tracking module of their model, so we are unable to put ECMWF forecasts on our computer model forecast page that plots positions from the other major models. As seen in Figure 5, over the past two years, the GFS and GFDL model have been the next best models, with the UKMET model not far behind. Last year, the NOGAPS model did very poorly, forcing NHC to come up with some new consensus models this year, the TCOA and TVCA, that do not include the NOGAPS model. For those interested in learning more about the models, NOAA has a great training video (updated for 2011.)


Figure 5. Skill of computer model forecasts of Atlantic named storms 2010. OFCL=Official NHC forecast; GFS=Global Forecast System model; GFDL=Geophysical Fluid Dynamic Laboratory model; HWRF=Hurricane Weather Research Forecasting model; NOGAPS=Navy Operational Global Prediction System model; UKMET=United Kingdom Met Office model; ECMWF=European Center for Medium Range Weather Forecasting model; TVCN=one of the consensus models that lends together all (or most) of the above models. Image credit: National Hurricane Center 2010 verification report.

Next post
There will be 2 - 3 posts per day in my blog this week during Irene, with Angela Fritz and Rob Carver doing some of the afternoon and evening posts.

Jeff Masters

Tropical Storm Irene hits Puerto Rico (lobdellJ)
Tropical Storm Irene hits the north coast of Puerto Rico
Tropical Storm Irene hits Puerto Rico
Tropical Storm Irene from Maunabo, PR (ronmil)
The first bands or Irene approaching Maunabo, Puerto Rico (SE corner)...
Tropical Storm Irene from Maunabo, PR
Irene (reefchild)
Irene @OPkB OceanParkBeach Puerto Rico 7pm
Irene

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If a post appears to be one that you, and others, just HAVE to respond to, that is a great indication that you are reading the drivel of a troll. One that is intentionally writing provocative comments so that someone will talk to them and confirm that what they wrote is being read.

If it works, they are happy and continue to do their bidding here.

Don't be that someone. Let them go somewhere else to find that someone that will actually talk to them and read their drivel.
Member Since: August 16, 2007 Posts: 6 Comments: 12463
Quoting Gorty:
Hate to say it, but looks like the dry air is going away or it is moving with the storm so I doubt it will affect her much.
Already sucked some in by the look of the dry slot in the NW quad of Irene.
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384. 7544
gfs here she comes here she come opps there she goes lol
Member Since: May 6, 2007 Posts: 0 Comments: 6874



almost right on the NHC track
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Quoting chevycanes:
main radar in PR is working again.


Thanks for the update I was looking forward to that all morning.
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Well.. this would end our lack-of-major US landfall streak.
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12z gfs at 102hrs. Link
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Fairly healthy trough depicted on the 500mb and surface map of the GFS 12z:

Member Since: October 28, 2006 Posts: 57 Comments: 30813
Quoting RachelP:


At that time I was living just south of Bridge Rd in Hobe Sound. Hopefully this isn't going to be a repeat performance. I've moved up to Central Fl now though.


Ah! I'm in Port Saint Lucie. Just got married and bought a house this past year. A little nerve-wracking to say the least. I hope the more easterly track holds true.
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09L/H/I/C1
MARK
19.26N67.86W





ALWAYS FOLLOW NHC/TPC FORECASTS FOR ALL WARNINGS REGARDING THIS STORM
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Quoting blueafuze:
The only real thing you can count on is the next 24hrs in the cone. You dont know what will come tomorrow. To many times have I seen a hurricane do what its not supposed to do to rely solely on the models. Irene could stall tomorrow and sit for 2 days. The experts will say "do to unforseen ridging"....blah blah blah. Expect the track to change...It may change from GA, to NC back to FL. If your in front of Irene, please just stay informed to your local stations and be ready. Dont wait for surprises.


You can't always rely on 24 hours out, especially when dealing with intensity. I vividly remember Dennis. I had five kids under 9 years old and had evacuated for so many in the last couple of years that when it was "only" a cat 2 in the gulf and not predicted to get stronger before landfall I decided to ride it out. Bad mistake. My earlybird friend called at 4:30 am to tell me it was now a cat 5! I ended up riding it out in a convent with four foot cement walls. Ultimately it was a non-event for Mobile, but it sure did tear up our eastern shore! Now I live very close to the gulf and evacuate early.
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Quoting ralphmtsu:
I find it ironic that the NOGAPS model seems to be performing quite well with Irene. I think it has consistently had Irene on more of a WNW track-- sooner than most other models. I seem to remember the GFS and other models wanted to take Irene south of PR and even south of the DR and Haiti. Looks like Irene could quite possibly miss direct impact on Hispanola. Depending on the low pressure trough, Irene might miss the US and just ride up the east coast 75-100 miles out to sea.



what model do you see that shows that? what trough will be strong enough to yank it that hard of a fishhook. i don't see potential in what you are saying.


also, if this thing gets huge 100 miles off the coast will be worst case scenario....if it does that up and down the coast it will strengthen as it lays into town after town with hurricane force winds. katrina's diameter was huge and this could be bigger considering the goldielocks environment and the heat of the gulf stream it is traveling through.
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374. Gorty
Hate to say it, but looks like the dry air is going away or it is moving with the storm so I doubt it will affect her much.
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GFS farther east on this run.
Member Since: October 28, 2006 Posts: 57 Comments: 30813
372. 7544
big shift east on the gfs wow the trof is going to be strong
Member Since: May 6, 2007 Posts: 0 Comments: 6874
Quoting USAFwxguy:
Went back through to check and nobody covered the CIMMS update.

Notice at low levels that the trough is seen lifting out and the ATL ridge is nosing toward the west, to the north of Irene:

-3hr


Current:


Also of note is the TX high eastern periphery weakening.
Seems the implications would be a wnw track for a little longer than expected ??
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Quoting USAFwxguy:
Went back through to check and nobody covered the CIMMS update.

Notice at low levels that the trough is seen lifting out and the ATL ridge is nosing toward the west, to the north of Irene:

-3hr


Current:


Also of note is the TX high eastern periphery weakening.


That will be the key the next 24 to 48 hours, but the final shortwave to move down and give Irene that kick East of Florida is still over North and South Dakota...Link
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Afternoon! Lost internet all day yesterday, had to resort to TWC for updates, but Irene has had some land interaction.. but its our first hurricane of the season!
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If (and I realize it's a big "if" this far out) Irene were to make it up to the Northeast what would be the approximate time frame on that ?

I have some geology field work to conduct later this week and into early next week and I'm starting to wonder whether it might be something that I should look at postponing (the work will be severely impacted by heavy rain if that's what we received out of the storm).

Thanks everyone for the valuable information and discussions regarding all things weather related !
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In the near term. The radar if Irene looks like this might affect more of the DR then anticipated. Those people and Haiti really don't need this rain with all the suffering there:o
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Quoting rushisaband:




thanks for all the loop de loops you post. btw ran my generator for 10-15 minutes this weekend. have not needed it the past several years, but you know it is just a matter of time. p'cola here


A good seasonal ritual,,or "running of Da jenny"
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While all eyes are on Irene,(& rightly so)anyone have thoughts on the TW just emerging off Africa? TIA
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Quoting cruzinstephie:


Actually it made landfall in Martin county, about an hour south of the Space coast. The center of the eye came in the St. Lucie inlet, 3 weeks to the day after Francis at nearly the exact same point of landfall. Not a fun year. I was without power over two weeks between the two storms.


At that time I was living just south of Bridge Rd in Hobe Sound. Hopefully this isn't going to be a repeat performance. I've moved up to Central Fl now though.
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363. 7544
gfs wave by by by
Member Since: May 6, 2007 Posts: 0 Comments: 6874
I suspect Levi's arrival is imminent....
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Quoting USAFwxguy:
Went back through to check and nobody covered the CIMMS update.

Notice at low levels that the trough is seen lifting out and the ATL ridge is nosing toward the west, to the north of Irene:

-3hr


Current:


Also of note is the TX high eastern periphery weakening.



and what will that cause???
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Very new to all of this, but I think that I may understand, when I take everyone's pov into consideration, is saying is the track of Irene will affect the strength of Irene...and the strength of Irene will determine how she is affected by the troughs and steering currents, which will then affect track of Irene? Is that close?
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Quoting Patrap:




thanks for all the loop de loops you post. btw ran my generator for 10-15 minutes this weekend. have not needed it the past several years, but you know it is just a matter of time. p'cola here
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Irene even got a mention in Lake Charles discussion this morning:


FOR THOSE THAT ARE LOOKING TO THE SE...IRENE WILL NOT HAVE ANY
EFFECT ON THIS REGION AS IT MOVES TOWARDS THE EAST COAST OF THE
US.
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12z GFS still holding east at 72 hrs
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Oh well, if Cantori or Seidel are headed this way, Irene is guaranteed NOT to come to Florida. Well, maybe just brush us with a little wind.  But just in case, have updated my emergency supplies: water,check; pop tarts,check; chips, check; generator/gas,check; kitty food,check. Yep got it covered.
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Quoting HurricaneKarl:
24 - 48 hours ago Irene looked like it might make Cat 1 at best. No we are looking at a potential Cat 3.

1) Why have conditions changed to allow for such intensification.
2) Coudl this get more intense than a 3 (I'm remembering Floyd as a 5 before moving north and missing Florida).
3) At present this looks a threat to teh Carolina's. What would need to happen for this to hit Florida, is it just a case of not nmaking the turn north in time?


1) Conditions haven't changed, but the track has shifted. 24-48 hours ago the track was forecast to have Irene move over Hispaniola, weakening it, then moving it over south Florida, before it had time for much intensification. Irene is now forecast to miss Hispaniola, and curve to the north before Florida. This gives much more time and space over warm water for intensification, hence the Cat 3 forecast.

2) It could get more intense than a 3, water is very warm and shear should be low. However, 3 is probably the most likely at this stage.

3) If the trough didn't dive as far south, or moved out a little faster than forecast, the high could build west quickly and push Irene towards Florida. That is looking less likely at this time, however.
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main radar in PR is working again.
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Storm Relative 1km Geostationary Visible Imagery


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I find it ironic that the NOGAPS model seems to be performing quite well with Irene. I think it has consistently had Irene on more of a WNW track-- sooner than most other models. I seem to remember the GFS and other models wanted to take Irene south of PR and even south of the DR and Haiti. Looks like Irene could quite possibly miss direct impact on Hispanola. Depending on the low pressure trough, Irene might miss the US and just ride up the east coast 75-100 miles out to sea.
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12z gfs at 72hrs. Link
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Where's Levi? Is he, at the moment getting paid to observe and report? I totally get his priorities if so. I'm curious to see his insight a lot right now. He saw the shift to the Carolinas yesterday, wonder if today he is seeing anything additionally or differently.
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Quoting jeffs713:
So if all the bloggers wishcasting a FL landfall were to blow hot air to the east, would it make Irene stronger, or just push her to the east?


How can you say that it is wishcasting when Florida is in the cone?
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The Florida peninsula is only about 140 miles wide at the wider points. Also, from the West coast of Florida to the East side of the northern Bahamas is only about 320 miles, total. If Irene increases in size and strength as forecast, it's very possible that much of the Florida peninsula and the Bahamas will receive Tropical Storm force winds, at the very least, and some areas will certainly receive Hurricane force winds. So please do not say, or even think, that any part of the Florida peninsula is 'out of danger' because it simply is not true. Plan for safety now.
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Quoting Neapolitan:
So I reckon Irene is likely to give the US its record tenth billion-dollar weather disaster this year, huh? :-\


Maybe she we'll get so strong she turns north and east to the point to where she may miss everything. Storms in that area have done that before. We can only hope it does. Everyone from NC to Miami needs to be getting their ducks in a row. Fill your vehicle up NOW, so that you wont have to later!
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Quoting atmoaggie:
Oh, and two more. A great many surface observation platforms do not actually have an anemometer AT 10 meters, but a lower one with some reasonable adjustment. While reasonable, the adjustment isn't always accurate and very rarely accounts for the roughness upstream by the specific direction of the wind.

(Obviously the airport official ASOS should be 10 meters).

And, the issue of time averaging. ASOS is a 2-minute average, I think. NDBC buoys, 8-minute average. C-MAN coastal stations vary. Other weather stations, mixed bag of who know what.

All time averaging acts to reduce the magnitude below that of 1-minute. The longer, the less.


Thanks for clearing things up for me.
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Recon. aircraft continuing to indicate that Irene is moving west-northwestward.
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Quoting HurricaneKarl:
24 - 48 hours ago Irene looked like it might make Cat 1 at best. No we are looking at a potential Cat 3.

1) Why have conditions changed to allow for such intensification.
2) Coudl this get more intense than a 3 (I'm remembering Floyd as a 5 before moving north and missing Florida).
3) At present this looks a threat to teh Carolina's. What would need to happen for this to hit Florida, is it just a case of not nmaking the turn north in time?


The potential was always there for a Major, but land interaction was the player for her not getting as strong. She took the jog North early yesterday and that changed the intensity forecast. I would say it could get to a 3/4 range. In order for her to hit Florida the Subtropical Ridge to Irene's North would have to strengthen and push West and/or the trough along the East Coast would not push as far South.
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Irene is slowly putting together her southern outflow channel as isolated thunderstorms are developing.
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337. Gorty
By looking at Satellite, she is affecting eastern Hispanola. Am right? Which also could be why her west and sw side is not looking good. I really don;t think the dry air is affecting her that much, its the land interaction.
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