MikeC
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The 11PM official track is out.
There is no real change to the forecast, it is just further along on the points in time, nor changes to watches and warnings.
It appears that the hurricane center is waiting for the next model runs with the Gultstream and Air Force dropsonde data to make any real change, which seems wise.
The Intensity forecast is up in the near term, now a cat 4 projected over the Bahamas, then it weakens to cat 3 north, and eventually approaches the NC/SC border Saturday evening.
If tropical storm or hurricane watches were to go up for Irene in Florida, they would likely come sometime tomorrow afternoon to fit in the 48.watch window.
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Random Chaos
Weather Analyst
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Loc: Maryland
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NHC intensity forecast:
INIT 23/0300Z 19.9N 69.2W 85 KT 100 MPH
12H 23/1200Z 20.4N 70.6W 95 KT 110 MPH
24H 24/0000Z 21.1N 72.4W 105 KT 120 MPH
36H 24/1200Z 22.2N 74.2W 110 KT 125 MPH
48H 25/0000Z 23.5N 75.6W 110 KT 125 MPH
72H 26/0000Z 26.5N 78.0W 115 KT 135 MPH
96H 27/0000Z 30.0N 79.0W 105 KT 120 MPH
120H 28/0000Z 33.5N 78.5W 100 KT 115 MPH
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danielw
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Quote:
NHC intensity forecast:
72H 26/0000Z 26.5N 78.0W 115 KT 135 MPH
That position is on the East End of Grand Bahama Island. And 80 miles east of West Palm Beach.
Worst of all it's at Sunset. 00Z
Edited by danielw (Mon Aug 22 2011 11:13 PM)
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danielw
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SENIOR DUTY METEOROLOGIST NWS ADMINISTRATIVE MESSAGE
NWS CENTRAL OPERATIONS CAMP SPRINGS MD
0315Z TUE AUG 23 2011
THE 00Z MODEL IS RUNNING ON TIME. RAWINSONDE COVERAGE FOR
MODEL DATA ASSIMILATION WAS EXCELLENT ACROSS NORTH AMERICA AND
INCLUDED 36 DROPSONDES FROM OVER THE CARIBBEAN SEA AND SOUTHWEST
ATLANTIC OCEAN.
36 extra points of data. Wow! That ought to boost the models.
Edited by danielw (Mon Aug 22 2011 11:23 PM)
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GuppieGrouper
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When will the data be available to the public and of course here on the Board? I mean will we see it in the morning or tomorrow night etc.?
-------------------- God commands. Laymen guess. Scientists record.
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danielw
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The data should help the models determine what is going on in the atmosphere surrounding Irene.
The only way we will see any effect of the data is for the models to converge more than they are currently.
However, lack of convergence doesn't imply the data was bad. It just reenforces the models being more correct.
In short. The data should improve the clustering of the model tracks. It won't change the size of the Cone. But it could change the location of the Cone. East or West.
Berrywr posted earlier in the Forecast Lounge that the Ridge near Bermuda had actually increased somewhat over a 12 hour span. In part due to Irene's outflow.
That's above my head. (No pun intended)
But my guess is that the outflow has moistened the atmosphere and changed the heights.
Or the outflow pumped the moisture out of the air at one level and increased it at another level.
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mwillis
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at 02:45 UTC on water vaper you can see an eye starting to form, or is formed. Doesnt that look like a small eye for a large system?
http://www.ssd.noaa.gov/goes/flt/t2/wv-l.jpg
eye is at 69 west line
Edited by mwillis (Mon Aug 22 2011 11:39 PM)
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berrywr
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I've analyzed the 500mb Upper Air Analysis with Plots and as many here have posted concern continues with whether Irene will turn north before becoming a real threat to FL or as some models continue to suggest a more westward track. This evening upper air data from Bermuda indicated a 10 meter increase to 594 decameters which continues to suggest the Bermuda subtropical ridge remains strong. A re-analyzing of the Mid-Continental "Texas" upper ridge continues to be entrenched over drought-stricken Texas. The east coast longwave trough lies between the two and is progressive however based on 20 meter height falls I've re-drawn the bottom of the trough to be across the northern FL where it ends near the upper ridge axis along 29N latitude. There remains a break in the ridge along a north-south axis near 27N 72W. NOAA9 extensively sampled the entire envelope ahead of Irene. The COL is centered once again near 27N 72W. It was noted on the 22/09Z discussion that if Irene reaches major hurricane status and with such a large circulation that outflow entering the westerlies to the north will also aid in keeping the upper ridge to the east strong again suggesting a closer approach to FL. New data this evening suggests this remains plausible. Intensity forecasting is problematic but Irene will be a major hurricane soon.
Larger version of image
Edited by MikeC (Mon Aug 22 2011 11:47 PM)
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LoisCane
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Okay so how similar to this set up was Floyd. Thanks for the analysis, and the effort you put in.
I'm concerned about some of the discussion which seemed to leave a wide door for variations in track over the next few days.
A category four storm off shore Miami by 100 .. 120 miles is really too close for comfort. Looking forward to the new model runs with the info from the Gulfstream Jet.
-------------------- http://hurricaneharbor.blogspot.com/
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ralphfl
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Well if the is any help with the new info it has shifted more east and northeast.in the new run.
With landfall in morehead city NC...
So the has shifted again EAST and a more north movement before landfall.
Edited by ralphfl (Tue Aug 23 2011 12:35 AM)
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Random Chaos
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Both dropsonde and flightlevel winds indicate the storm has weakened a little. Probably only about 85 to 90mph right now. Eyewall dropsonde showed 53kts at surface but may have missed the strongest wind. The eyewall is open southeast. Vortex recon report indicated the strongest winds at altitude were 83kt (95.55 MPH), which translates less at the surface. Given that it might have missed the strongest winds again, I'm giving an upper bound of 90mph surface.
However, pressure is down 3mb and IR shows the center reforming at the moment. My thought is this wind drop is transitory and she will be back to definite Category 2 shortly. Looks like there was some disruption of the southern feeders by the mountains of Hispanola which is being worked out of the system now. Once that is done, no reason for it not to strengthen again.
Edited by cieldumort (Tue Aug 23 2011 01:23 AM)
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WeatherNut
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At some point there will also be Eyewall Replacement Cycles. As mentioned earlier, the eye is rather small which is usually a sign that an will be coming on at some point. No one really can forecast these until they are happening
-------------------- Born into Cleo (64)...been stuck on em ever since
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scottsvb
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I really don't see much of a change with the dropsonde package. Never really changes a models output..maybe just slightly in the near term cause its always changing. That's why there is a mission again on Tues,Weds,Thurs..etc etc... with a trough digging in eroding the ridge, it wont matter how much heat gets pulled up into the ridge. Intense hurricanes like 950mb or lower has like 2% worth or less impact on the ridge or trough that approaches.
GFS 00Z run has actually again shifted back east to its 12Z run.
Main near term factor is the Failed pattern of the ridge over the past 3 days. has finally come inline with this ridge as of the 12Z run today and 0Z run by showing a more WNW movement (that it has had since Saturday). Others continued with a more W-WNW motion of 280dg except the HWRF but that model is usually on the right side of most runs.
Medium range will have the Cat3-4 Hurricane actually helping dig the trough on its western side pulling the Hurricane N and NE.. too early to say if there will be a landfall in the Carolinas.. SC-NC will get Tropical Storm conditions at least. Florida has a 5% chance of making a landfall or less even as I stated last Friday night.
Overall this is a typical run the coast between the US-Bermuda storm but is closer than normal due to it developing just east of the islands instead of east of 55W. Remember the didnt have this develop until Sat night in the SE carribean around 14-15N and 62-64W.. but this developed further north around 17N and 58W. Also ridging was more NE causing a WNW movement instead of the movement just north of due west that most models showed for Sunday-Tuesday.
In all....we have a Cat 2 that should be a Cat 3 on Tuesday and Cat 4 possibly over the next day or 2. Pretty much a straight shot into the bahamas and moving just east of Nassau in 3 days or less. Also note after the first short wave passes.. there is no ridging behind this short wave... so the strength of the ridge to the east of Irene will pull whatever is west of it N until the next short wave comes by this weekend into next week. But this isnt a forecast cause that is more than 4 days from now.
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