I was an AF aviation weather forecaster for 12 years, then 15 years as a dropsonde systems operator with the AF Reserve Hurricane Hunters.
By: Randy Bynon , 5:07 PM GMT on August 26, 2012
All eyes are on Isaac this afternoon as it makes its way through the Florida Keys as a tropical storm. Current Key West radar shows the storm circulation very well though it still appears a bit ragged in terms of deep convection and eyewall development. But Isaac is now entering the Gulf which is quite warm. A ridge is building in over the SE US. Water vapor and visible loops show the ridge is beginning to effectively stall out the trough over the southern plains that might have a chance to pull Isaac north. As a result, the models have shifted west as has the NHC forecast track. I wouldn't be surprised to see the track shift a bit further west before landfall sometime Tuesday night.
At this point, the models are merging on the track forecast through 72 hours. There is some divergence in the models at the 72 hour point but that divergence is based on the differences in the way the models handle the trough. The intensity forecast is fairly straight forward. Water temps in the Gulf are more than warm enough to support development and wind shear is forecast to be fairly low for the entire track across the Gulf. The biggest issue that Isaac might have in intensifying is the lack of core organization at this point and the extent to which the storm is spread out. Interaction with the Keys and the SE FL peninsula will slow down immediate intensification. Systems spread out as broad as Isaac typically have a tough time getting organized quickly. The short distance (relatively) between Isaac's current position and i's forecast landfall position doesn't give the storm a lot of time to consolidate and build before it makes landfall. If Isaac follows the forecast path through my backyard, I don't think it'll have the chance to be much more than a cat 2 hurricane. If the track shifts much further west, that'll give the system a bit more time over warm water and it might be able to reach a weak cat 3.
Having said that, even a cat 2 is a storm to be reckoned with. Please take seriously all watches and warnings posted for your area.
I'll post again tonight after the 11pm EDT advisory.
Have a great day!
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