Wednesday, August 22, 2012

Tropical Storm Isaac and the Atlantic Blobette: August 21, Update B

Being out of town and in a science meeting meant I forgot that the Republican National Convention is in Tampa Bay next week. And of course the official center of cone current track of TS Isaac would be heading right for Tampa Bay for next week too. That is *exactly* how I would write this reality TV show.

But first, the Gulf blob I mentioned this morning has pretty much dissipated. It didn’t do anything sneaky so we’re all good and done there.

Here is a satellite image of the convection in the Atlantic for your viewing pleasure:

You can see Isaac, the Atlantic Blobette, and also the low pressure trough over Florida that I mentioned earlier (and below).

Tropical Storm Isaac
They finally named him after sending an aircraft into the system to check it was a Tropical Storm. Sigh. Really? The planes should be used when you really need them. Making that call should have been straightforward. Anyway, I’m sure the plane returned some good data so I’m ok with that bit. The other two changes since my last update are that they have shifted the track to the north, and that they have backed off on the intensification and now he won’t be a hurricane until Thursday evening, when they think it will be a lot closer to Puerto Rico.

He is currently officially at 15.6N, 55.6W moving W at 18mph. Winds are officially estimated to be 40mph, central pressure is 1006mb. So he is barely a Tropical Storm (range: 39-73mph).

He’s not a very well organized storm so it is a little difficult for me to see his center at the moment (it’s night time), but I think it is south of the official one… it looks like it is closer to 15.3N, 55.6W. Also, I think he is moving westward, although the center of cone track seems to take him WNW. If he actually is a little south and is moving more westward, then this means he’ll pass over a the Lesser Antilles an island or two south of the current center of cone track – maybe Dominica or Martinique - and there is a good possibility that the NHC might have his initial track (the next two days) a bit too far north. Regardless, they will all get some wet and very thundery weather! The track after Thursday is even murkier so although the lovely cone and center looks like it is heading for Tampa Bay, I would say wait a day or two longer. The problem is that low pressure trough (currently over Florida) that is moving in from the west. The models don’t know quite what to do with it and how it will impact the storm. If I had to tell you right now what was in my head for $1M (that seems a reasonable amount don’t you think?), I would say that he will do a pretty sharpish (for a storm anyway) northward turn in the Caribbean and head back into the Atlantic (on the east side of Florida) somewhere around Hispaniola, or possibly as far west as eastern Cuba, sometime on Friday or Saturday. But that is really truly just my speculation for tonight. You can send me a check for the $1M. ;-) Once he’s in the Caribbean (in less than 24 hours), we should have a much better idea (based on real data and whatnots!).

He is currently over water temperatures of 28 deg C with water warmer than 26 deg C in the upper 75-100m, which are both good for gradual intensification. However, he still has dry air in the northeast quadrant, and it looks like he might be going into a little wind shear as well as beginning to interact with the islands, which will all inhibit his intensification a little. At this rate he might remain a Tropical Storm until at least Friday.

Atlantic Blobette
This one is still following on the heels of Isaac. It is at around 11N, 32W heading W at 15mph. This has marginally less circulation than Isaac and a lot less convection as you can see in the satellite image. It is being impacted by the dry SAL to the north. The NHC give it a 70% chance of developing into a storm in the next 48 hours. This seems about ok… I think it will be a storm if it manages to cross the Atlantic to around where Isaac is now – so maybe in three days or so. Next name is Joyce.

Thanks to everyone who contacted me about storms today… I didn’t have time to get back to everyone but I’ll reply as soon as I can. Must. Nap. Now…zzzz….


Blogs archived at
Twitter @JyovianStorm

DISCLAIMER: These remarks are just what I think/see regarding tropical storms - not the opinion of any organization I represent. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast and the National Weather Service announcements. This is not an official forecast. If I "run away, run away" (Monty Python), I'll let you know.

No comments: