Thursday, August 25, 2011

Hurricane Irene and TD10: August 25, Update B

Quick lunchtime update on things.

Hurricane Irene:
Officially her winds are 115mph, central pressure 951mb. She’s at around 26N, 76.8W moving NNW at 13mph.

Although officially she is still a cat 3 with winds at 115mph, I don’t think she’s a cat 3 (range: 111mph- 130mph). In fact, I think she’s weakened further since this morning and may be a strong cat 1 (range: 74-95mph), possibly weak cat 2 (96-110mph). Here is the satellite IR image of Irene:


There is no eye and there hasn’t been for many hours. She is not very circular – a result of wind shear. And her convection is much weaker – very few really strong thunderstorms (not much of the red or dark gray colour means that the cloud tops are warmer – I covered that in an earlier post this season). She still has a good circulation of course, and also covers a large area, but that doesn’t make her a cat 3.

She’s moving NNW at the moment, parallel to the FL coast. Now it depends if she continues to turn to the North and then NNE soon enough… that will be tomorrow and that’s what I’ll be watching for then.  The latest pressure fields still have a gap in that Georgia/S. Carolina area, but it has shifted north a smidgen. It looks like a South or North Carolina landfall is likely so I would kinda agree now with part of the NHC forecast. In my mind I question her intensity. Currently the forecast has her as a cat 3 all the way up to landfall in North Carolina on Saturday.

I guess they are keeping her as a weak cat 3 so that everyone continues to get prepared for the worst, in case she strengthens further. However, this messes up the science because the data scientists use to study storms are things like the official wind speed, the duration that a storm was at a certain category etc. Surely it would be better to have her downgraded and tell everyone that there’s a strong chance she will become stronger (and why). Ho hum.

Tropical Depression 10:
This poor little thing is struggling to get it’s convection up to speed, it really is. The circulation looks a bit wishy-washy too at the moment. This might not even develop any further if it slows down. I’ll keep watching it of course. Central pressure is 1010mb, which is quite high for a low (!!!), with winds estimated to be 35mph (doesn’t look that strong to me).  It’s officially at 13.3N, 31.8W, moving WNW at 12mph.

Until later,
J.

Blogs archived at http://jyotikastorms.blogspot.com/
Twitter @JyovianStorm

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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.
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