Friday, August 15, 2008

The Blobette: August 15 Update A

This "no_tropical_cyclone_not_even_a_Tropical_Depression" system is
beating the heck out of the Virgin Islands and Puerto Rico at the moment
with some strong convection, and is heading for Hispaniola. The convection
is massive - usually the sort of cloud tops seen with a decent hurricane,
but there is no eye. I read that the reason why they didn't call it a TD
yesterday was because although the plane was showing TD/TS level winds, it
couldn't find an area of closed circulation at the surface... and the
sparse data they have now also doesn't show closed circulation,apparently.
*That* is what they are waiting to find. From where I am sitting, it looks
closed to me, and not only that, but it looks like it's now in the entire
lower troposphere and extending upwards... but I don't have the very fine
information that they have at their fingertips. Satellite winds now show
some areas with tropical storm winds (TS range:39-73 mph).

For those of you who know this jargon: there's good low level convergence
and high level divergence now as well. I will have to explain it to
everyone else at a later date... (apologies).

It's so odd... usually the NHC errs on the side of caution, but in this
case it's like there's been a switch in policy or something. Anyway, when
you emerge from this on St. Thomas, send me a note and let me know how you
fared this night.

Now, the track is, as I thought yesterday looks like it will be a little
farther south than they had... which means it will interact a bit more
directly with Haiti/DR and although PR is having very little effect on
this blobette, one can hope that the mountains ahead of the system will do
something. There is also a region of slightly higher windshear on the
western side of Hispaniola, and maybe that will also help.

I'll try and send another update out later today.
Gotta run...

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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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