Sunday, July 31, 2011

Atlantic Blobette: July 31, Update A

That blobette I mentioned a few days ago has put on a nicer frock now (maybe in the casual summer dress range, not quite yet an evening gown ;-)).

However it is still somewhat disorganized, and it is spread out over a broad area with some pretty decent circulation in the lower parts of the troposphere, centered around 13-14N, 51-53W, and some circulation in the upper half of the troposphere, centered around 13-14N, 48-49W. The wind shear is also skewed, with more to the north of the system than to the south.

It has been trying to get the convection we need, but that’s still a little scattered as well with more on the western side than the eastern. This is partly because the western is now over ocean waters that are warmer than 26 deg C over the upper 100m of the water column, whereas on the eastern side they are warm only over the upper ~50m. As it moves WNW (at 15mph), it will eventually be over the deeper warmer water region and we should see convection pick up.

They are sending in a plane to investigate this afternoon and they have the ‘chance of it becoming a tropical cyclone’ (note: lower case J) at ‘near 100%’ (not quite sure why they bother with this level!), so I am expecting to have a Tropical Depression or a Tropical Storm by the end of the day.

Given the broad area this is spread over, and more importantly, given that there is circulation in the upper troposphere, *if* this system gets its act together before reaching the Windward Islands, I think there is a good chance this could be our first hurricane of the season.

I’ll pop back with an update once this one puts some make-up on. ;-)

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: