ULL question please?

[Guest]

How often do ULL work down to the surface, because I was looking at the LLC in the GOM and just wondering since the ULL in the sw gulf has such a tight spin and moisture.

[Aquawind]

It is a pretty rare event..If you look at the ATL water vapor loops you can see many many ULL at any given time..very few actually become tropical. They do happen but most often as hybrid systems. It just takes along time for a cold core ULL to works it's way down and become a total warm core system..usually they run into one issue or another before it all comes together. Anything more than 2 a year would be weird..imho

[AussieMark]

I was just wondering why the NHC mention the thunderstorm activity in the eastern Gulf of Mexico and not the thunderstorms east of the Bahamas since the latter looks the the better of the two as far as organization goes which is not saying much.

[Frank P]

For what its worth take a look at the vis loop in the area around 27.5 n south of Mobile... looks like a weak low pressure is trying to form at the surface.... bouy data for pressure and wind fields nothing to get excited about though... but it is a lot farther north than I expect for something to spin up from this wave... only late last night most of the convection was off the Yucatan and in the extreme SE GoM... now we've got a weak spin in the north central GoM... strange things these tropical systems... appears to be moving north

[Stormsfury]

I was just wondering why the NHC mention the thunderstorm activity in the eastern Gulf of Mexico and not the thunderstorms east of the Bahamas since the latter looks the the better of the two as far as organization goes which is not saying much.

That area in the Bahamas is a trough carving out in between Fabian and the system now trying to organize in the GOM. Convection is being enhanced by divergent shear from the anticyclone in the Western Caribbean and seen quite well on WV imagery

http://www.ssd.noaa.gov/PS/TROP/DATA/RT ... -loop.html