Which is winning the enviromental battle dry or moist air?

[cycloneye]

Convection has diminished tonight as the battle between the dry air and the moist one is raging on and it looks like the dry air is prevailing so far.Although the structure is looking good on sat pics the lack of deep convection will not make the NHC classify it into a TD.Remember the John Hope's rule about systems forming before it reaches the islands.If it not form before it reaches the islands it will have to wait until it gets into the western caribbean.Unless it refires later tonight convection I dont see this developing east of the islands but when it gets into the western caribbean it may be another story.

[Stormsfury]

Yep, Luis ...the old TZOD "Tropical Zone of Death" ...
But with 2003, nothing will surprise me this year ... the system still is holding some convection near the suspected center of the spin and may be slowing a bit ... but also looks like it's moving due west as well.

One of the oddities I see right now is that there's no appreciable shear in the Eastern Caribbean just ahead of the system ... which in itself, is a little odd ...

SF

[Ola]

Not so fast!!
Look at the moist air hauling and trying to overrunn it from the east

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

[ColdFront77]

I suppose I've heard the late John Hope stating this "rule." I wish I could vividly remember him saying it.

I can see the dry air eroding to the west of this system, east of the Windward Islands. It is looking interesting, despite its appearance earlier today.