Let's take a quick look at the latest, 00Z-8PM EDT, RAOB or weather balloon observations from the Eastern Caribbean.

TJSJ-San Juan, P.R.
PRES HGHT TEMP DEWP RH DD WETB DIR SPD
mb m____C___C__%___C__C deg_ knt
850 1543 16.4 14.5 89 1.9 15.1 035 3kt
700 3173 8.2 -2.8 46 11.0 2.7 350 10kt
500 5880 -7.3 -22.3 29 15.0 -11.9 355 11kt

So winds vary from the NNE at 3kt at 5000ft to NNW at 11kt at 18000ft.
Relative Humidity drops from 89% at 5000ft to 29% at 18000ft.

TFFR-Pointe-a-Pitre - Le Raizet, Guadeloupe
850 1542 16.2 12.6 79 3.6 13.8 095 6kt
700 3175 8.2 -3.8 42 12.0 2.3 190 7kt
500 5880 -5.9 -21.9 27 16.0 -11.0 345 6kt

Here we have a good bit of directional shear in place.
5000ft ESE at 6kt.
10000ft SSW at 7 kt
18000ft NNW at 6kt.

Relative Humidity drops from 79% at 5000ft to 27% at 18000ft.
In both of the above cases there is dry air aloft.

The RAOB or weather balloon observations from TTPP-Piarco International Airport, Trinidad, Trinidad and Tobago and TBPB-Grantley Adams, Barbados were from 8AM EDT this morning.

Thanks to tha Unidata Program at UCAR and The College of Dupage for the data.
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