According to Dr Jeff Masters‘ Weather Underground blog, “with dry air expected to be in the Caribbean, the moderate levels of wind shear would likely be able to drive the dry air into the circulation of 96L, keeping any development slow“.

This Afternoon’s Forecast Valid From 1600Z Wednesday 2014-08-20 To 2200Z Wednesday 2014-08-20

Synopsis: A tropical wave is approaching the island.

Wx : Partly cloudy to cloudy at times with a few scattered showers.

Winds: E – ENE at 15 – 35km/h.

Seas: Slight to moderate in open water swells 1.0 to 1.5m.

Tonight’s Forecast Valid From 2200Z Wednesday 2014-08-20 To 1000Z Thursday 2014-08-21

Synopsis: A tropical wave will be affecting the island.

Wx : Partly cloudy to cloudy with a few scattered showers.

Winds: ENE – E at 15 – 35km/h.

Seas: Slight to moderate in open water swells 1.0 to 1.5m

For the North Atlantic…Caribbean Sea and the Gulf of Mexico:

Shower and thunderstorm activity associated with an elongated area of low pressure located several hundred miles east of the Windward Islands has become a little better organized during the past few hours. Additional slow development of this system is possible during the next day or two, and a tropical depression could form as the system moves west-northwestward at 10 to 15 mph across the Lesser Antilles and into the Caribbean Sea. After that time, land interaction could limit development potential over the weekend.

Regardless of tropical cyclone formation, gusty winds and heavy rainfall are possible across portions of the Lesser Antilles, Puerto Rico, and the Virgin Islands on Thursday night and Friday. Interests in those islands should closely monitor the progress of this system.

An Air Force Reserve Hurricane Hunter aircraft is scheduled to investigate this system tomorrow afternoon, if necessary.

* Formation chance through 48 hours…medium…50 percent.
* Formation chance through 5 days…high…60 percent.

$$
Forecaster Brennan