|Barbados Meteorological Services
Initial to 4 days discussion based on Satellite imagery,BMS Radar composite,S.P.I.E products,GEM, GFS, WW3, UKMET and BMS WRF modeling, surface and upper air observations, Satellite derived products.
DATE: 20170301 PERIOD: Morning
The surface to low level Atlantic high pressure remained the dominant feature across Barbados and the Eastern Caribbean overnight. Although a mid level shearline (east/west trough) provided some weak instability across the chain, only shallow brief convection was recorded across Barbados and most of the other Eastern Caribbean islands. The exception was in the vicinity of the Grenadines and Trinidad and Tobago where a weak low pulse in combination with the mid level trough, generated some scattered showers early in the night.
Further south, satellite imagery revealed deep convective activity across French Guiana and most of Surinam. This activity was as a result of a low level trough, coupled with ITCZ activity and a diffluent pattern aloft. While cloudy to overcast skies and light to moderate rain was recorded across French Guiana throughout the night, partly cloudy to cloudy skies and some scattered showers were observed across Surinam. Guyana remained under fair to partly cloudy skies.
Moderate to brisk easterly to east northeasterly breezes generally ranging from 12 to 25 knots, along with some higher gusts, were reported across the region overnight. seas were moderate to rough with swells peaking at 3.0m.
A surface to mid level ridge pattern was the dominant feature across the central Caribbean islands. Low level cloud patches moving in and out of these islands spread only brief shallow convection. On the other hand, a pre-frontal trough maintained cloudy skies and a few scattered showers over the northern Bahamas.
Eastern Caribbean Outlook
The surface to low level Atlantic high pressure system will continue to make its presence felt across Barbados and the Eastern Caribbean over the next four days, The mid level portion of the ridge will fluctuate in strength as the above-mentioned mid level shearline oscillate across the chain. This trough will continue to provide some enhancement for shallow low level cloud patches moving across the islands. Hence the pattern of brief spotty off and on showers will continue today. By Thursday, moisture associated with a westward moving low level trough will be confined to the republic of Trinidad and Tobago by the strengthening low level ridge pattern. It will be around this time that some thunderstorm activity is likely over these islands (Trinidad and Tobago). As the weekend approaches and the mid level trough is pushed northwards by an expanding equatorial ridge, a developing low level shearline will induce moisture across Barbados and the other southern islands. Showers will persist into Saturday when a few isolated thunderstorms are likely.
Meanwhile easterly to east northeasterly strong 20 to 25 knots breezes across the region, will sustain rough seas of 2.5 to 3.5m from tonight thru to Saturday,
Western Caribbean Outlook
Later today, debris clouds associated with the pre-frontal trough system will gradually dissipate, as the low to mid level ridge pattern completely dominates the weather across this area. A more subsident pattern across these islands will inhibit significant cloud development and deep shower activity. Hence showers, if any, are expected to be brief and shallow. By Thursday another frontal system will move off the eastern United States seaboard. The tail-end of this system will move across the northern Bahamas on Friday.
|Meteorologist Rosalind Blenman|