A surface to mid level shearline which is oriented NW-SE through the Windward Islands is expected to cross the chain overnight. Residents and motorists should be alert near rivers, streams and low lying areas as associated moisture and unstable conditions could dip south-westward across St.Vincent and the Grenadines overnight
with a general reduction in moisture levels should be noticeable across mainland and northern most Grenadine islands by Thursday afternoon. As the shearline is expected to linger across the Grenadines towards early Thursday morning, scattered showers can be expected mainly across the southern Grenadines during Thursday. (see image at 5:30pm below compliments RAMMB)
A mid level trough should approach the region on Friday (relatively dry and stable), with a narrow shearline possibly developing just north of mainland St.Vincent by evening with scattered showers. By Saturday, upper level conditions could support few scattered showers.
Moderate to fresh (20 - 40km/h) easterly trades can be expected overnight becoming moderate by Thursday. Wind direction should be veering to east south east by Friday afternoon with the Grenadines expecting mainly fresh breeze Friday night.
Barometric Pressure should range 1014 mb - 1014 mb, dipping slightly on Friday to range 1013 mb - 1015 mb.
Expect slight to moderate seas with Easterly swells peaking near 1.2m on west coasts and near 1.8m on east coasts; with slight fall (peak 1.5m) on the east coasts by Friday afternoon.
Note: A tropical wave is forecast to emerge off the west coast of Africa by late Thursday, and then move westward at for the next several days. Environmental conditions are expected to gradually become more conducive for some development next week….will be monitored.