Dry air caught in the cyclonic circulation of Hurricane Oscar, has been contributing to fair conditions across our area (SVG). Lower level troughs drifting southward from Oscar are affecting the Northern Windward and Leeward Islands (north of St. Lucia) with few scattered showers. Oscar should be moving northward and away from the Lesser Antilles tonight; allowing moisture at the mid levels to gradually
increase as a delayed lower level trough (previously tropical wave) approaches on Tuesday with few showers. By nightfall, continued moisture converging across our islands could result in scattered showers with isolated thunderstorm activity possibly supported by upper level conditions from Wednesday through Friday, as an Atlantic High Pressure System maintains moisture feed towards Oscar.
Wind directions varied this morning and gentle (10 - 20km/h) breeze this afternoon should gradually increase, becoming moderate tonight with north-easterly breeze by early Tuesday. A veer to east south-east Tuesday afternoon is expected with the crossing of the lower level trough/tropical wave. Varying directions can be expected on Wednesday while fresh (up to 40km/h) north-east trades are anticipated by late Thursday.
Mean sea level (MSL) readings across our area should range 1010 – 1012 mb this afternoon, beginning to rise tonight as ‘Oscar’ moves northward. On Wednesday and Thursday, readings could occasionally rise to 1015 mb with two High Pressure cells (western and eastern) in the Atlantic Ocean.
Smooth seas on the west coasts and slight seas on east coast should be rising late by tonight. Expect north north-easterly swells to range between 1.2m and 1.8m on Tuesday, rising in response to increased wind speeds to peak near 1.5m on west and near 2.2m on east coasts by Thursday night with northeasterly swells.
Good visibility on our horizon could be decreased by Tuesday as a patch of dust concentration with varying intensity moves across our area, gradually improving during Thursday
Notes:
At 11:00 am, Hurricane Oscar was near latitude 25.8 North, longitude 58.4 West. Oscar continues to strengthen over the open Atlantic and is moving toward the west-northwest near 7 mph (11 km/h); while a turn toward the northwest at a slower forward speed is expected later today, followed by a motion toward the north tonight. On Tuesday, Oscar is forecast to begin moving toward the north-northeast with an increase in forward speed. The hurricane is then expected to accelerate quickly toward the northeast through the middle of the week.
Tropical wave along 34W/35W from 11N southward with scattered moderate to isolated strong rain-showers from 06N to 10N between 32W and 37W…about 1560 nmiles away
Tropical wave along 52W/53W from 13N southward with Isolated moderate to locally strong rain-showers within 240 nm to the east of the wave, and within 270 nm to the west of the wave.…. about 480 nmiles away… vicinity Tuesday