The Western Atlantic High Pressure System is dominant across the island chain, with limited moisture converging on its southern edge in weak pulses. These pulses bring shallow cloud patches with brief showers alternating with dry stable conditions. A trough should be approaching the island chain late Tuesday with limited moisture, but few showers could converge behind the axis during Wednesday and
Thursday as an upper level long-wave trough provides occasional support.
North-easterly fresh (30 - 40km/h) breeze are being pumped by the Western Atlantic High Pressure System, bringing cool air off a trailing cold front across the Atlantic Ocean. Tonight into early Tuesday, higher gusts are possible, nearing moderate gale (50 - 61km/h) strength especially across the Grenadine islands Wednesday night. Direction should be veering during Thursday, bringing some moisture from equatorial regions.
Moderate sea swells with wave heights (1.5 – 2.2m) and originating from east north-east, are across St. Vincent and the Grenadines (SVG) due to increased wind speeds. Advisories are being issued for mariners as wave heights are above normal on both west (Caribbean Sea) and east coasts (Atlantic Ocean) of our islands and gradually rising across SVG. By late Tuesday/early Wednesday, wave heights are expected to range 1.5m to 2.5m on the west coasts and around 1.5m to 2.7m on east coast. A slight reduction is possible during Thursday.
Barometric readings should range 1014 – 1016mb, rising to 1018mb by Wednesday when a low Pressure area with associated cold front should move off the North American coast. The low should cause the High Pressure System to dip south across our area.
A Plume of dust across the Atlantic Ocean is being steered by the Atlantic High Pressure System. Slight haze is approaching the island chain to create hazy conditions later this afternoon, with PM2.5 values expected to peak near 24µg/m3 for and PM10 values nearing 35µg/m3. Patches of dust concentration of varying intensity can be expected from tonight and possibly thinning out late Tuesday….JMCD