Weather Outlook 18th April 2019 (12 noon)
A weak shearline feature is across the Windward Islands and marginal increase in moisture at mid-levels could result in scattered showers across our area this afternoon into tonight. A few scattered showers can be expected on Friday due to shallow cloud patches within the trade wind-flow.
Moderate (20 - 35km/h) east north-easterly trades are across our islands and should gradually increase to fresh (up to 40km/h) breeze by tonight with occasional strong gusts.
East north-easterly sea-swells between 0.6m and 1.2m are on the west coasts, while east coasts can expect sea-swells between 1.2 and 2.0m. A gradual rise in wave heights is expected from tonight with increased wind speeds; this may trigger an advisory caution for Mariners by late Friday.
Two High Pressure cells are anchored on west and east sides of the Atlantic Ocean, but the western cell is expected to gain dominance by Saturday. The Leeward and northern Windward Islands should then be under the influence of the Western Atlantic High Pressure System, but a deep ‘cut-off low’ pressure area is expected to develop in the Central Atlantic creating instability across the island chain. This ‘cut-off low’ feature, could create favourable mid to upper level (tropical upper tropospheric trough-TUTT) support for shower activity across the southern most islands this weekend. Lower-level troughs propagating across the islands, including St. Vincent and the Grenadines (SVG) could cause a spike in shower activity between Saturday evening and early Sunday.
Barometric readings should range between 1013mb and 1016mb across our area, with some fluctuations (1012 - 1017mb) over the weekend.
Occasionally, slight haze may be noticeable across our area due to a thin film of dust concentrations which should be cleared by Friday.