Caribbean: Few showers are moving from SE towards Saint Lucia, a few showers are east of Tobago and light rain is over parts of Dominica and Martinique. Expect increasing chances for occasional showers, some locally heavy and slower moving during the afternoon to early evening.
Should start to see lesser chances in the night in Windwards… Leewards(especially St. Kitts/Nevis) and Virgin Islands remain under best conditions for convergence of high moisture leading to heavy showers and thunderstorms. Less moisture convergence and upper divergence is over Windwards today but high moisture is available with slow to modest(5-15mph) steering winds so localized heavy showers are a possibility after daytime heating.
There is still uncertainty with timing and location of the individual more heavier showers in Windwards, but with a southeast to southerly low to mid-level steering wind. Over Trinidad under an easterly flow showers and possible thunderstorms form more on the west.
There is a new surge of moisture ahead of an surface trough and broad area of elongated spin which is just offshore of Suriname and French Guiana. This feature looks a bit better organized than yesterday and has some moderate to few strong thunderstorms in bands on west to north sides.
There are ENE/NE winds coming into Venezuela, south winds coming over French Guiana/Suriname… and some hints of low level clouds moving from SW over Guyana. The GFS has show this area being part of a broad area of moisture with the tropical wave behind it to start a period of wet weather from late Tuesday. In Trinidad, this may start during the day Tuesday.
Heavy rainfall periods were experienced in the Leewards and Virgin Islands. There were also localized heavy showers in the mountains of Guadeloupe. A few brief light to heavy showers impacted Martinique, Saint Lucia and Tobago. Recently moderate to heavy showers are affecting St Vincent and some Grenadines. A trough with high moisture convergence is extended across the northern islands and will continue to bring some more heavy rainfall periods overnight.
The central Windwards from St Vincent, Saint Lucia, Barbados to Dominica will receive a bit more drier air overnight to Tuesday, except in the south where moisture from ITCZ ahead of a broad area of spin and tropical wave will bring occasional light to heavy showers in Trinidad and Tobago, Grenadines and Grenada.
The broad area of showers and thunderstorms with the tropical wave and elongated area of spin is north of Guyana, Suriname and French Guiana. Due to the system pulling on air towards it, the seabreeze thunderstorms with heavy showers formed along the coast where most people live. There will be some more chances for these next 2 days in coastal Guianas.