A cold front is expected to cause wet weather across the northeast Caribbean on Wednesday and Thursday in the Leeward Islands and British Virgin Islands.
This is according to a Hydrologic Outlook issued by the Antigua and Barbuda Meteorological Services on Tuesday.
It says there is the potential (10 per cent chance) for rainfall totals across the area to exceed 100 mm or 4 inches in 24 hours during the forecast event.
The report says most models surveyed indicate more than 50 mm (2 inches) of rainfall is likely.
Flash flooding may occur in flash-flood-prone areas because of the heavy rainfall rates and duration of precipitation.
However, given the uncertainty in the extent to which the front will develop and other atmospheric conditions, it is not possible to predict the exact magnitude of the flooding, at this time.
The Met Services notes a hydrologic outlook, which is not a forecast, but a broad assessment, means that a significantly heavy precipitation event may occur that could cause flooding or aggravate existing flooding.
Outlooks are usually issued in the range of 36 to 72 hours in advance of an event.
Several islands have already issued statements alerting the public about possible severe weather.
The British Virgin Islands Department of Disaster Management in a weather alert says as the frontal trough nears the territory, weather conditions will continue to worsen. Showers and isolated thunderstorms are expected later this afternoon into tonight. Rainfall amounts could range between 2 to 4 inches. Potential impacts include flash flooding, urban flooding and hazardous marine conditions for small crafts.
In Anguilla, the Blowing Point Ferry Terminal temporarily ceased operations today due to the inclement weather. A statement from the Anguilla Air and Sea Port Authority says as it stands vessels are experiencing difficulty docking and conditions are expected to further deteriorate as the day progresses. The public was advised that alternative for travel can be sought through the carriers which service the Clayton J Lloyd International Airport.
In Sint Maarten, the Meteorological Department says a small craft advisory is in effect until further notice. The weather forecast states increasing moisture and instability associated with an approaching cold front will cause unsettled weather such as cloudy skies, isolated showers, and elevated winds and seas.
It warns that hazardous sea conditions also associated with this frontal boundary will affect regional waters through the remainder of the week.
In St Kitts and Nevis, the National Emergency Management Agency (NEMA) in a public announcement says a trough system is expected to enter the area on Wednesday through Thursday. It says this trough will cause an increase in instability and is expected to lead to an increase in clouds and showers. Some of the showers could be moderate to heavy at times during the passage of the trough. Over 2 inches of rain is possible during that time.
Meanwhile, the Antigua and Barbuda Meteorological Services says a high surf advisory will go into effect later today for Antigua, Barbuda, Anguilla and the British Virgin Islands. It will go into effect this evening until tomorrow; and may need to be extended through the weekend.
The Met Services says moderate long-period swells are expected to reach the area again and cause hazardous conditions along mainly northern and north-facing coastlines.
These swells could cause life-threatening surfs and rip currents on affected coastlines. A high surf advisory means that dangerous surfs of 2 to 3 metres or 6 to 10 feet will affect some coastlines in the advisory area, producing hazardous conditions.
