Grace to Usher Beneficial Rain Into Drought-Stricken Northern Caribbean Islands

By Andy Mussoline, Meteorologist

September 8,2015; 11:19PM,EDT

 

 

Grace will arrive as a tropical rainstorm in the northeastern Caribbean late this week and weekend, bringing rounds of downpours that will be largely beneficial to the region.
A batch of downpours and gusty thunderstorms is set to arrive into the Leeward Islands Thursday night and continue through Friday. Antigua, Barbuda, Guadeloupe and Dominica will be among the first island nations impacted by the rain.

Dominica is still recovering from devastating impacts from Tropical Storm Erika late in August. However, the flood threat with Tropical Rainstorm Grace will be more isolated and less severe.
While the flood threat will need to be monitored, there can be a beneficial aspect to the rain.
"A weakened tropical system without flooding rain or damaging winds would be beneficial to the parts of the Caribbean that are still in the midst of a drought," AccuWeather Senior Meteorologist Krissy Pydynowski said.
Persistent dry, dusty air and lack of rainfall during the early part of the Atlantic hurricane season deepened a historic drought across the northeast Caribbean.
"There have been huge deficits in the rainfall during this wet season [which runs June-November] across the northeast Caribbean," said Senior Meteorologist Bernie Rayno.
From June 1 through Sept. 8, St. Thomas in the Virgin Islands recorded only 32 percent of normal rainfall. St. Croix, also located in the Virgin Islands, recorded only 46 percent of normal. Farther west, San Juan, Puerto Rico, recorded just 60 percent of normal rainfall.

"Moisture from this system will bring Puerto Rico and the Virgin Islands enhanced showers and perhaps a few thunderstorms later Friday into Saturday," AccuWeather Senior Meteorologist and Hurricane Expert Dan Kottlowski said. "...[Some rain] will eventually move into Hispaniola Saturday night and Sunday."
There will be some limits to the benefits of the rain as some of it will be heavy and will prompt flash flooding in the region. Flooding can develop in a matter of minutes, especially over the mountainous terrain.
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The heavy rain can lead to isolated mudslides and washed out roadways. Residents and travelers to the region should seek lower ground if possible when the rain crosses the region. Those who encounter water-covered roadways should turn around and find an alternate route.
Air travel to the region may experience minor delays, but widespread cancellations are unlikely.
Heavy rain will be the primary threat to the region. There can be some gusty winds in heavier downpours, but winds should not be damaging.

Wind shear will continue to persist over Grace as it moves across the northeastern Caribbean. While it will bring enhanced rainfall and some gusty winds to the region, there is little chance the rainstorm can re-strengthen over the region.
Watching for Tropical Development Near Bermuda
Meanwhile, an area of rain and thunderstorms east of Bermuda is being monitored for possible tropical development this week.
"There is a window of opportunity for tropical development through Friday," Kottlowski said.
Satellite imagery of the area being monitored for tropical development east of Bermuda. Red and orange colors represent areas of heavier rain and thunderstorms.
The system will start to move due north later this week. Regardless of development, AccuWeather meteorologists believe the feature will remain away from land.