According to Thomas Churchill, who forecasts on weather in the DR1 Weather & Beyond forum, the overcast skies covering the Dominican Republic are due to large areas of low clouds across the West Atlantic and North Caribbean. The presence of the low clouds and rain is due to a mass of cold air following a strong cold front. The air over the Caribbean is laden with moisture. If cooled, the moisture condenses and clouds and rain are the result. This cold front arrived on the same day as Tropical Storm Odette, but eventually Odette was absorbed by the cold air mass. This cold front is also responsible for causing the weekend blizzards across the eastern United States.
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