St John truly is an island paradise – enjoying tropical temperatures and cooling tradewinds through most of the year. Summer months see a decrease in the tradewinds and increased temperatures ( avg 85.5F). High-season ( Oct – Feb) on St John temperatures average 78F.
Avg. Temperature – St. John
St John Weather info
SPRING ( March > May) 78.7 ~ SUMMER (June > August) 85.5 ~ FALL ( September > November) 81.5 ~ WINTER (December > February) 76.7
High temperatures during the day average 81.5F with nighttime temperatures averaging 72F.
Water Temperatures
The waters surrounding St John average 79F in the winter and 83F in the summer months.
Average Rainfall
The rainiest months in the US Virgin Islands are November, October, September, August and May.
St John receives about 46″ of rain each year. Here are monthly averages: JAN ( 2.65″), FEB ( 2.2″), MAR (2.0″), APR ( 3.78″), MAY ( 4.1″), JUN ( 2.40″), JUL ( 3.30″), AUG ( 4.40″), SEP ( 6.20″), OCT ( 5.10″), NOV ( 6.50″), DEC ( 3.30″)
NOTE: Weather reports will often report “rain” for most of any given week. While you may get some rain – most afternoon rain showers only last 20 – 30 min.
Hurricanes
The greatest weather threat to you and your vacation in the Virgin Islands is probably hurricanes. These rapidly developing and extremely powerful storms produce strong winds, torrential rain and storm swells / flooding. Because the path of a Caribbean hurricane is unpredictable – travelers visiting during hurricane season are advised to take out travel insurance.
Hurricane Season
August and September are the months with historically high numbers of hurricanes in the US Virgin Islands. Hurricanes in July and October are much rarer.