San Juan Hurricanes, Climate and Average Weather

Boqueron beach; © Puerto Rico Tourism Company

By Scott Bateman
Count on San Juan weather to be warm just about any month of the year, but don't count on clear skies for all of those same months.

San Juan is the capital city of the island of Puerto Rico, a U.S. territory in the Caribbean, and also a major port of call for Caribbean cruises.

Many cruise ships leaving from the U.S. coast will stop there as part of an eastern Caribbean cruise.

Other cruises will start from there to reach southern destinations in the Caribbean.

Average Rainfall

San Juan weather in January through March experiences only a modest amount of rainfall like most other locations in the Caribbean.

Unlike other locations, it has a higher than average amount of rain in the spring and early summer months.

Rainfall averages two inches or less from January through March and the climbs to about four inches in April.

It climbs again in May to one of the high points of the year at about six inches. It happens that May is a brief rainy season for many Caribbean destinations.

Total rainfall drops to about four inches in June and July before climbing to five inches or more during the most active Caribbean hurricane months of August through November.

Rainfall drops slightly to about four inches in December.

Rain Days

The average number of days it rains also is low during the early months of the year -- less than 10 days from February through April.

Rain days average about 12 in May and June and then climb to about 14 or 15 from July through the remainder of the year.

Temperatures

San Juan temperatures are less of a factor in planning a trip than the average rainfall each month.

The average high temperature in January, the coldest month of the year, is 83 degrees Fahrenheit.

Temperatures climb until reaching a peak of about 89 degrees in August and September.
The average lows reach about 70 degrees at night in January and February and start to climb from there.

Expect sea water temperature to average about midway between the high and low air temperatures depending on the time of day.

Best Months to Go

The best month of the year to visit San Juan for a combination of warm temperatures, low total rainfall and fewest rain days is June.

Late winter and early spring are good times for low rainfall but slightly cooler temperatures.

The worst months to go for total rainfall are August through November.