San Juan weather by month

Warmest month

August

33°C average high

Coolest month

February

18°C average low

Wettest month

March

82 mm of rain

Driest month

July

22 mm of rain

Average temperature and rainfall in San Juan by month

Averages of the daily highs and lows recorded in each month, with total rainfall, mean humidity and mean wind speed.

Month	Avg high	Avg low	Record low / high	Rainfall	Humidity	Wind
January	28°C	18°C	11°C / 34°C	52 mm	82%	9 km/h
February	28°C	18°C	10°C / 34°C	47 mm	79%	10 km/h
March	30°C	19°C	14°C / 33°C	82 mm	77%	11 km/h
April	30°C	20°C	15°C / 34°C	72 mm	77%	11 km/h
May	31°C	21°C	14°C / 35°C	60 mm	78%	12 km/h
June	32°C	21°C	14°C / 36°C	29 mm	76%	13 km/h
July	33°C	23°C	18°C / 38°C	22 mm	75%	14 km/h
August	33°C	23°C	18°C / 50°C	37 mm	77%	13 km/h
September	33°C	23°C	14°C / 37°C	43 mm	80%	10 km/h
October	31°C	22°C	16°C / 36°C	60 mm	81%	9 km/h
November	30°C	21°C	16°C / 32°C	58 mm	86%	8 km/h
December	28°C	19°C	14°C / 32°C	45 mm	84%	9 km/h

Frost and snow-likely months in San Juan

No month in San Juan averages a night of 2°C or below. The coldest month is February with an average low of 18°C and a record low of 10°C, so frost is rare and snow is very unlikely.

These records carry temperature and precipitation, not snowfall totals.

Best time to visit San Juan

The most comfortable time to visit San Juan is generally December to February, balancing mild daytime temperatures against the driest stretch of the year. Temperatures stay fairly even all year and rain concentrates around March, totalling about 606 mm a year.

Travellers who prefer heat should aim for August, when highs average 33°C. March is the month to avoid if rain would spoil your plans — it averages 82 mm, roughly 4× the rainfall of the driest month (July).

San Juan climate: your questions

Does it snow a lot in San Juan?

No: the coldest month in San Juan is February with an average low of 18°C and a record low of 10°C, so snow is very unlikely. What is falling now: San Juan weather today.

Which months are best for visiting San Juan?

December to February are the most comfortable months in San Juan, with highs near 28°C. August is the warmest month, averaging 33°C by day; March is the wettest, with 82 mm; and February is the coolest, with lows near 18°C. What it is doing today: San Juan weather today.

Source: OpenWeather historical and statistical weather data. Values are long-term averages, not a forecast — see the San Juan forecast for what is happening now.