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Hourly Forecast
Daylight Hours
05:47
Sunrise
17:46
Sunset
Moon
Waxing Crescent
09:46
Moonrise
21:34
Moonset
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Weather in San Juan today, September 16, 2026
San Juan looks damp on September 16, 2026, so plan for wet spells during the day. Early travel and outdoor time should assume rain can arrive quickly. Early hours look the most unsettled, with rain probability near 68% by 11:00. The thickest cloud arrives around 07:00, reaching about 80%.
The day peaks near 28°C and cools toward 23°C. Expect humidity between 76% and 97%, most humid near 00:00. Airflow remains manageable, reaching about 2.1 km/h around 13:00.
Expect the wet theme to continue later, as rain odds reach 94% near 14:00. Cloud amounts hold near 78% around 23:00. Visibility holds near 15.9 km, though it can fall to 12.4 km. The sun rises at 05:47 and sets at 17:46, for a total of 11 hours 59 minutes of sunlight today.
Taken together, San Juan looks wet enough on September 16, 2026 that flexible outdoor plans work best, with temperatures peaking near 28°C.
Frequently asked questions about weather in San Juan
How warm does it get in San Juan?
The warmest month in San Juan is September, with average high temperatures of 31°C. The average temperature during this period is around 27°C.
How cold does it get in San Juan?
The coldest month in San Juan is July, with average low temperatures of 23°C. The average temperature during this period is around 25°C.
What is the wettest time of year in San Juan?
The wettest month in San Juan is April, with an average of 333mm of precipitation.
What is the driest time of year in San Juan?
The driest month in San Juan is August, with an average of 145mm of precipitation.
