See exactly when rain will start and stop with a minute-by-minute precipitation nowcast for the next hour.
18°
Overcast
Feels Like: 17°
Min: 18°
Max: 19°
The next few hours will be overcast, with today reaching 19°C and dropping to 18°C. The coming days will be breezy in the evening.
Compare today's weather with yesterday's data and track temperature trends over time.
Hourly Forecast
Daylight Hours
05:56
Sunrise
17:52
Sunset
Moon
Waxing Crescent
09:31
Moonrise
22:04
Moonset
Daily Forecast
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Humidity
Weather in San Juan today, September 16, 2026
San Juan looks cloudy on September 16, 2026, with grey skies for much of the day. Sunshine stays limited, so the overall tone is muted from the morning onward. The first half of the day looks overcast, as cloud amounts reach about 91% around 04:00. Brighter weather, if it comes, waits until later.
The temperature range runs from about 18°C up to 19°C. Relative humidity sits between 83% and 90%, reaching its peak around 13:00. Expect gentle winds, highest near 16:00 at 5.2 km/h.
Expect persistent cloud later on, with amounts around 81% by 19:00. Sunshine remains the exception, not the rule. Expect visibility around 16.1 km. Expect sunrise at 05:56, sunset at 17:52, and 11 hours 56 minutes of sunlight today overall.
Overall, San Juan on September 16, 2026 stays grey and muted, so outdoor plans may want a flexible backup even with a high near 19°C.
Frequently asked questions about weather in San Juan
How warm does it get in San Juan?
The warmest month in San Juan is February, with average high temperatures of 25°C. The average temperature during this period is around 22°C.
How cold does it get in San Juan?
The coldest month in San Juan is August, with average low temperatures of 13°C. The average temperature during this period is around 15°C.
What is the wettest time of year in San Juan?
The wettest month in San Juan is February, with an average of 12mm of precipitation.
What is the driest time of year in San Juan?
The driest month in San Juan is November, with an average of 2mm of precipitation.
