See exactly when rain will start and stop with a minute-by-minute precipitation nowcast for the next hour.
28°
Mostly Cloudy
Feels Like: 30°
Min: 27°
Max: 29°
The next few hours will be mostly cloudy, with tomorrow reaching 31°C and dropping to 28°C. The coming days will be light rain throughout the day.
Compare today's weather with yesterday's data and track temperature trends over time.
Hourly Forecast
Daylight Hours
06:58
Sunrise
18:58
Sunset
Moon
Waxing Gibbous
14:55
Moonrise
01:21
Moonset
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View stargazing scoreWeather in Saint-Louis tomorrow, September 21, 2026
Cloud cover dominates in Saint-Louis on September 21, 2026, keeping sunshine limited. Expect a grey, overcast feel rather than long bright spells. The first half of the day looks overcast, as cloud amounts reach about 93% around 00:00. Brighter weather, if it comes, waits until later.
Temperatures climb from an overnight low near 27°C toward a daytime high of about 31°C. Moisture in the air spans 65%-88%, with the highest values around 00:00. Winds stay light, near 4.6 km/h by 17:00, so the day feels still more than breezy.
Expect persistent cloud later on, with amounts around 91% by 12:00. Sunshine remains the exception, not the rule. Expect visibility around 16.1 km. Daylight runs from 06:58 to 18:58, lasting 11 hours 59 minutes of sunlight today.
Taken together, overcast skies in Saint-Louis on September 21, 2026 favour indoor or covered options, with temperatures near 31°C.
Frequently asked questions about weather in Saint-Louis
How warm does it get in Saint-Louis?
The warmest month in Saint-Louis is October, with average high temperatures of 31°C. The average temperature during this period is around 28°C.
How cold does it get in Saint-Louis?
The coldest month in Saint-Louis is March, with average low temperatures of 19°C. The average temperature during this period is around 22°C.
What is the wettest time of year in Saint-Louis?
The wettest month in Saint-Louis is August, with an average of 64mm of precipitation.
What is the driest time of year in Saint-Louis?
The driest month in Saint-Louis is January, with an average of 0mm of precipitation.
