See exactly when rain will start and stop with a minute-by-minute precipitation nowcast for the next hour.
19°
Overcast
Feels Like: 17°
Min: 18°
Max: 25°
The next few hours will be overcast, with today reaching 25°C and dropping to 17°C. The coming days will be mostly cloudy
Compare today's weather with yesterday's data and track temperature trends over time.
Hourly Forecast
Daylight Hours
06:37
Sunrise
18:48
Sunset
Moon
Waxing Crescent
11:10
Moonrise
20:44
Moonset
Daily Forecast
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Weather in San Marcos today, September 15, 2026
San Marcos stays under cloudy skies on September 15, 2026, with only brief brighter breaks. Plan for a day that feels grey more often than open. The first half of the day looks overcast, as cloud amounts reach about 100% around 06:00. Brighter weather, if it comes, waits until later.
Expect highs of 25°C and cooler readings close to 18°C. Expect humidity between 58% and 94%, most humid near 22:00. Airflow remains manageable, reaching about 5.5 km/h around 14:00.
Afternoon skies stay clogged, peaking close to 100% near 19:00. The grey theme continues rather than clearing out. Visibility holds near 15.9 km, though it can fall to 13.8 km. The sun rises at 06:37 and sets at 18:48, for a total of 12 hours 11 minutes of sunlight today.
In short, cloud leads the story in San Marcos on September 15, 2026; expect limited sun and a peak around 25°C.
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