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Hourly Forecast
Daylight Hours
07:21
Sunrise
19:31
Sunset
Moon
Waxing Crescent
11:42
Moonrise
21:33
Moonset
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Weather in San Marcos tomorrow, September 16, 2026
San Marcos stays under cloudy skies on September 16, 2026, with only brief brighter breaks. Plan for a day that feels grey more often than open. Cloud leads the morning, peaking close to 65% near 02:00. Sunshine has little room until later in the day.
Expect highs of 36°C and cooler readings close to 25°C. The air stays humid, with relative humidity between 43% and 94% and the peak around 07:00. Expect gentle winds, highest near 10:00 at 3.3 km/h.
Expect persistent cloud later on, with amounts around 61% by 17:00. Sunshine remains the exception, not the rule. Visibility stays generally good near 14.5 km on average, though it can drop toward 12.7 km in thicker cloud or showers. Daylight runs from 07:21 to 19:30, lasting 12 hours 8 minutes of sunlight today.
The practical takeaway for San Marcos on September 16, 2026 is a cloudy day that stays usable, just not particularly bright, around 36°C.
Frequently asked questions about weather in San Marcos
How warm does it get in San Marcos?
The warmest month in San Marcos is August, with average high temperatures of 36°C. The average temperature during this period is around 30°C.
How cold does it get in San Marcos?
The coldest month in San Marcos is January, with average low temperatures of 6°C. The average temperature during this period is around 11°C.
What is the wettest time of year in San Marcos?
The wettest month in San Marcos is May, with an average of 131mm of precipitation.
What is the driest time of year in San Marcos?
The driest month in San Marcos is February, with an average of 51mm of precipitation.
