ClimateAverages

San Marcos Climate

Texas, United States of America · population 60,684 · 232 weather stations within 200 km · records 1799 to 2025

Average annual daytime high
26.3°C
Warmest month · August
35.2°C
Typical daytime high
Coldest month · January
3.4°C
Typical overnight low

San Marcos has an average annual daytime high of 26.3°C, based on the 1951 to 1980 baseline. Its warmest month is August, when highs typically reach 35.2°C, and its coldest is January, with overnight lows near 3.4°C.

Month by month averages

MonthAvg highAvg low
January16.1°C3.4°CColdest
February18.6°C5.3°C
March22.8°C9.1°C
April26.4°C13.8°C
May29.6°C17.6°C
June33.1°C21.0°C
July35.0°C22.2°C
August35.2°C22.0°CWarmest
September32.2°C19.6°C
October27.6°C13.9°C
November21.4°C8.5°C
December17.7°C4.7°C

Temperature range across the year

1°10°19°28°37°JanFebMarAprMayJunJulAugSepOctNovDec
Daytime high Overnight low
Hottest year on record
2016
+2.0°C vs. 1951–1980
Coldest year on record
1880
-2.0°C vs. 1951–1980

These figures reflect annual averages, not single-day records. Daily observations are outside this dataset's precision.

Is San Marcos getting hotter?

Since 1900, San Marcos's average temperature has risen by +2.0°C. Compared to the earliest station records that begin in 1799, warming totals +2.0°C.

19.3°19.9°20.6°21.2°21.8°1951–1980 baseline190019251950197520002025

20-year smoothed annual temperature reconstructed from station anomalies. Dashed line: 1951–1980 baseline.

Best time to visit
January to December

Daytime highs sit within a comfortable 15°C to 26°C range.

FAQ

What is the average temperature in San Marcos?

San Marcos's average annual daytime high is 26.3°C, based on the 1951 to 1980 baseline period. The warmest month is August, with highs averaging 35.2°C, and the coldest is January, with lows averaging 3.4°C.

What is the warmest month in San Marcos?

August is the warmest month in San Marcos, with typical daytime highs of 35.2°C.

What is the hottest year on record for San Marcos?

2016 is the hottest year on record for San Marcos, running +2.0°C above the 1951 to 1980 baseline.

Is San Marcos getting hotter?

Yes. Since 1900, San Marcos has warmed by roughly +2.0°C.

When is the best time to visit San Marcos?

January to December typically offers the most comfortable daytime highs, in the 15°C to 26°C range.

Nearby cities

Baseline period 1951 to 1980. Monthly averages are the mean of station observations weighted by proximity. Warming trend is the 20-year smoothed anomaly against that baseline.