In January, San Marcos typically sees daytime highs of 16.1°C and overnight lows around 3.4°C. Compared to the annual average high of 26.3°C, January runs -10.2°C.
January in San Marcos averages a daytime high of 16.1°C and an overnight low of 3.4°C.
January runs -10.2°C compared to San Marcos's annual average high of 26.3°C, ranking #12 of 12 months by warmth.
Plan for daytime highs near 16.1°C and cooler evenings around 3.4°C.