March in San Marcos averages a daily high of 23.2°C with nights around 10°C. Expect roughly 8 wet days totalling 65mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit San Marcos is February–April.
Based on SAN MARCOS, TX US (0.8km), 1995–2024. 29 years of March data.