San Antonio averages 97 days a year above 90°F, with May the wettest month at 4.38 in of normal rain. The hottest day on record was 110°F on Sep 6, 2000; the coldest, 9°F on Feb 16, 2021. The single biggest 24-hour rain event recorded was 14.33 in on Oct 18, 1998.
Climate and Average Weather Year Round in San Antonio
Year-round temperature
In San Antonio, the warmest months are June through September, with average daily highs between 90°F and 95°F. The coldest stretch runs December through February, with highs between 63°F and 68°F and overnight lows reaching 40°F.
Rainfall through the year
Rainfall in San Antonio averages 2.8 in per month over the long run. May is the wettest at 4.4 in, while February is the driest at 1.9 in.
Days at 90 °F or hotter
San Antonio averages 97.0 days per year at 90 °F or hotter. The hottest year on record saw 153 such days (2011); the coolest just 6 (2014).