Pomona averages 96.6 days a year above 90°F, with February the wettest month at 2.68 in of normal rain. The hottest day on record was 121°F on Sep 6, 2020; the coldest, 20°F on Jan 14, 2007. The single biggest 24-hour rain event recorded was 3.46 in on Feb 5, 2024.
Climate and Average Weather Year Round in Pomona
Year-round temperature
In Pomona, the warmest months are June through September, with average daily highs between 88°F and 96°F. The coldest stretch runs December through February, with highs between 69°F and 70°F and overnight lows reaching 40°F.
Rainfall through the year
Rainfall in Pomona averages 0.8 in per month over the long run. February is the wettest at 2.7 in, while August is the driest at 0.0 in.
Days at 90 °F or hotter
Pomona averages 96.6 days per year at 90 °F or hotter. The hottest year on record saw 138 such days (2020); the coolest just 16 (2026).
Precipitation this year
As of May 28, Pomona has received 5.4 in of precipitation this year — 22% below the long-term normal for this point in the year (7.0 in).