San Bernardino weather by month
What a typical year looks like in San Bernardino, California: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Riverside Municipal Airport, 25 km from San Bernardino; records cover 1998–2026.
The year at a glance
- Precipitation a year
- 9.4 in238 mm
- Snow a year
- Rare
- Last spring freeze
- Feb 10
- First fall freeze
- Dec 8
- Heating degree days
- 1,387
- Cooling degree days
- 1,854
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are 33°1° (heating, 99%) and 105°41° (cooling, 1%).
Month by month
San Bernardino in January
Highs average 68°20° and lows 44°6°, with 2.3 in58 mm of precipitation in a typical January.
- Record high
- 101°38° (2003)
- Record low
- 24°−4° (2007)
- Heating degree days
- 296
- Cooling degree days
- 6
San Bernardino in February
Highs average 68°20° and lows 45°7°, with 2.4 in61 mm of precipitation in a typical February.
- Record high
- 93°34° (2026)
- Record low
- 30°−1° (2002)
- Heating degree days
- 251
- Cooling degree days
- 7
San Bernardino in March
Highs average 72°22° and lows 47°8°, with 1.2 in31 mm of precipitation in a typical March.
- Record high
- 102°39° (2026)
- Record low
- 30°−1° (2002)
- Heating degree days
- 189
- Cooling degree days
- 18
San Bernardino in April
Highs average 76°24° and lows 50°10°, with 0.59 in15 mm of precipitation in a typical April.
- Record high
- 102°39° (2004)
- Record low
- 32°0° (1999)
- Heating degree days
- 110
- Cooling degree days
- 48
San Bernardino in May
Highs average 80°27° and lows 55°13°, with 0.2 in5.1 mm of precipitation in a typical May.
- Record high
- 105°41° (2003)
- Record low
- 39°4° (2003)
- Heating degree days
- 33
- Cooling degree days
- 114
San Bernardino in June
Highs average 87°30° and lows 59°15°, with 0.01 in0.3 mm of precipitation in a typical June.
- Record high
- 114°46° (2016)
- Record low
- 43°6° (1999)
- Heating degree days
- 2
- Cooling degree days
- 242
San Bernardino in July
Highs average 93°34° and lows 64°18°, with 0.12 in3 mm of precipitation in a typical July.
- Record high
- 118°48° (2018)
- Record low
- 52°11° (1999)
- Heating degree days
- 0
- Cooling degree days
- 422
San Bernardino in August
Highs average 95°35° and lows 65°18°, with 0.02 in0.5 mm of precipitation in a typical August.
- Record high
- 112°44° (2017)
- Record low
- 53°12° (1999)
- Heating degree days
- 0
- Cooling degree days
- 459
San Bernardino in September
Highs average 91°33° and lows 62°17°, with 0.11 in2.8 mm of precipitation in a typical September.
- Record high
- 117°47° (2020)
- Record low
- 49°9° (2005)
- Heating degree days
- 2
- Cooling degree days
- 349
San Bernardino in OctoberThis month
Highs average 83°28° and lows 55°13°, with 0.33 in8.4 mm of precipitation in a typical October.
- Record high
- 107°42° (2012)
- Record low
- 41°5° (2006)
- Heating degree days
- 31
- Cooling degree days
- 154
San Bernardino in November
Highs average 75°24° and lows 47°9°, with 0.57 in14 mm of precipitation in a typical November.
- Record high
- 100°38° (2010)
- Record low
- 27°−3° (2004)
- Heating degree days
- 155
- Cooling degree days
- 33
San Bernardino in December
Highs average 67°19° and lows 43°6°, with 1.5 in38 mm of precipitation in a typical December.
- Record high
- 89°32° (2021)
- Record low
- 25°−4° (1998)
- Heating degree days
- 318
- Cooling degree days
- 2