San Bernardino, CA climate
San Bernardino has warm winters and hot summers, with very little rain. A typical July afternoon reaches 96°, a January night drops to 42°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in San Bernardino feels like
Winter
Spring
Summer
Fall
San Bernardino weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 67° | 42° | 2.9" | 0 | 7 | 0 | 50° – 61° |
| February | 68° | 43° | 3.5" | 0 | 8 | 0 | 48° – 65° |
| March | 72° | 45° | 2.0" | 0 | 6 | 0 | 51° – 66° |
| April | 77° | 48° | 0.9" | 0 | 4 | 0 | 56° – 66° |
| May | 81° | 53° | 0.3" | 0 | 3 | 0 | 60° – 74° |
| June | 89° | 58° | 0.1" | 0 | 1 | 0 | 68° – 79° |
| July | 96° | 63° | 0.1" | 0 | 1 | 0 | 75° – 84° |
| August | 97° | 64° | 0.1" | 0 | 1 | 0 | 77° – 84° |
| September | 92° | 60° | 0.1" | 0 | 1 | 0 | 73° – 80° |
| October | 83° | 53° | 0.5" | 0 | 3 | 0 | 64° – 73° |
| November | 74° | 46° | 0.8" | 0 | 4 | 0 | 52° – 65° |
| December | 66° | 41° | 2.0" | 0 | 6 | 0 | 49° – 60° |
| Year | 80° | 51° | 13.2" | 0.0" | 43 | 0 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in San Bernardino
San Bernardino gets 13 inches of rain and melted snow a year. February is the wettest month and June the driest. Rain or snow falls on about 43 days a year.
A year-round growing season
Heating and cooling a home in San Bernardino
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In San Bernardino, 48% of that work is heating and 52% is cooling.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
San Bernardino and its neighbors
San Bernardino borders 6 towns with climate data. January nights across them vary by 2.4°. Highland has both the coldest January nights (41°) and the hottest July afternoons (97°). San Bernardino’s January low is 42° and its July high 96°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How San Bernardino compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in San Bernardino averaged 2.1° warmer than the 1900s. The biggest change is in January (+2.9°). The shift is larger than in 96% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at San Bernardino’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 48° to 65°. August is the most reliable, staying within 7°.
Common questions about San Bernardino’s climate
What is the coldest month in San Bernardino?
December, with a typical high of 66° and a low of 41°.
What is the hottest month in San Bernardino?
August, with a typical high of 97° and a low of 64°. About 104 days a year reach 90°.
How much snow does San Bernardino get?
Almost none. A normal year brings 0.0 inches.
When is the first frost in San Bernardino?
Frost is uncommon. Only 88% of years see a night at 32° or below.
What is the rainiest month in San Bernardino?
February, with 3.5 inches of rain and melted snow. The year totals 13 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for San Bernardino itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Redlands, CA (9 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.