San Jose, CA climate
San Jose has mild winters and warm summers, with very little rain. A typical July afternoon reaches 86°, a January night drops to 39°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in San Jose feels like
Winter
Spring
Summer
Fall
San Jose 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 | 60° | 39° | 2.9" | 0 | 10 | 0 | 46° – 54° |
| February | 63° | 42° | 3.0" | 0 | 9 | 0 | 46° – 58° |
| March | 68° | 44° | 2.4" | 0 | 9 | 0 | 50° – 62° |
| April | 71° | 45° | 1.1" | 0 | 6 | 0 | 54° – 62° |
| May | 76° | 49° | 0.5" | 0 | 2 | 0 | 57° – 69° |
| June | 83° | 53° | 0.1" | 0 | 1 | 0 | 64° – 71° |
| July | 86° | 56° | 0.0" | 0 | 0 | 0 | 68° – 75° |
| August | 86° | 56° | 0.0" | 0 | 0 | 0 | 68° – 74° |
| September | 84° | 54° | 0.1" | 0 | 0 | 0 | 65° – 73° |
| October | 78° | 49° | 0.7" | 0 | 3 | 0 | 60° – 70° |
| November | 67° | 43° | 1.4" | 0 | 6 | 0 | 48° – 59° |
| December | 59° | 39° | 2.6" | 0 | 10 | 0 | 45° – 52° |
| Year | 73° | 47° | 14.7" | 0.0" | 56 | 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 Jose
San Jose gets 15 inches of rain and melted snow a year. February is the wettest month and July the driest. Rain or snow falls on about 56 days a year.
About 310 frost-free days a year
In half of years the last 32° night comes by February 2 and the first one by December 6. That leaves about 310 frost-free days for gardens, longer than 95% of U.S. towns.
Heating and cooling a home in San Jose
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In San Jose, 80% of that work is heating and 20% is cooling, so the furnace matters far more than the air conditioner.
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 Jose and its neighbors
San Jose borders 11 towns with climate data. January nights across them vary by 2.6°. Morgan Hill has the coldest January nights (38°) and Alum Rock the hottest July afternoons (86°). San Jose’s January low is 39° and its July high 86°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How San Jose 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 Jose averaged 1.9° warmer than the 1900s. The biggest change is in August (+2.4°). The shift is larger than in 91% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at San Jose’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 46° to 58°. August is the most reliable, staying within 6°.
Common questions about San Jose’s climate
What is the coldest month in San Jose?
December, with a typical high of 59° and a low of 39°.
What is the hottest month in San Jose?
July, with a typical high of 86° and a low of 56°. About 27 days a year reach 90°.
How much snow does San Jose get?
Almost none. A normal year brings 0.0 inches.
When is the first frost in San Jose?
In half of years the first 32° night comes by December 6, and the last spring frost by February 2.
What is the rainiest month in San Jose?
February, with 3.0 inches of rain and melted snow. The year totals 15 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for San Jose itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Los Gatos, CA (9 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.