San Diego, CA climate
San Diego has warm winters and pleasant summers, with very little rain. A typical July afternoon reaches 80°, a January night drops to 45°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in San Diego feels like
Winter
Spring
Summer
Fall
San Diego 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 | 68° | 45° | 2.1" | 0 | 5 | 0 | 53° – 62° |
| February | 68° | 46° | 2.5" | 0 | 7 | 0 | 53° – 63° |
| March | 69° | 49° | 1.7" | 0 | 5 | 0 | 54° – 65° |
| April | 71° | 51° | 0.8" | 0 | 3 | 0 | 57° – 66° |
| May | 72° | 56° | 0.3" | 0 | 1 | 0 | 60° – 69° |
| June | 76° | 59° | 0.1" | 0 | 0 | 0 | 63° – 72° |
| July | 80° | 63° | 0.0" | 0 | 0 | 0 | 68° – 77° |
| August | 83° | 64° | 0.0" | 0 | 0 | 0 | 70° – 77° |
| September | 82° | 62° | 0.1" | 0 | 1 | 0 | 68° – 76° |
| October | 78° | 56° | 0.5" | 0 | 1 | 0 | 63° – 72° |
| November | 73° | 49° | 0.9" | 0 | 3 | 0 | 55° – 65° |
| December | 67° | 44° | 1.7" | 0 | 5 | 0 | 53° – 59° |
| Year | 74° | 54° | 10.7" | 0.0" | 33 | 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 Diego
San Diego gets 11 inches of rain and melted snow a year. February is the wettest month and August the driest. Rain or snow falls on about 33 days a year.
A year-round growing season
Heating and cooling a home in San Diego
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In San Diego, 56% of that work is heating and 44% 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 Diego and its neighbors
San Diego borders 12 towns with climate data. January nights across them vary by 6.2°. Escondido has both the coldest January nights (42°) and the hottest July afternoons (87°). San Diego’s January low is 45° and its July high 80°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How San Diego 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 Diego averaged 2.2° warmer than the 1900s. The biggest change is in January (+3.1°). The shift is larger than in 98% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at San Diego’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. March swings the most: between 1991 and 2020 its average temperature ranged from 54° to 65°. December is the most reliable, staying within 6°.
Common questions about San Diego’s climate
What is the coldest month in San Diego?
December, with a typical high of 67° and a low of 44°.
What is the hottest month in San Diego?
August, with a typical high of 83° and a low of 64°. About 16 days a year reach 90°.
How much snow does San Diego get?
Almost none. A normal year brings 0.0 inches.
When is the first frost in San Diego?
Frost is uncommon. Only 6% of years see a night at 32° or below.
What is the rainiest month in San Diego?
February, with 2.5 inches of rain and melted snow. The year totals 11 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for San Diego itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Chula Vista, CA (13 mi, snow) and San Diego Montgomery Fld, CA (1 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.