San Diego climate: monthly averages: annual mean temperature 17.0 C; warmest month Aug (23.1 C); coldest month Dec (12.2 C).
Annual mean temperature: 17.0 C
Warmest month: Aug (23.1 C)
Coldest month: Dec (12.2 C)
Wettest month: Feb (1.96 mm/day)
All-time record high: 40.9 C
All-time record low: -0.3 C
A consolidated reference for San Diego climate: monthly averages, rebuilt from public data on a schedule. Expect 12.2 C at the coldest (Dec) and 23.1 C at the warmest (Aug) — a 10.9 C spread. Expect a wet season rather than rain year-round: Feb brings 1.96 mm/day against 0.13 mm/day in Jul. Taken together that is roughly 271 mm of rain a year for the grid cell. Values come from a public open API; a successful result is cached so a later outage never blanks the page. Scroll for the month-by-month figures, or jump to a neighbouring location from the links below.
Annual mean temperature 17.0 C
Warmest month Aug (23.1 C)
Coldest month Dec (12.2 C)
Wettest month Feb (1.96 mm/day)
All-time record high 40.9 C
All-time record low -0.3 C
Annual precipitation 266 mm / year
Coordinates 32.71571, -117.16472
Population 1,404,452
Average monthly temperature and rainfall in San Diego
Month
Mean temp (C)
Rain (mm/day)
Record high (C)
Record low (C)
Jan
12.4
1.32
27.6
-0.3
Feb
12.5
1.96
28.9
1.8
Mar
13.8
0.94
30.1
4.5
Apr
14.8
0.58
33.1
5.0
May
16.6
0.24
35.3
7.5
Jun
19.1
0.46
38.8
8.4
Jul
22.5
0.13
40.9
11.1
Aug
23.1
0.13
37.8
10.8
Sep
22.4
0.19
39.1
11.4
Oct
19.1
0.47
36.9
7.2
Nov
15.6
0.83
31.6
2.6
Dec
12.2
1.65
27.2
1.8
What the San Diego climate table shows
Values are multi-decadal climatological averages for the 32.71571, -117.16472 grid cell, not a single year. Rain is the daily mean, so a value of 2.00 mm/day is about 60 mm across a 30-day month. Averages smooth over extremes, so use them for planning rather than for what to pack for next Tuesday.
Frequently asked questions
Why do the numbers differ from a weather app?
An app shows one location on one day. These are long-run averages, so they smooth out single hot or cold spells.
How much rain is 1.96 mm/day in a month?
Rain is recorded as a daily mean, so 1.96 mm/day is roughly 60 mm across a 30-day month.