San Diego, CA Climate: Temperature & Rain by Month
Annual temperature and rainfall from NOAA NCEI's 1991–2020 normals →; comfort score computed by PlainClimate
- Warmer national band · Avg annual temp
- 65°FAnnual mean temperature: 64.7°F. National station-mapped location corpus median: 52.2°F across 6,861 measured records.
- Drier national band · Annual precip
- 9.8"Annual precipitation: 9.8 inches. National station-mapped location corpus median: 36.2 inches across 6,352 measured records.
30-year climate normals (1991-2020) from San Diego's primary NOAA station, SAN DIEGO LINDBERGH FLD.
The climate verdict for San Diego
Dryness leads the climate profile for San Diego, California, with 9.8 inches of precipitation a year. NOAA records an annual average of 65°F. August is the warmest month at 72°F and December the coldest at 58°F.
- 65°F
- average temperature, NOAA 1991-2020 normal
- 9.8"
- annual precipitation
Based on NOAA U.S. Climate Normals (1991–2020) - 30-year averages describing the typical year, not a forecast.
Avg Temperature
65°F (18°C)Annual mean temperature: 64.7°F. National station-mapped location corpus median: 52.2°F across 6,861 measured records.
Warmer national band
Avg High
71°FAnnual average daily high: 70.9°F. National station-mapped location corpus median: 63.8°F across 6,861 measured records.
Warmer than median
Avg Low
59°FAnnual average daily low: 58.5°F. National station-mapped location corpus median: 41.1°F across 6,861 measured records.
Warmer national band
Annual Precip
9.8"Annual precipitation: 9.8 inches. National station-mapped location corpus median: 36.2 inches across 6,352 measured records.
Drier national band
Climate Living Index · model supports three NOAA data products
San Diego's broader climate profile: 72/100
A percentile-benchmarked model across annual, daily, and hourly climate normals. This record uses 3 measured NOAA products; every input remains inspectable.
PlainClimate-derived, not an official NOAA rating. This separate index does not replace the established Comfort Score used in rankings, and it is not a verdict on safety, health, housing, culture, or overall quality of life.
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Annual temperature balance
64.7°F · 2.8° from 67.5°F
91/100 A · weight 25%Distance from a 67.5°F annual mean; smaller is better.
NOAA annual/seasonal normals ·
ANN-TAVG-NORMAL -
Precipitation balance
9.8 in · 25.2 from 35 in
12/100 F · weight 15%Distance from 35 annual inches; smaller is better.
NOAA annual/seasonal normals ·
ANN-PRCP-NORMAL -
Snowfall burden
Not measured
N/A N/A · weight 10%Not scored; its 10% weight redistributes across measured dimensions.
Annual snowfall; lower is better in this formula.
NOAA annual/seasonal normals ·
ANN-SNOW-NORMAL -
Frost-free season
Not measured
N/A N/A · weight 10%Not scored; its 10% weight redistributes across measured dimensions.
Days between NOAA 50% spring and fall freeze dates; longer is better.
NOAA annual/seasonal normals ·
ANN-TMIN-PRBLST-T32FP50 + ANN-TMIN-PRBFST-T32FP50 -
Normal heat + freeze calendar
0 calendar days
100/100 A · weight 25%Normal high ≥90°F days plus normal low ≤32°F days; lower is better.
NOAA daily multivariate normals ·
DLY-TMAX-NORMAL + DLY-TMIN-NORMAL (derived counts) -
Summer moisture balance
61.4°F mean dew point
53/100 D · weight 15%June–August mean dew point distance from 52.5°F; smaller is better.
NOAA hourly normals ·
HLY-DEWP-NORMAL
Live national benchmark table and calculation
Each raw metric is linearly interpolated across its live p10, p25, p50, p75, and p90 breakpoints. Equal-valued breakpoints collapse to their mean percentile; values outside p10-p90 extrapolate toward 0 or 100 using the nearest non-flat segment, then clamp to that range. Scores favor the direction shown, then combine by the listed weights. Missing dimensions are removed from both the weighted sum and available weight before normalization.
| Dimension | Weight | Better | p10 | p25 | p50 | p75 | p90 | n |
|---|---|---|---|---|---|---|---|---|
| Annual temperature balance | 25% | Lower | 3.4 | 7.9 | 15.3 | 21 | 25.2 | 6,861 |
| Precipitation balance | 15% | Lower | 2.7 | 7.1 | 14.2 | 20.9 | 25.7 | 6,352 |
| Snowfall burden | 10% | Lower | 0 | 2.1 | 18.9 | 42.7 | 69.8 | 4,098 |
| Frost-free season | 10% | Higher | 127 | 150 | 180 | 215 | 253 | 6,446 |
| Normal heat + freeze calendar | 25% | Lower | 56 | 102 | 145 | 180 | 207 | 6,859 |
| Summer moisture balance | 15% | Lower | 2.7 | 6.1 | 9.3 | 14.8 | 18.4 | 417 |
Grades: A 85–100 · B 70–84 · C 55–69 · D 40–54 · F below 40.
Source: NOAA NCEI U.S. Climate Normals v1.0.1 (1991–2020). This record uses NOAA annual/seasonal normals and NOAA daily multivariate normals and NOAA hourly normals; the model also supports hourly normals where published · data updated 2026-08-04. Full methodology and limits.
How San Diego compares with its closest stations
Against the 6 closest stations in the record, San Diego averages 65°F a year, warmer than North Island, CA (64°F) and San Diego Seaworld, CA (62°F).
Corpus-relative placement
Where San Diego sits across the climate record
These comparisons place this primary-station normal among station-mapped locations with the same NOAA 1991–2020 fields.
- Annual temperature
- Warmer than 87%
- of 6,861 measured location normals.
- Annual precipitation
- Wetter than 6%
- of 6,352 measured location normals.
- Seasonal temperature swing
- Larger than 2%
- of 6,861 complete location-year normals.
San Diego's measured station temperature trend
MethodologyAcross 146 complete annual observations from 1865 to 2025, SAN DIEGO LINDBERGH FLD warmed at a fitted rate of 0.17°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- San Diego primary station fitted change +0.17 °C/decade
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|
| January | 66°F (19°C) | 50°F (10°C) | 58°F (15°C) | 2.0" | 0.0 | 0.0 |
| February | 66°F (19°C) | 52°F (11°C) | 59°F (15°C) | 2.2" | 0.0 | 0.0 |
| March | 67°F (19°C) | 55°F (13°C) | 61°F (16°C) | 1.5" | 0.0 | 0.1 |
| April | 69°F (20°C) | 57°F (14°C) | 63°F (17°C) | 0.7" | 0.0 | 0.2 |
| May | 70°F (21°C) | 60°F (16°C) | 65°F (18°C) | 0.3" | 0.0 | 0.3 |
| June | 72°F (22°C) | 63°F (17°C) | 67°F (20°C) | 0.1" | 0.0 | 0.1 |
| July | 75°F (24°C) | 66°F (19°C) | 71°F (22°C) | 0.1" | 0.0 | 0.1 |
| August | 77°F (25°C) | 68°F (20°C) | 72°F (22°C) | 0.0" | 0.0 | 0.3 |
| September | 77°F (25°C) | 66°F (19°C) | 72°F (22°C) | 0.1" | 0.0 | 0.9 |
| October | 75°F (24°C) | 62°F (16°C) | 68°F (20°C) | 0.5" | 0.0 | 0.8 |
| November | 71°F (22°C) | 55°F (13°C) | 63°F (17°C) | 0.8" | 0.0 | 0.3 |
| December | 66°F (19°C) | 50°F (10°C) | 58°F (14°C) | 1.7" | 0.0 | 0.0 |
The year, day by day
The calendar barely moves in San Diego: no date carries a normal high of 90°F or a normal low at freezing. The year runs between 49°F near December 19 and 78°F near August 31.
No freezing date
Not one calendar date in the 1991–2020 record carries a normal low at or below 32°F. The coldest normal low of the year is 49°F around December 19.
Where the wet dates fall
The likeliest wet date is February 20, when 25% of years recorded at least a hundredth of an inch. The driest is August 9 at 1%. Summed across the calendar, that is about 40 wet dates a year.
The widest day
January 6 carries the biggest normal gap between afternoon and dawn, 16°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for San Diego.
Where San Diego Stands Nationally
Aridity defines the water calendar: about 10 inches in a normal year lands this among the driest tenth of ranked stations.
Among the steadiest day-night climates ranked: even the widest normal daily swing holds to roughly 16°F.
Standing computed against the distribution of 6,860 NOAA 1991–2020 normals stations in the PlainClimate database; only nationally notable standings are shown.
Monthly Precipitation
Average monthly rainfall
6.5 days with precipitation
7.1 days with precipitation
6.2 days with precipitation
3.8 days with precipitation
2.2 days with precipitation
0.7 days with precipitation
0.7 days with precipitation
0.3 days with precipitation
0.9 days with precipitation
2.4 days with precipitation
3.7 days with precipitation
5.8 days with precipitation
San Diego's wet season runs through the cold months
December, January and February carry 60% of the year's precipitation here, while June through August contribute 1%. That is the cool-season-dominant pattern of the West Coast and the higher inland West, where storm tracks swing south in winter and summer turns dry; the thermometer meanwhile shows an unusually narrow 14.5°F seasonal spread.
- Wettest month
- February, 2.2"
- Driest month
- August, 0.0"
- Wettest three months
- February, January, December (60% of the year)
Shares are computed from this station's own 1991-2020 monthly precipitation normals. A cool-season label means the December-February share reaches 35%. Where snow falls, the monthly figures above report liquid-equivalent precipitation, so a wet winter month is not necessarily a rainy one.
How San Diego's precipitation splits across the calendar
About 40 days a year record measurable precipitation here, carrying 9.8" between them, or roughly 0.24 inches on a typical wet day. That sits in the middle band: neither the many-light-days pattern of the Pacific Northwest and the Great Lakes, nor the few-heavy-events pattern of the Gulf and the desert Southwest.
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year and say nothing about the heaviest single storm on record.
Frost Dates & Growing Season
First Fall Freeze
N/A
50% probability date
Last Spring Freeze
N/A
50% probability date
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
990
Higher = more heating needed
Cooling Degree Days
893
Higher = more cooling needed
Warmest Month
August
Coldest Month
December
Humidity & Wind
Monthly averages from hourly observations
| Month | Humidity | Wind (mph) | Clear Sky % | Overcast % |
|---|---|---|---|---|
| January | 62% | 5.1 | 26% | 19% |
| February | 64% | 6.2 | 17% | 23% |
| March | 65% | 6.8 | 18% | 26% |
| April | 67% | 7.1 | 19% | 28% |
| May | 72% | 7.1 | 13% | 30% |
| June | 74% | 6.8 | 13% | 22% |
| July | 76% | 6.7 | 10% | 19% |
| August | 74% | 6.5 | 18% | 17% |
| September | 70% | 5.8 | 24% | 25% |
| October | 63% | 4.9 | 30% | 16% |
| November | 60% | 4.6 | 32% | 15% |
| December | 60% | 4.6 | 26% | 19% |
Places with a similar climate profile
NOAA 1991–2020 annual normals connect this location to non-geographic peers. Temperature peers use annual mean temperature; energy peers use both heating and cooling degree days.
Closest annual-temperature peers
What San Diego's climate means for you
San Diego runs 65°F a year - peaking in August, coldest in December.
- Both loads matter across the year, 990 heating and 893 cooling degree days, so shoulder-season efficiency pays here.
- See how San Diego lines up against the rest of California and the national rankings. See rankings
Climate Guides
Data-derived climate profile
How San Diego's climate pattern fits together
mixed demand · dry · low swing
Local precipitation is sparse in this otherwise mixed profile. The station reports 9.8 inches annually, within PlainClimate's dry band. Snowfall is not added to the interpretation because its annual value is missing. The monthly distribution matters because the total alone does not reveal the timing.
The calendar stays thermally compact and dry. August and December mark the typical warm and cold ends of the calendar, only 14.5°F apart, while the annual precipitation total remains below PlainClimate's dry threshold. The annual average is 65°F. The monthly rows show whether that limited precipitation is spread through the year or concentrated in a shorter interval.
San Diego combines a compact 14.5°F annual temperature range with meaningful demand on both sides of the thermostat: 990 heating and 893 cooling degree days. The balance matters more here than either annual total in isolation.
A frost-free growing-season length is not available for San Diego. That missing field is kept separate from the observed temperature and precipitation record rather than filled from a regional estimate.
These labels group NOAA 1991-2020 normals from San Diego's primary station, where heating and cooling demand are close enough that neither season sets the character on its own. They are descriptive ranges, not an official NOAA classification or a forecast for any specific year.
The year in four calendar signals
- Warmest normal
- August
- The month averages 72°F (22°C), a middling summer peak by national standards rather than an extreme one.
- Coldest normal
- December
- The coldest month still averages 58°F (14°C), above freezing, so this calendar has no hard winter.
- Rainfall rhythm
- February to August
- February is typically wettest; August is driest.
- Mild-temperature window
- January through December
- Monthly means sit between 55°F and 75°F in this window.
Frequently Asked Questions
What is the average temperature in San Diego, CA? ▼
How dry is San Diego? ▼
How much energy does heating and cooling require in San Diego? ▼
Where does this San Diego climate data come from? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from San Diego's primary station: SAN DIEGO LINDBERGH FLD (USW00023188). For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The 2024 Census Gazetteer identifies the exact name-and-state match as an incorporated place (GEOID 0666000). The reproducible method is an exact normalized name-and-state match; unresolved is an upper bound on facilities because spelling variants can be missed.
Related
Every figure on PlainClimate is rendered directly from NOAA 1991-2020 U.S. Climate Normals data, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.