San Diego in Fall

In fall (September, October and November), San Diego sees average daytime highs around 29°C and overnight lows near 22°C, with 1334 mm of rain over about 86 wet days across the season. It is the coldest season of the year and the wettest season of the year.

Across fall, daytime highs hold fairly steady around 29°C. The sky is clear or mostly clear about 4% of the time across fall, and the air most often feels muggy.

Fall is San Diego's 3rd-best season to visit on our travel score. For the whole year in context, see San Diego's year-round climate.

Avg daytime high
29°C
coldest season of the year
Avg overnight low
22°C
Rainfall
1334 mm
86 wet days
Avg wind
4 km/h
Travel score
3.0
3rd-best season
Months
Sep · Oct · Nov

Temperature in San Diego in Fall

Average highAverage lowShaded bands: 10–90% of days

Across fall, daytime highs hold fairly steady around 29°C.

A typical fall day in San Diego reaches about 29°C and drops to 22°C overnight. The warmest of the three months is September, the coolest November.

15°20°25°30°35°SepOctNov

How fall really feels in San Diego

Once humidity and wind are folded in, fall brings about 0 days that feel above 32°C and 0 that feel at or below 0°C.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

fall sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

San Diego weather by month

How the three fall months (September, October and November) compare with the rest of the year — the season's months are highlighted.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan30° / 20°53711.55.8
Feb30° / 21°74811.75.5
Mar30° / 21°18914.511.94.7
Apr29° / 22°41024.212.23.4
May29° / 23°56930.612.52.7
Jun30° / 22°38528.212.62.8
Jul30° / 22°26027.312.52.7
Aug30° / 22°37928.812.32.6
Sep30° / 22°47129.412.12.6
Oct29° / 22°5083011.82.9
Nov28° / 21°35526.311.53.5
Dec29° / 21°1301611.44.8

Cloud cover in Fall

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 4% of the time across fall.

0%25%50%75%100%SepOctNov

Chance of precipitation in Fall

Any precipitation

San Diego gets around 1334 mm of rain over 86 wet days across fall. The line is the day-by-day chance of measurable precipitation.

0%20%40%60%80%100%SepOctNov

Humidity in Fall

DryComfortableHumidMuggyOppressiveMiserable

Most of fall feels muggy — the stacked bands show each day's mix of comfort levels, read off the dew point.

0%25%50%75%100%SepOctNov

Wind in Fall

Winds average 4 km/h across fall.

0246810SepOctNov

Sunrise & sunset in Fall

DaylightNight

Daylight runs from about 12 h 12 min in early September to 11 h 24 min by late November. The lit band spans sunrise to sunset each day.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMSepOctNov

Solar energy in Fall

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day across fall, about 4.5 kWh/m².

024SepOctNov
Planning a trip in fall

Is fall a good time to visit San Diego?

Our two travel scores rate fall for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.

3.0
Sightseeing
3rd-best month of the year
3.8
Beach & pool
3rd-best month of the year

fall is a weaker month for outdoor sightseeing in San Diego.

What to pack for San Diego in Fall

From fall's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In fall, San Diego sees daytime highs around 29°C and nights near 22°C. Pack light clothes and rain gear. Worth having: sun protection. About 86 days see rain.

light clothesrain gearsun protection

UV index in San Diego in Fall

LowModerateHighVery highExtreme

Clear-sky midday UV across fall averages around 12 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in San Diego peaks around April 12 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 12 at about 10 (very high).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highApr 12UV 14Dec 12UV 10
UV index (midday)Level
Jan11Extreme
Feb13Extreme
Mar13Extreme
Apr14Extreme
May12Extreme
Jun13Extreme
Jul12Extreme
Aug13Extreme
Sep13Extreme
Oct12Extreme
Nov10Extreme
Dec10Very high

Air quality in San Diego in Fall

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where fall falls, not just the annual average.

Air quality in San Diego is worst in March — around 34 µg/m³ PM2.5 (moderate), about 3.6× the cleanest month (December, 9 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

010203040JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodMar 1832 µg/m³Dec 119 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb19Moderate
Mar34Moderate
Apr23Moderate
May20Moderate
Jun21Moderate
Jul21Moderate
Aug17Moderate
Sep13Moderate
Oct12Good
Nov10Good
Dec9Good
Location & terrain

Where is San Diego?

San Diego sits at 10.3°N, 73.2°W, 180 m above sea level, in Colombia. The nearest listed city is Valledupar, 17 km away.

Topography around San Diego

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of San Diego.

Within 3 km, the terrain around San Diego has only modest variations in elevation — a maximum elevation change of 215 m around an average of 170 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,747 m; within 80 km, extreme variations in elevation — a maximum elevation change of 5,632 m.

The land around San Diego is covered by grassland (49%) and trees (40%) within 3 km, trees (55%) and grassland (38%) within 16 km, and trees (64%) and grassland (31%) within 80 km.

3 km
215 m
16 km
1,747 m
80 km
5,632 m
treesshrubsgrasslandcroplandartificial surfacesbare terrain
Fall weather nearby: Valledupar 17 km · Agustín Codazzi 34 km · Villanueva 38 km · San Juan del Cesar 52 km · Becerril 71 km · Fonseca 71 km · Machiques 75 km · Barrancas 81 km

Colombia travel facts

Travel advisory
Level 3
Reconsider Travel
Power plugs
Type A / B
120 / 240 V · 60 Hz
Prices
≈ 38% of US
price level, 2025
GDP per capita
$8,562
2025
Happiness
6.0 / 10
World Happiness, 2025
Safe drinking water
74%
of population, 2024
Homicide rate
24.9
per 100k, 2023
Road deaths
15.4
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Low
EF EPI 480
Religion
Roman Catholic 64%Protestant 17%none 14%atheist 1%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for San Diego (10.3338°, -73.1805°, elevation 180 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.