El Cajon climate
El Cajon (California, United States) has a hot semi-arid climate (Köppen BSh). The average temperature over the year is 20 °C68 °F, and about 320 mm13 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
El Cajon climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin |
|---|---|---|---|---|
| Jan | 1967 | 947 | 1457 | 542.1 |
| Feb | 2067 | 948 | 1458 | 702.7 |
| Mar | 2272 | 1050 | 1661 | 351.4 |
| Apr | 2475 | 1152 | 1763 | 220.9 |
| May | 2781 | 1356 | 2068 | 90.4 |
| Jun | 3188 | 1660 | 2474 | 20.1 |
| Jul | 3595 | 2068 | 2781 | 60.2 |
| Aug | 3596 | 2068 | 2882 | 60.2 |
| Sep | 3492 | 1966 | 2679 | 70.3 |
| Oct | 2883 | 1560 | 2272 | 180.7 |
| Nov | 2374 | 1253 | 1864 | 301.2 |
| Dec | 1966 | 847 | 1456 | 612.4 |
| Year | 3596 | 847 | 2068 | 32013 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 61% | 38% | 3.5 | 10:13 |
| Feb | 64% | 43% | 4.3 | 10:58 |
| Mar | 65% | 39% | 5.7 | 11:53 |
| Apr | 64% | 35% | 7.0 | 12:57 |
| May | 62% | 31% | 7.7 | 13:50 |
| Jun | 54% | 21% | 8.3 | 14:18 |
| Jul | 48% | 25% | 7.7 | 14:07 |
| Aug | 46% | 20% | 7.3 | 13:21 |
| Sep | 48% | 20% | 6.3 | 12:19 |
| Oct | 53% | 26% | 5.0 | 11:18 |
| Nov | 55% | 32% | 3.8 | 10:25 |
| Dec | 62% | 40% | 3.1 | 9:00 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of El Cajon is like
The warmest month is August, with an average high of 35 °C96 °F and a low of 20 °C68 °F. The coldest is December, when highs average 19 °C66 °F and lows 8 °C47 °F. There is a clear seasonal cycle, with 14.2 °C25.6 °F between the average temperature of the warmest and the coolest month.
It is dry, with about 320 mm13 in of precipitation per year. The wettest three-month stretch is December–February, which brings 58% of the annual total. Months with less than 20 mm0.8 in on average: May–October. The wettest month is February (70 mm2.7 in), the driest is June (2 mm0.1 in).
Relative humidity ranges from 46% in August to 65% in March. The clearest skies (lowest average cloud amount, 20%) are typical of September. Average wind speed near the ground ranges from 7 km/h (4 mph) in September to 10 km/h (6 mph) in April. Daylight lasts from about 10.0 hours in December to 14.3 hours in June.
Best time to visit El Cajon
Based on these averages, the most comfortable months for sightseeing and outdoor activities are October–May: average highs of 19 °C66 °F to 28 °C83 °F with 9 mm0.4 in to 70 mm2.7 in of precipitation per month.
The most challenging month is August, which is hot, with average highs of 35 °C96 °F.
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
What to pack for El Cajon
- Winter (December–February) — highs 1966 to 20 °C67 °F, lows 847 to 9 °C48 °F, about 62 mm2.4 in of precipitation a month. Pack light layers — T-shirts plus a light sweater or jacket and an extra layer for the cooler mornings and evenings.
- Spring (March–May) — highs 2272 to 27 °C81 °F, lows 1050 to 13 °C56 °F, about 22 mm0.9 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses and an extra layer for the cooler mornings and evenings.
- Summer (June–August) — highs 3188 to 35 °C96 °F, lows 1660 to 20 °C68 °F, about 4 mm0.2 in of precipitation a month. Pack very light, breathable clothing, a sun hat and plenty of water.
- Autumn (September–November) — highs 2374 to 34 °C92 °F, lows 1253 to 19 °C66 °F, about 18 mm0.7 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses and an extra layer for the cooler mornings and evenings.
How El Cajon compares
Compared with San Diego, about 21 km to the southwest, El Cajon is on average 0.5 °C1 °F warmer and receives 19% more precipitation (320 mm13 in vs 269 mm11 in). The difference is largest in July (2.5 °C4.5 °F warmer).
Of the 222 places in the United States covered by World Climates, El Cajon is the 33rd warmest by annual mean temperature and the 201st wettest by annual precipitation. See all of them on the United States climate page.
Places in other countries with the most similar temperature and rainfall pattern: Irákleion (Greece, Csa), Haifa (Israel, Csa) and Guelmim (Morocco, BWh).
Nearby places
- San Diego 21 km · 19 °C67 °F · 269 mm11 in
- Tijuana 33 km · 19 °C66 °F · 269 mm11 in
- Escondido 38 km · 20 °C67 °F · 320 mm13 in
- Oceanside 59 km · 18 °C64 °F · 314 mm12 in
- Temecula 80 km · 20 °C68 °F · 299 mm12 in
- Murrieta 88 km · 17 °C63 °F · 298 mm12 in
- Ensenada 108 km · 19 °C66 °F · 255 mm10 in
- Riverside 135 km · 20 °C68 °F · 289 mm11 in
Frequently asked questions
What is the warmest month in El Cajon?
August is the warmest month in El Cajon, with an average high of 35 °C (96 °F) and an average low of 20 °C (68 °F).
What is the coldest month in El Cajon?
December is the coldest month, with an average high of 19 °C (66 °F) and an average low of 8 °C (47 °F).
When does it rain the most in El Cajon?
February is the wettest month with about 70 mm (2.7 in) of precipitation; June is the driest with about 2 mm (0.1 in).
What is the best time to visit El Cajon?
Judging by long-term averages, the most comfortable months are October–May.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.
The grid cell’s average elevation is 584 m, while El Cajon lies at about 133 m. Temperatures on this page were therefore adjusted by +2.9 °C5.3 °F using the standard lapse rate of 6.5 °C per 1,000 m.