Climate averages 1991–2020
El Cajon weather
in August.
A hot, very dry month: the warmest and one of the driest of the year. Meets the pleasant-weather rule
Long-term climate patterns, not a forecast for a particular trip.
August is a hot month in El Cajon: daytime highs average 28.3°C and nights cool to about 18.7°C. By daytime temperature it is the warmest month of the year.
Expect about 1.8 mm of rain on fewer than one day, which makes August a very dry month (one of the driest months of the year). Daylight, from sunrise to sunset, lasts about 13 h 22 min on an average August day.
The nearest other city in this atlas is Chula Vista (21 km away). In August its highs average 24.5°C, 3.8°C cooler than El Cajon, with 1.8 mm of rain.
Among the 498 cities listed in the United States, El Cajon ranks joint 310th of 498 for the warmest August highs and joint 83rd of 498 for the driest August (rainfall, lowest first). The mean August high of those 498 cities is 29.9°C; El Cajon is 1.6°C cooler than that mean.
From August to September, average highs fall by 0.7°C to 27.6°C, and monthly rainfall rises from 1.8 mm to 4.4 mm.
The annual picture
August in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
El Cajon climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 17.9°C7.9°C | 7.9°C | 57 | 5.6 | 10.310 h |
| February | 17.7°C8.3°C | 8.3°C | 74 | 6.9 | 11.011 h |
| March | 18.6°C9.4°C | 9.4°C | 48 | 5.8 | 12.012 h |
| April | 20.2°C10.9°C | 10.9°C | 23 | 3.9 | 13.013 h |
| May | 21.7°C13.0°C | 13.0°C | 10 | 2.0 | 13.814 h |
| June | 24.5°C15.1°C | 15.1°C | 1.8 | 0.6 | 14.314 h |
| July | 27.2°C17.7°C | 17.7°C | 2.6 | 0.7 | 14.114 h |
| August, selected | 28.3°C18.7°C | 18.7°C | 1.8 | 0.5 | 13.413 h |
| September | 27.6°C17.8°C | 17.8°C | 4.4 | 0.9 | 12.412 h |
| October | 24.6°C14.6°C | 14.6°C | 15 | 2.5 | 11.411 h |
| November | 21.2°C11.0°C | 11.0°C | 24 | 3.3 | 10.511 h |
| December | 17.7°C7.9°C | 7.9°C | 47 | 5.3 | 10.010 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
August in nearby cities
- Chula Vista in AugustUnited States · 21 kmHigh 24.5°C · Low 18.1°C · 1.8 mm rain
- San Diego in AugustUnited States · 21 kmHigh 25.4°C · Low 18.0°C · 0.4 mm rain
- Tijuana in AugustMexico · 33 kmHigh 24.8°C · Low 18.6°C · 1.2 mm rain
- Escondido in AugustUnited States · 38 kmHigh 29.1°C · Low 18.8°C · 2.6 mm rain
- San Marcos in AugustUnited States · 43 kmHigh 26.9°C · Low 18.2°C · 1.0 mm rain
- Rosarito in AugustMexico · 49 kmHigh 24.9°C · Low 19.3°C · 0.4 mm rain
- Vista in AugustUnited States · 52 kmHigh 28.9°C · Low 19.4°C · 1.0 mm rain
- Oceanside in AugustUnited States · 59 kmHigh 25.8°C · Low 19.1°C · 0.6 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for El Cajon) is explained once on the El Cajon year overview and on the Sources, method and limits page.
Chula Vista lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.