Climate averages 1991–2020
El Cajon weather
in January.
A mild, moderately wet month: the 10th warmest and the 11th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
January is a mild month in El Cajon: daytime highs average 17.9°C and nights cool to about 7.9°C. By daytime temperature it is the 10th warmest of the 12 months.
Expect about 57 mm of rain on roughly 6 days, which makes January a moderately wet month (the 11th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 10 h 15 min on an average January day.
The nearest other city in this atlas is Chula Vista (21 km away). In January its highs average 17.1°C, 0.9°C cooler than El Cajon, with 57 mm of rain.
Among the 498 cities listed in the United States, El Cajon ranks joint 73rd of 498 for the warmest January highs and joint 145th of 498 for the driest January (rainfall, lowest first). The mean January high of those 498 cities is 9.5°C; El Cajon is 8.5°C warmer than that mean.
From January to February, average highs fall by 0.2°C to 17.7°C, and monthly rainfall rises from 57 mm to 74 mm.
The annual picture
January 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, selected | 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 | 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
January in nearby cities
- Chula Vista in JanuaryUnited States · 21 kmHigh 17.1°C · Low 9.3°C · 57 mm rain
- San Diego in JanuaryUnited States · 21 kmHigh 17.4°C · Low 8.7°C · 50 mm rain
- Tijuana in JanuaryMexico · 33 kmHigh 16.9°C · Low 9.0°C · 63 mm rain
- Escondido in JanuaryUnited States · 38 kmHigh 17.7°C · Low 5.7°C · 75 mm rain
- San Marcos in JanuaryUnited States · 43 kmHigh 16.8°C · Low 6.1°C · 73 mm rain
- Rosarito in JanuaryMexico · 49 kmHigh 17.2°C · Low 9.9°C · 56 mm rain
- Vista in JanuaryUnited States · 52 kmHigh 17.8°C · Low 6.5°C · 73 mm rain
- Oceanside in JanuaryUnited States · 59 kmHigh 16.9°C · Low 8.3°C · 62 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.