Climate averages 1991–2020
Pasadena (California), United States weather
in August.
A hot, very dry month: the warmest and the driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
August is a hot month in Pasadena (California), United States: daytime highs average 31.7°C and nights cool to about 17.9°C. By daytime temperature it is the warmest month of the year.
Rain is very rare: less than 1 mm falls in a typical August (the driest month of the year). Daylight, from sunrise to sunset, lasts about 13 h 26 min on an average August day.
The nearest other city in this atlas is Glendale (California), United States (10 km away). In August its highs average 31.7°C, about as warm as Pasadena (California), United States, with almost no rain (under 1 mm).
Among the 498 cities listed in the United States, Pasadena (California), United States ranks joint 142nd of 498 for the warmest August highs and joint 39th of 498 for the driest August (rainfall, lowest first). The mean August high of those 498 cities is 29.9°C; Pasadena (California), United States is 1.8°C warmer than that mean.
From August to September, average highs fall by 1.5°C to 30.2°C, and monthly rainfall rises from under 1 mm to 3.9 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
Pasadena (California), United States climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 17.8°C6.1°C | 6.1°C | 86 | 5.8 | 10.210 h |
| February | 18.0°C6.4°C | 6.4°C | 95 | 6.7 | 10.911 h |
| March | 19.7°C7.7°C | 7.7°C | 64 | 6.1 | 12.012 h |
| April | 22.1°C9.1°C | 9.1°C | 24 | 3.6 | 13.013 h |
| May | 24.1°C11.6°C | 11.6°C | 12 | 2.3 | 13.914 h |
| June | 27.2°C14.3°C | 14.3°C | 2.3 | 0.5 | 14.414 h |
| July | 30.5°C17.2°C | 17.2°C | 3.1 | 0.6 | 14.214 h |
| August, selected | 31.7°C17.9°C | 17.9°C | 0.9 | 0.2 | 13.413 h |
| September | 30.2°C16.5°C | 16.5°C | 3.9 | 0.9 | 12.412 h |
| October | 26.2°C12.9°C | 12.9°C | 18 | 2.3 | 11.411 h |
| November | 21.8°C9.1°C | 9.1°C | 22 | 3.0 | 10.410 h |
| December | 17.6°C5.8°C | 5.8°C | 58 | 5.2 | 9.910 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
- Glendale (California), United States in AugustUnited States · 10 kmHigh 31.7°C · Low 18.2°C · 0.9 mm rain
- El Monte in AugustUnited States · 14 kmHigh 32.9°C · Low 19.2°C · 0.5 mm rain
- East Los Angeles in AugustUnited States · 14 kmHigh 30.6°C · Low 18.4°C · 0.3 mm rain
- Los Angeles in AugustUnited States · 14 kmHigh 32.4°C · Low 18.7°C · 0.3 mm rain
- Burbank in AugustUnited States · 16 kmHigh 33.3°C · Low 19.6°C · 0.9 mm rain
- West Covina in AugustUnited States · 21 kmHigh 32.7°C · Low 19.1°C · 0.5 mm rain
- Whittier in AugustUnited States · 21 kmHigh 31.6°C · Low 18.7°C · 0.5 mm rain
- Downey in AugustUnited States · 23 kmHigh 30.4°C · Low 18.0°C · 0.3 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 Pasadena) is explained once on the Pasadena (California), United States year overview and on the Sources, method and limits page.
Glendale (California), United States and Burbank lie in the same rainfall cell, so their rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.