Climate averages 1991–2020
San Tan Valley weather
in August.
A very hot, fairly dry month: the 3rd warmest and the joint 8th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
August is a very hot month in San Tan Valley: daytime highs average 38.4°C and nights cool to about 26.2°C. By daytime temperature it is the 3rd warmest of the 12 months.
Expect about 27 mm of rain on roughly 5 days, which makes August a fairly dry month (the joint 8th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 13 h 23 min on an average August day.
The nearest other city in this atlas is Chandler (32 km away). In August its highs average 39.7°C, 1.3°C warmer than San Tan Valley, with 26 mm of rain.
Among the 498 cities listed in the United States, San Tan Valley ranks 13th of 498 for the warmest August highs and joint 145th of 498 for the driest August (rainfall, lowest first). The mean August high of those 498 cities is 29.9°C; San Tan Valley is 8.5°C warmer than that mean.
From August to September, average highs fall by 2.6°C to 35.9°C, and monthly rainfall falls from 27 mm to 26 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
San Tan Valley climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 18.2°C4.9°C | 4.9°C | 38 | 4.2 | 10.210 h |
| February | 19.8°C6.3°C | 6.3°C | 41 | 4.4 | 11.011 h |
| March | 23.8°C8.9°C | 8.9°C | 27 | 3.0 | 12.012 h |
| April | 28.2°C12.5°C | 12.5°C | 8.4 | 1.4 | 13.013 h |
| May | 33.2°C17.4°C | 17.4°C | 4.1 | 0.7 | 13.914 h |
| June | 38.7°C22.6°C | 22.6°C | 2.0 | 0.6 | 14.314 h |
| July | 39.3°C26.5°C | 26.5°C | 21 | 3.7 | 14.114 h |
| August, selected | 38.4°C26.2°C | 26.2°C | 27 | 4.9 | 13.413 h |
| September | 35.9°C22.7°C | 22.7°C | 26 | 3.2 | 12.412 h |
| October | 30.0°C15.9°C | 15.9°C | 18 | 2.4 | 11.411 h |
| November | 23.3°C9.6°C | 9.6°C | 19 | 2.4 | 10.510 h |
| December | 17.6°C4.8°C | 4.8°C | 34 | 4.3 | 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
- Chandler in AugustUnited States · 32 kmHigh 39.7°C · Low 26.8°C · 26 mm rain
- Mesa in AugustUnited States · 38 kmHigh 39.3°C · Low 26.9°C · 25 mm rain
- Tempe in AugustUnited States · 43 kmHigh 39.5°C · Low 27.3°C · 29 mm rain
- Scottsdale in AugustUnited States · 49 kmHigh 39.3°C · Low 27.2°C · 29 mm rain
- Phoenix in AugustUnited States · 58 kmHigh 39.6°C · Low 27.5°C · 29 mm rain
- Glendale (Arizona), United States in AugustUnited States · 72 kmHigh 39.6°C · Low 27.7°C · 27 mm rain
- Peoria (Arizona), United States in AugustUnited States · 79 kmHigh 39.4°C · Low 27.6°C · 27 mm rain
- Avondale in AugustUnited States · 81 kmHigh 40.2°C · Low 28.0°C · 27 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 San Tan Valley) is explained once on the San Tan Valley year overview and on the Sources, method and limits page.