Climate averages 1991–2020
San Tan Valley weather
in January.
A mild, fairly dry month: the 11th 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 San Tan Valley: daytime highs average 18.2°C and nights cool to about 4.9°C. By daytime temperature it is the 11th warmest of the 12 months.
Expect about 38 mm of rain on roughly 4 days, which makes January a fairly dry month (the 11th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 10 h 13 min on an average January day.
The nearest other city in this atlas is Chandler (32 km away). In January its highs average 18.8°C, 0.6°C warmer than San Tan Valley, with 32 mm of rain.
Among the 498 cities listed in the United States, San Tan Valley ranks joint 68th of 498 for the warmest January highs and joint 85th of 498 for the driest January (rainfall, lowest first). The mean January high of those 498 cities is 9.5°C; San Tan Valley is 8.8°C warmer than that mean.
From January to February, average highs rise by 1.6°C to 19.8°C, and monthly rainfall rises from 38 mm to 41 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
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, selected | 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 | 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
January in nearby cities
- Chandler in JanuaryUnited States · 32 kmHigh 18.8°C · Low 4.6°C · 32 mm rain
- Mesa in JanuaryUnited States · 38 kmHigh 18.5°C · Low 4.3°C · 40 mm rain
- Tempe in JanuaryUnited States · 43 kmHigh 18.6°C · Low 4.4°C · 32 mm rain
- Scottsdale in JanuaryUnited States · 49 kmHigh 18.4°C · Low 4.7°C · 32 mm rain
- Phoenix in JanuaryUnited States · 58 kmHigh 18.6°C · Low 4.6°C · 32 mm rain
- Glendale (Arizona), United States in JanuaryUnited States · 72 kmHigh 18.5°C · Low 4.9°C · 28 mm rain
- Peoria (Arizona), United States in JanuaryUnited States · 79 kmHigh 18.4°C · Low 5.1°C · 28 mm rain
- Avondale in JanuaryUnited States · 81 kmHigh 19.0°C · Low 5.0°C · 28 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.