Climate averages 1991–2020
Modesto weather
in December.
A cool, moderately wet month: the coolest and the 11th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
December is a cool month in Modesto: daytime highs average 13.7°C and nights cool to about 5.0°C. By daytime temperature it is the coolest month of the year.
Expect about 86 mm of rain on roughly 8 days, which makes December a moderately wet month (the 11th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 9 h 37 min on an average December day.
The nearest other city in this atlas is Turlock (21 km away). In December its highs average 13.9°C, about as warm as Modesto, with 76 mm of rain.
Among the 498 cities listed in the United States, Modesto ranks joint 183rd of 498 for the warmest December highs and joint 304th of 498 for the driest December (rainfall, lowest first). The mean December high of those 498 cities is 10.5°C; Modesto is 3.2°C warmer than that mean.
From December to January, average highs rise by 0.3°C to 14.0°C, and monthly rainfall rises from 86 mm to 92 mm.
The annual picture
December 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
Modesto climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 14.0°C4.9°C | 4.9°C | 92 | 8.4 | 9.910 h |
| February | 15.8°C6.1°C | 6.1°C | 85 | 8.8 | 10.811 h |
| March | 18.7°C7.7°C | 7.7°C | 72 | 8.3 | 11.912 h |
| April | 22.1°C9.6°C | 9.6°C | 36 | 4.7 | 13.113 h |
| May | 27.4°C12.9°C | 12.9°C | 20 | 3.0 | 14.214 h |
| June | 32.3°C16.0°C | 16.0°C | 3.6 | 0.8 | 14.715 h |
| July | 35.1°C18.2°C | 18.2°C | 0.2 | 0.0 | 14.514 h |
| August | 34.1°C17.7°C | 17.7°C | 0.8 | 0.2 | 13.614 h |
| September | 31.3°C16.3°C | 16.3°C | 1.9 | 0.6 | 12.512 h |
| October | 25.5°C12.8°C | 12.8°C | 22 | 2.6 | 11.311 h |
| November | 18.3°C8.1°C | 8.1°C | 45 | 5.5 | 10.210 h |
| December, selected | 13.7°C5.0°C | 5.0°C | 86 | 8.3 | 9.610 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
December in nearby cities
- Turlock in DecemberUnited States · 21 kmHigh 13.9°C · Low 5.0°C · 76 mm rain
- Manteca in DecemberUnited States · 26 kmHigh 13.5°C · Low 4.7°C · 74 mm rain
- Tracy in DecemberUnited States · 39 kmHigh 14.0°C · Low 5.0°C · 76 mm rain
- Stockton in DecemberUnited States · 44 kmHigh 13.5°C · Low 4.8°C · 93 mm rain
- Merced in DecemberUnited States · 59 kmHigh 13.9°C · Low 4.4°C · 75 mm rain
- Livermore in DecemberUnited States · 68 kmHigh 13.6°C · Low 5.5°C · 79 mm rain
- Pleasanton in DecemberUnited States · 77 kmHigh 13.9°C · Low 5.8°C · 79 mm rain
- Antioch in DecemberUnited States · 82 kmHigh 13.7°C · Low 6.3°C · 87 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 Modesto) is explained once on the Modesto year overview and on the Sources, method and limits page.