Climate averages 1991–2020
Merced weather
in December.
A cool, moderately wet month: the coolest and the 10th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
December is a cool month in Merced: daytime highs average 13.9°C and nights cool to about 4.4°C. By daytime temperature it is the coolest month of the year.
Expect about 75 mm of rain on roughly 7 days, which makes December a moderately wet month (the 10th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 9 h 39 min on an average December day.
The nearest other city in this atlas is Turlock (39 km away). In December its highs average 13.9°C, about as warm as Merced, with 76 mm of rain.
Among the 498 cities listed in the United States, Merced ranks joint 171st of 498 for the warmest December highs and joint 264th of 498 for the driest December (rainfall, lowest first). The mean December high of those 498 cities is 10.5°C; Merced is 3.4°C warmer than that mean.
From December to January, average highs rise by 0.3°C to 14.2°C, and monthly rainfall rises from 75 mm to 90 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
Merced climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 14.2°C4.3°C | 4.3°C | 90 | 8.1 | 9.910 h |
| February | 16.0°C5.6°C | 5.6°C | 80 | 8.5 | 10.811 h |
| March | 18.9°C7.6°C | 7.6°C | 71 | 7.7 | 11.912 h |
| April | 22.5°C9.9°C | 9.9°C | 32 | 4.7 | 13.113 h |
| May | 27.8°C13.7°C | 13.7°C | 19 | 2.8 | 14.114 h |
| June | 32.9°C17.3°C | 17.3°C | 3.6 | 0.6 | 14.715 h |
| July | 36.2°C20.2°C | 20.2°C | 0.6 | 0.2 | 14.514 h |
| August | 35.3°C19.6°C | 19.6°C | 0.6 | 0.1 | 13.614 h |
| September | 32.2°C17.3°C | 17.3°C | 1.7 | 0.4 | 12.512 h |
| October | 26.0°C12.7°C | 12.7°C | 21 | 2.3 | 11.311 h |
| November | 18.7°C7.6°C | 7.6°C | 37 | 4.8 | 10.210 h |
| December, selected | 13.9°C4.4°C | 4.4°C | 75 | 7.4 | 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 · 39 kmHigh 13.9°C · Low 5.0°C · 76 mm rain
- Modesto in DecemberUnited States · 59 kmHigh 13.7°C · Low 5.0°C · 86 mm rain
- Manteca in DecemberUnited States · 85 kmHigh 13.5°C · Low 4.7°C · 74 mm rain
- Clovis in DecemberUnited States · 87 kmHigh 14.0°C · Low 3.8°C · 71 mm rain
- Fresno in DecemberUnited States · 88 kmHigh 14.2°C · Low 4.3°C · 71 mm rain
- Tracy in DecemberUnited States · 96 kmHigh 14.0°C · Low 5.0°C · 76 mm rain
- Stockton in DecemberUnited States · 102 kmHigh 13.5°C · Low 4.8°C · 93 mm rain
- Livermore in DecemberUnited States · 121 kmHigh 13.6°C · Low 5.5°C · 79 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 Merced) is explained once on the Merced year overview and on the Sources, method and limits page.