Climateby Month

Fairfield, CA weather in December

NOAA 1991-2020 normals and daily records · Fairfield all year

Expect cool weather with frequent rain in Fairfield in December, with highs near 57°F and lows near 40°F. Rain falls on about 10 days. It is one of the coolest months in Fairfield.

Normal high
57°F
Normal low
40°F
Wet days
10
5.4 in total
Muggy days
0
dew point 65°F+

How December changes from start to finish

Normal values at the start and end of December
December 1December 31
Normal high60°F55°F
Normal low42°F40°F
Chance of a wet day30%33%
Sunrise / sunset7:06 am / 4:48 pm7:24 am / 4:57 pm
Daylight9.7 h9.6 h

Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Pacific Time).

A typical December day

  1. 6 am41°Fdew point 38°F
  2. 9 am45°Fdew point 41°F
  3. Noon54°Fdew point 42°F
  4. 3 pm56°Fdew point 41°F
  5. 6 pm48°Fdew point 41°F
  6. 9 pm45°Fdew point 40°F

NOAA hourly normals (local standard time) from Travis AFB (6 mi away); average wind 7 mph; clear or few clouds in 48% of daytime hours, mostly cloudy or overcast in 45%.

What kind of days to expect

  • Comfortable dayshigh 65-80°F and dew point under 60°F3 of 31
  • Hot dayshigh 90°F or more0 of 31
  • Muggy daysdaily mean dew point 65°F or more0 of 31
  • Wet daysat least 0.01 in of rain or melted snow10 of 31
  • Notable rainat least 0.10 in8 of 31
  • Freezing nightslow 32°F or below4 of 31

Average days per December, counted from daily records for each year 1991-2020.

Rain in December

Normal precipitation is 5.4 in; a dry December brings about 2.2 in and a wet one about 7.6 in (25th and 75th percentiles). About 4 days bring half an inch or more, and about 2 an inch or more. Snow is very rare.

How December varies from year to year

  • Warmest December, 1991-20202017: average high 62°F
  • Coolest December1994: average high 51°F
  • Wettest December2005: 16.7 in
  • Driest December2017: 0.03 in
  • Highest reading77°F (December 20, 1999)
  • Lowest reading15°F (December 25, 2011)

From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.

December compared with November and January

NovemberDecemberJanuary
Normal high66°F57°F57°F
Normal low45°F40°F40°F
Wet days71010
Comfortable days1634
Daylight10.1 h9.6 h9.8 h

Highs change by -9°F from November and 0°F into January.

Nearby alternatives in December

How Fairfield ranks in December

  • Normal high150th warmest of 378 cities; 48th of 60 in California
  • Wet days222nd driest of 378
  • Comfortable days156th most of 340

What to pack for Fairfield in December

  • A warm jacket – lows near 40°F, highs near 57°F
  • A rain jacket or umbrella – rain on about 10 days

Frost in December

The first fall frost typically comes around Dec 14; in 1 year in 10 it comes before Nov 29. All frost dates for Fairfield.

Heating and cooling

December has 515 heating degree days and 0 cooling degree days (base 65°F), 15% of the year's total heating and cooling demand.

Questions

How cold is Fairfield in December?

The normal high is 57°F and the normal low is 40°F. From 1991 to 2020 the coldest December reading was 15°F (December 25, 2011).

Does it rain a lot in Fairfield in December?

About 10 days in December have at least 0.01 in of precipitation, and the normal total is 5.4 in. The wettest December in 1991-2020 was in 2005 (16.7 in); the driest was in 2017 (0.03 in).

Does it snow in Fairfield in December?

Snow is very rare: the 1991-2020 normal for December rounds to 0.0 in.

Is December a good time to visit Fairfield?

December ranks 12th of 12 months on our comfort score for Fairfield (44 out of 100). It has about 3 comfortable days. The best months are April and May.

Where the numbers come from

  • Temperature, rain, snowfall, snow depth and frost dates: Fairfield (USC00042934), 2.3 mi NW of the city center, 40 ft . NOAA normals and daily records, 1991-2020.
  • Humidity and wind by hour and cloud cover: Travis AFB (USW00023202), 5.9 mi ENE of the city center, 59 ft . NOAA normals and daily records, 1991-2020.
  • Daily humidity and wind: Travis Air Force Base (745160-23202), 5.9 mi ENE of the city center, 62 ft . Hourly observations, 1991-2020.