Pomona, CA weather in December
In December, Pomona sees highs around 67°F and lows around 44°F: mild and mostly dry. Rain falls on about 6 days. It is one of the coolest months in Pomona. Good for outdoor plans.
- Normal high
- 67°F
- Normal low
- 44°F
- Wet days
- 6
- 3.3 in total
- Daylight
- 9.9 h
How December changes from start to finish
| December 1 | December 31 | |
|---|---|---|
| Normal high | 69°F | 67°F |
| Normal low | 45°F | 44°F |
| Chance of a wet day | 17% | 21% |
| Sunrise / sunset | 6:38 am / 4:41 pm | 6:56 am / 4:51 pm |
| Daylight | 10.1 h | 9.9 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
- 6 am47°Fdew point 33°F
- 9 am54°Fdew point 34°F
- Noon63°Fdew point 32°F
- 3 pm65°Fdew point 33°F
- 6 pm59°Fdew point 37°F
- 9 pm54°Fdew point 36°F
NOAA hourly normals (local standard time) from Burbank Glendale Pasadena Airport (36 mi away); average wind 4 mph; clear or few clouds in 77% of daytime hours, mostly cloudy or overcast in 20%.
What kind of days to expect
- Comfortable dayshigh 65-80°F (temperature only: no humidity station nearby)15 of 31
- Hot dayshigh 90°F or more0 of 31
- Wet daysat least 0.01 in of rain or melted snow6 of 31
- Notable rainat least 0.10 in4 of 31
- Freezing nightslow 32°F or below1 of 31
Average days per December, counted from daily records for each year 1991-2020.
Rain in December
Normal precipitation is 3.3 in; a dry December brings about 0.9 in and a wet one about 5.1 in (25th and 75th percentiles). About 2 days bring half an inch or more, and about 1 an inch or more. Snow is very rare.
How December varies from year to year
- Warmest December, 1991-20202017: average high 75°F
- Coolest December2001: average high 63°F
- Wettest December2010: 16.2 in
- Driest December1999: no measurable precipitation
- Highest reading86°F (December 24, 2005)
- Lowest reading28°F (December 23, 1998)
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
| November | December | January | |
|---|---|---|---|
| Normal high | 75°F | 67°F | 68°F |
| Normal low | 49°F | 44°F | 45°F |
| Wet days | 4 | 6 | 7 |
| Comfortable days | 18 | 15 | 16 |
| Daylight | 10.4 h | 9.9 h | 10.2 h |
Highs change by -8°F from November and +1°F into January.
Nearby alternatives in December
- Drier: Palm Springs, CA71 mi · high 69°F · 2 wet days
- Cooler: Palmdale, CA42 mi · high 58°F · 4 wet days
How Pomona ranks in December
- Normal high51st warmest of 378 cities; 16th of 60 in California
- Wet days72nd driest of 378
Frost in December
The first fall frost typically comes around Dec 28; in 1 year in 10 it comes before Dec 5. All frost dates for Pomona.
Heating and cooling
December has 304 heating degree days and 2 cooling degree days (base 65°F), 9% of the year's total heating and cooling demand.
Questions
How cold is Pomona in December?
The normal high is 67°F and the normal low is 44°F. From 1991 to 2020 the coldest December reading was 28°F (most recently on December 23, 1998).
Does it rain a lot in Pomona in December?
About 6 days in December have at least 0.01 in of precipitation, and the normal total is 3.3 in. The wettest December in 1991-2020 was in 2010 (16.2 in); the driest was in 1999, with no measurable precipitation.
Is December a good time to visit Pomona?
December ranks 6th of 12 months on our comfort score for Pomona (64 out of 100). It has about 15 comfortable days (judged by temperature only). The best months are March, April and May.
Where the numbers come from
- Temperature: Ontario Intl Airport (USW00003102), 8.7 mi E of the city center, 949 ft (100 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Rain: San Gabriel Canyon PH (USC00047776), 11 mi NW of the city center, 744 ft (105 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Snowfall and snow depth: Covina City Yard Fc387b (USC00042090), 7.7 mi WNW of the city center, 607 ft (242 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Frost dates: Pomona/Fairplex (USC00047050), 2.0 mi NNW of the city center, 999 ft (150 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Humidity and wind by hour and cloud cover: Burbank Glendale Pasadena Airport (USW00023152), 36 mi WNW of the city center, 741 ft (108 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Not available for this location: daily humidity and wind (no station close enough or similar enough in elevation).