Ada County Weather in December
Average highs run from 42°F on December 1 to 37°F on December 31, and lows from 28°F to 24°F. Normal precipitation for the month is 1.54 in over about 12 wet days.
December day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
December at a glance
- Average high
- 39°F
- Average low
- 25°F
- Precipitation
- 1.54 in
- Snowfall
- 5.6 in
- Record high
- 65°FDec 22, 1964
- Record low
- -25°FDec 22, 1990
- Chance of a freeze
- 100%
- Daylight
- 9 h 12 min to 9 h 01 min
- Cloud cover
- 65%
- Humidity
- 79%
- Dew point
- 23°F
- Wind
- 7.4 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| Dec 1 | 42°F | 28°F | 60°F 1941 | 9°F 1948 | 36% | 14% |
| Dec 2 | 42°F | 28°F | 62°F 2012 | 9°F 1983 | 36% | 14% |
| Dec 3 | 41°F | 27°F | 61°F 2007 | 15°F 1992 | 36% | 14% |
| Dec 4 | 41°F | 27°F | 60°F 2007 | 4°F 1983 | 37% | 15% |
| Dec 5 | 41°F | 27°F | 61°F 2023 | -6°F 1972 | 37% | 15% |
| Dec 6 | 41°F | 27°F | 63°F 1987 | 0°F 1992 | 37% | 15% |
| Dec 7 | 40°F | 27°F | 54°F 1981 | 0°F 1972 | 37% | 15% |
| Dec 8 | 40°F | 26°F | 60°F 1993 | -19°F 1972 | 37% | 16% |
| Dec 9 | 40°F | 26°F | 57°F 1993 | -21°F 1972 | 37% | 16% |
| Dec 10 | 39°F | 26°F | 62°F 2025 | -23°F 1972 | 37% | 16% |
| Dec 11 | 39°F | 26°F | 63°F 2014 | -22°F 1972 | 37% | 16% |
| Dec 12 | 39°F | 26°F | 62°F 2014 | -9°F 1972 | 37% | 17% |
| Dec 13 | 39°F | 25°F | 54°F 1969 | -14°F 1972 | 37% | 17% |
| Dec 14 | 39°F | 25°F | 58°F 2002 | -9°F 1972 | 38% | 17% |
| Dec 15 | 38°F | 25°F | 55°F 1968 | -7°F 1972 | 38% | 17% |
| Dec 16 | 38°F | 25°F | 59°F 1941 | -2°F 1985 | 38% | 17% |
| Dec 17 | 38°F | 25°F | 58°F 2025 | -2°F 1985 | 38% | 18% |
| Dec 18 | 38°F | 25°F | 59°F 2024 | -3°F 1985 | 38% | 18% |
| Dec 19 | 38°F | 25°F | 58°F 2025 | -6°F 1984 | 38% | 18% |
| Dec 20 | 38°F | 25°F | 57°F 1964 | -8°F 1990 | 38% | 18% |
| Dec 21 | 38°F | 25°F | 60°F 1964 | -23°F 1990 | 38% | 18% |
| Dec 22 | 38°F | 25°F | 65°F 1964 | -25°F 1990 | 38% | 18% |
| Dec 23 | 38°F | 24°F | 61°F 2025 | -18°F 1983 | 38% | 18% |
| Dec 24 | 38°F | 24°F | 60°F 2025 | -20°F 1990 | 38% | 19% |
| Dec 25 | 37°F | 24°F | 59°F 2025 | -20°F 1990 | 38% | 19% |
| Dec 26 | 37°F | 24°F | 57°F 1976 | -8°F 1985 | 38% | 19% |
| Dec 27 | 37°F | 24°F | 56°F 2022 | -7°F 1985 | 38% | 19% |
| Dec 28 | 37°F | 24°F | 59°F 1945 | -9°F 1985 | 38% | 19% |
| Dec 29 | 37°F | 24°F | 56°F 1996 | -17°F 1990 | 38% | 19% |
| Dec 30 | 37°F | 24°F | 54°F 1996 | -9°F 1990 | 38% | 19% |
| Dec 31 | 37°F | 24°F | 58°F 1996 | -9°F 1978 | 38% | 19% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (MST).
- December 1
- sunrise 7:58 AM, sunset 5:10 PM
- December 31
- sunrise 8:18 AM, sunset 5:19 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USW00024131 (Boise Air Terminal), public domain. Records: NOAA GHCN-Daily, station USW00024131, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.