Idaho Falls weather in December: Idaho Falls, Idaho: normal highs, lows, rain and records for December
Idaho Falls in December has a normal high of 30°F and a normal low of 13°F, a daily mean of 22°F, falling from 35°F on the 1st to 28°F by the 31st. Measurable precipitation falls on 10 days in a normal December, 0.78 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of −1°C and low of −10°C, 20 mm of precipitation in December.
- NOAA stationIdaho Falls Fanning Field
- Station IDUSW00024145
- Location43.52°N 112.07°W
- Elevation4,729 ft (1,441 m)
- Population69,523
- Jan 29° 12°
- Feb 34° 16°
- Mar 47° 25°
- Apr 58° 31°
- May 67° 38°
- Jun 76° 45°
- Jul 87° 49°
- Aug 86° 48°
- Sep 75° 41°
- Oct 59° 31°
- Nov 43° 22°
- Dec 30° 13°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Idaho Falls in December?
The normal high is 30°F and the normal low 13°F, for a daily mean of 21.9°F. December is 10.5°F cooler than November and 1.5°F warmer than January. December is the 11th warmest month of the year in Idaho Falls and the 7th wettest. Across the month the normal high falls 7°F, from 35°F on December 1 to 28°F on December 31. From one year to the next December's mean temperature typically moves about 3.9°F either way (NOAA's standard deviation), so roughly two Decembers in three average between 18°F and 26°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 30%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| December 1 | 35°F | 17°F | 28% | 7% |
| December 8 | 32°F | 15°F | 29% | 7% |
| December 15 | 30°F | 13°F | 30% | 7% |
| December 22 | 29°F | 12°F | 30% | 7% |
| December 31 | 28°F | 11°F | 29% | 8% |
Every day of December: normal high, low and chance of precipitation (warmest afternoon December 1, coldest night December 30)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| December 1 | 35°F | 17°F | 28% | 7% | 9 h 10 min |
| December 2 | 35°F | 17°F | 28% | 7% | 9 h 10 min |
| December 3 | 34°F | 17°F | 28% | 7% | 9 h 10 min |
| December 4 | 34°F | 16°F | 28% | 7% | 9 h 10 min |
| December 5 | 33°F | 16°F | 29% | 7% | 9 h 10 min |
| December 6 | 33°F | 16°F | 29% | 7% | 9 h 10 min |
| December 7 | 33°F | 15°F | 29% | 7% | 9 h 10 min |
| December 8 | 32°F | 15°F | 29% | 7% | 9 h |
| December 9 | 32°F | 15°F | 29% | 7% | 9 h |
| December 10 | 31°F | 14°F | 30% | 7% | 9 h |
| December 11 | 31°F | 14°F | 30% | 7% | 9 h |
| December 12 | 31°F | 14°F | 30% | 7% | 9 h |
| December 13 | 30°F | 14°F | 30% | 7% | 9 h |
| December 14 | 30°F | 13°F | 30% | 7% | 9 h |
| December 15 | 30°F | 13°F | 30% | 7% | 9 h |
| December 16 | 30°F | 13°F | 30% | 7% | 9 h |
| December 17 | 29°F | 13°F | 30% | 7% | 9 h |
| December 18 | 29°F | 13°F | 30% | 7% | 9 h |
| December 19 | 29°F | 12°F | 30% | 7% | 9 h |
| December 20 | 29°F | 12°F | 30% | 7% | 9 h |
| December 21 | 29°F | 12°F | 30% | 7% | 9 h |
| December 22 | 29°F | 12°F | 30% | 7% | 9 h |
| December 23 | 28°F | 12°F | 30% | 7% | 9 h |
| December 24 | 28°F | 12°F | 30% | 7% | 9 h |
| December 25 | 28°F | 12°F | 30% | 7% | 9 h |
| December 26 | 28°F | 12°F | 30% | 8% | 9 h |
| December 27 | 28°F | 11°F | 30% | 8% | 9 h |
| December 28 | 28°F | 11°F | 30% | 8% | 9 h |
| December 29 | 28°F | 11°F | 29% | 8% | 9 h |
| December 30 | 28°F | 11°F | 29% | 8% | 9 h |
| December 31 | 28°F | 11°F | 29% | 8% | 9 h |
- Normal high
- 30°FDecember average
- Normal low
- 13°FDecember average
- Precipitation
- 0.78 inmonth total
- Days with precipitation
- 100.01 inch or more
- Nights at 32°F or colder
- 30
- Daylight
- 9 h 10 min to 9 hDecember 1 to December 31
- Sunshine
- 60%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00024145; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Idaho Falls in December?
On a given December day the chance of 0.01 inch or more is 30% on average, highest around December 14 (30%). In all, 0.78 in falls on 10 days of a normal December.
In a normal December in Idaho Falls, 30 nights fall to freezing and 18 days stay below freezing all day.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00024145.
What are the records for December in Idaho Falls?
The warmest December temperature on this station's record (since 1948) is 58°F, on December 12, 2014; the coldest is −31°F, on December 5, 1972. The wettest December brought 2.07 in (2025); the snowiest, 27.9 inches (1983).
The December mean against the 1991-2020 normal of 21.9°F: 2021 28.6°F (+6.7), 2022 18.8°F (−3.1), 2023 28.7°F (+6.8), 2024 29.8°F (+7.9), 2025 34.5°F (+12.6). 4 of 5 ran warmer than normal.
| December | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 28.6°F | +6.7°F | 0.81 in |
| 2022 | 18.8°F | −3.1°F | 0.87 in |
| 2023 | 28.7°F | +6.8°F | 0.22 in |
| 2024 | 29.8°F | +7.9°F | 0.88 in |
| 2025 | 34.5°F | +12.6°F | 2.07 in |
Source: records: ACIS, station USW00024145; recent months: ACIS, station USW00024145. Records and recent months use complete months only.
How does December in Idaho Falls compare across Idaho?
Across the 85 places PlainClimate covers in Idaho, December normal highs run from 26°F in Island Park to 44°F in Glenns Ferry; Idaho Falls's is 30°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.
Other months and places
- Idaho Falls in November43°F by day, 22°F at night
- Idaho Falls in January29°F by day, 12°F at night
- Idaho Falls through the yearEvery month, frost dates, records and recent years
- Idaho in DecemberThe statewide normal and the warmest and coolest places
- Glenns Ferry: Idaho's warmest Decembernormal high 44°F