Sun Valley, ID weather in January
Sun Valley is cold and snowy in January: highs average 31°F and nights drop to about 8°F. Expect about 10 wet days. Snowfall averages about 27.0 in. This is the depth of winter in Sun Valley. Pack for serious cold.
- Normal high
- 31°F
- Normal low
- 8°F
- Wet days
- 10
- 2.3 in total
- Snowfall
- 27.0 in
- normal snowfall
How January changes from start to finish
| January 1 | January 31 | |
|---|---|---|
| Normal high | 30°F | 33°F |
| Normal low | 8°F | 9°F |
| Chance of a wet day | 34% | 29% |
| Sunrise / sunset | 8:11 am / 5:10 pm | 7:55 am / 5:46 pm |
| Daylight | 9.0 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 (Mountain Time).
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F0 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 in6 of 31
- Freezing nightslow 32°F or below31 of 31
Average days per January, counted from daily records for each year 1991-2020.
Rain and snow in January
Normal precipitation is 2.3 in; a dry January brings about 1.0 in and a wet one about 3.1 in (25th and 75th percentiles). About 1 day brings half an inch or more. Normal snowfall is 27.0 in, with about 7 days of an inch or more.
How January varies from year to year
- Warmest January, 1991-20202014: average high 38°F
- Coolest January2017: average high 25°F
- Wettest January1995: 5.1 in
- Driest January1991: 0.2 in
- Highest reading54°F (January 27, 2015)
- Lowest reading-21°F (January 31, 1996)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
January compared with December and February
| December | January | February | |
|---|---|---|---|
| Normal high | 30°F | 31°F | 35°F |
| Normal low | 9°F | 8°F | 11°F |
| Wet days | 11 | 10 | 9 |
| Comfortable days | 0 | 0 | 0 |
| Daylight | 9.0 h | 9.4 h | 10.5 h |
Highs change by +1°F from December and +4°F into February.
Nearby alternatives in January
- Warmer: Boise, ID93 mi · high 39°F · 11 wet days
- Cooler: West Yellowstone, MT174 mi · high 23°F · 15 wet days
How Sun Valley ranks in January
- Normal high334th warmest of 378 cities; 2nd of 2 in Idaho
- Wet days189th driest of 378
- Comfortable days276th most of 339
What to pack for Sun Valley in January
- A warm jacket – lows near 8°F, highs near 31°F
- A rain jacket or umbrella – rain or snow on about 10 days
- Waterproof boots – about 27.0 in of snow in a typical year
- A hat and gloves – about 31 freezing nights
Heating and cooling
January has 1406 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 Sun Valley in January?
The normal high is 31°F and the normal low is 8°F. From 1991 to 2020 the coldest January reading was -21°F (January 31, 1996).
Does it rain a lot in Sun Valley in January?
About 10 days in January have at least 0.01 in of precipitation, and the normal total is 2.3 in. The wettest January in 1991-2020 was in 1995 (5.1 in); the driest was in 1991 (0.2 in).
Does it snow in Sun Valley in January?
Yes. Normal snowfall in January is 27.0 in.
Where the numbers come from
- Temperature, rain and snowfall: Ketchum RS (USC00104845), 1.0 mi SSW of the city center, 5,890 ft (62 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Frost dates: Bellevue (USC00100774), 17 mi SSE of the city center, 5,192 ft (760 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Stanley Ranger Station (726824-04112), 44 mi NW of the city center, 6,495 ft (543 ft higher than the city). Hourly observations, 1991-2020.
- Not available for this location: snow depth, humidity and wind by hour and cloud cover (no station close enough or similar enough in elevation).