Temperature
Cold by day, freezing at night.
31°Ftypical December high
Typical range
December climate
December in Sun Valley
United States · North America
Cold conditions during longer outdoor plans are the main limitation.
Limited, but doable
Comparatively rainy.
Daytime high
31°F
Lows around 15°F
Rain
Several rainy days
Sun
7 h/day
Air feel
Very dry
When to visit
Month-by-month fit
Best
Precipitation
Several rainy days. About 10 wet days, more than in most months.
32%wet-day frequency
AmountWet-day chance
Sunshine
A mix of sunshine and cloud.
6.8 hDecember sunshine
Heat & humidity by month
Humidity is rarely noticeable in the cool air.
Very dryDecember Heat feel
Easy airWarm airHot air
Hourly temperature pattern
In December, afternoons feel about 22° and nights feel near 11°.
FrigidFreezingVery coldColdCoolComfortableNight hours
Clear sky
Mostly cloudy skies this month.
36%December Clear sky
Clear skyCloud
Wind pattern
Calm winds are typical in December.
3 mphDecember Calm
More detailIncludes daypart comfort
Typical December day
December late afternoons are around 28°F, easing to about 23°F in early evening.
Avg temp Typical range
Morning21°F
Rain20%
Cloud68%
Humid airLow
Sun intensityMinimal
Midday29°F
Rain20%
Cloud62%
Humid airLow
Sun intensityModerate
Late afternoon28°F
Rain19%
Cloud61%
Humid airLow
Sun intensityLow
Best windowEarly evening23°F
Rain19%
Cloud62%
Humid airLow
Sun intensityMinimal
Data tableView month-by-month numbers
View month-by-month numbers
| Month | High°F | Low°F | Rainin | Wet days | Sunh | Humidity% |
|---|---|---|---|---|---|---|
| Jan | 32 | 17 | 2.0 | 9 | 7.4 | 77 |
| Feb | 34 | 18 | 1.9 | 8 | 8.6 | 75 |
| Mar | 41 | 24 | 2.2 | 11 | 10.2 | 71 |
| Apr | 47 | 29 | 1.7 | 11 | 11.7 | 69 |
| May | 57 | 35 | 2.2 | 12 | 13.0 | 69 |
| Jun | 71 | 44 | 1.6 | 9 | 14.1 | 58 |
| Jul | 82 | 52 | 0.7 | 4 | 14.3 | 44 |
| Aug | 80 | 51 | 0.9 | 5 | 13.0 | 44 |
| Sep | 71 | 44 | 1.3 | 6 | 11.5 | 52 |
| Oct | 55 | 34 | 1.6 | 7 | 9.7 | 63 |
| Nov | 40 | 22 | 1.7 | 8 | 7.9 | 72 |
| Dec | 31 | 15 | 2.8 | 10 | 6.8 | 79 |
Similar climates
Similar
Similar travel styleBanffCanadaSimilar travel styleJackson HoleUnited StatesSimilar travel styleLake TahoeUnited StatesSimilar travel styleMammoth MountainUnited States
Want a side-by-side climate view? Compare Sun Valley with Banff.
Climate data notePlanning guidance, not a forecast
Typical monthly values are based on long-term climate records. Useful for planning, not a forecast. Check the weather before you travel.
Sunshine: source type is not yet identified at metric level.
Local microclimates can vary by beach, neighborhood, trail, or elevation.
Last updated: Jul 31, 2026
Data & methodology