Temperature
Cool by day, cold at night.
57°Ftypical May high
Typical range
Cool days and plenty of sun.
Cool by day, cold at night.
Several rainy days. About 12 wet days, the highest monthly average.
Plenty of sun this month.
In May, afternoons feel about 48° and nights feel near 31°.
Partly cloudy skies this month.
Calm winds are typical in May.
May late afternoons are around 55°F, easing to about 50°F in early evening.
| 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
Want a side-by-side climate view? Compare Sun Valley with Banff.
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