Home › Cities › United States › Idaho › Sun Valley
Sun Valley, Idaho climate
Dsb Mediterranean-influenced warm-summer humid continental
Sun Valley has a seasonal cold-temperate climate (Mediterranean-influenced warm-summer humid continental, Köppen Dsb). The hottest month is July with an average daily high near 27°C, while the coldest is January averaging around −14°C at night. Precipitation totals about 429 mm a year and is strongly seasonal — December alone averages 69 mm while August barely receives 11 mm. Snowfall is heavy (261 cm of snow per year on average).
Temperature & precipitation
Daily high–low temperature range with the monthly average, plus monthly precipitation split into rain and snow · 1991–2020 normals · hover a month for the exact figuresHours of sunshine per day
Estimated sunny hours each month — daylight length × clear-sky fraction · 1991–2020 monthly cloud cover (NASA POWER)Sun Valley climate normals (1991–2020)
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 0 | 2 | 6 | 12 | 17 | 21 | 27 | 26 | 21 | 14 | 6 | 0 |
| Avg temp (°C) | −7 | −5 | −1 | 4 | 9 | 13 | 17 | 16 | 12 | 5 | −1 | −7 |
| Avg low (°C) | −14 | −12 | −8 | −3 | 1 | 4 | 7 | 6 | 2 | −3 | −8 | −13 |
| Precipitation (mm) | 54 | 42 | 45 | 30 | 42 | 36 | 12 | 11 | 20 | 36 | 30 | 69 |
| Snowfall (cm) | 72 | 47 | 27 | 9 | 0 | — | — | — | 0 | 4 | 26 | 75 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Avg high (°C) | 0 | 2 | 6 | 12 | 17 | 21 |
| Avg temp (°C) | −7 | −5 | −1 | 4 | 9 | 13 |
| Avg low (°C) | −14 | −12 | −8 | −3 | 1 | 4 |
| Precipitation (mm) | 54 | 42 | 45 | 30 | 42 | 36 |
| Snowfall (cm) | 72 | 47 | 27 | 9 | 0 | — |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Avg high (°C) | 27 | 26 | 21 | 14 | 6 | 0 |
| Avg temp (°C) | 17 | 16 | 12 | 5 | −1 | −7 |
| Avg low (°C) | 7 | 6 | 2 | −3 | −8 | −13 |
| Precipitation (mm) | 12 | 11 | 20 | 36 | 30 | 69 |
| Snowfall (cm) | — | — | 0 | 4 | 26 | 75 |
How often — frequency of weather events
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Days with measurable rain (days) | 9 | 8 | 8 | 6 | 7 | 7 | 4 | 4 | 4 | 5 | 6 | 10 |
| Days with high ≥ 32°C (days) | — | — | — | — | — | 0.2 | 2 | 0.9 | 0.0 | — | — | — |
| Days with low ≤ 0°C (days) | 31 | 27 | 30 | 24 | 12 | 4 | 1 | 1 | 8 | 23 | 28 | 30 |
| Days with snowfall ≥ 2.5 cm (days) | 7 | 5 | 3 | 1 | 0.1 | — | — | — | — | 0.5 | 3 | 8 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Days with measurable rain (days) | 9 | 8 | 8 | 6 | 7 | 7 |
| Days with high ≥ 32°C (days) | — | — | — | — | — | 0.2 |
| Days with low ≤ 0°C (days) | 31 | 27 | 30 | 24 | 12 | 4 |
| Days with snowfall ≥ 2.5 cm (days) | 7 | 5 | 3 | 1 | 0.1 | — |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Days with measurable rain (days) | 4 | 4 | 4 | 5 | 6 | 10 |
| Days with high ≥ 32°C (days) | 2 | 0.9 | 0.0 | — | — | — |
| Days with low ≤ 0°C (days) | 1 | 1 | 8 | 23 | 28 | 30 |
| Days with snowfall ≥ 2.5 cm (days) | — | — | — | 0.5 | 3 | 8 |
Sky & atmosphere
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cloud cover (%) | 59 | 61 | 64 | 63 | 61 | 50 | 35 | 35 | 39 | 48 | 58 | 61 |
| Relative humidity (%) | 84 | 82 | 74 | 64 | 58 | 51 | 39 | 36 | 41 | 54 | 70 | 83 |
| Wind speed (km/h) | 5.9 | 6.7 | 7.6 | 8.0 | 7.8 | 7.8 | 7.5 | 7.3 | 6.8 | 6.7 | 6.1 | 5.9 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Cloud cover (%) | 59 | 61 | 64 | 63 | 61 | 50 |
| Relative humidity (%) | 84 | 82 | 74 | 64 | 58 | 51 |
| Wind speed (km/h) | 5.9 | 6.7 | 7.6 | 8.0 | 7.8 | 7.8 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Cloud cover (%) | 35 | 35 | 39 | 48 | 58 | 61 |
| Relative humidity (%) | 39 | 36 | 41 | 54 | 70 | 83 |
| Wind speed (km/h) | 7.5 | 7.3 | 6.8 | 6.7 | 6.1 | 5.9 |
Methodology & sources
Temperature & precipitation — 1991–2020 normals computed from 29 years of daily observations at Ketchum RS, a weather station, about 2 km from the city centre. The underlying daily records come from NOAA's global station network.
Cloud, humidity, wind & sunshine — modelled estimates from NASA POWER, NASA's satellite-and-reanalysis climatology. This is the standard global source for atmospheric variables, which are not measured at most weather stations.