Sun Valley (ID) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Sun Valley.
Climate overview of Sun Valley
Temperatures in Sun Valley, Idaho, United States of America, vary greatly throughout the year. July is the hottest month at 27°C (81°F), while December is the coldest at 0°C (32°F).
The city has a relatively dry climate, receiving around 451 mm (18 in) of rain/snowfall per year. It does experience a distinct dry season from April to September, with warm summers and very cold winters. December is the wettest month and July the driest.
Sun Valley Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Sun Valley - and find the best time to visit.
Monthly Temperature in Sun Valley
The climate in Sun Valley is known for significant temperature differences throughout the year, making the weather dynamic. On average, daytime temperatures range from a comfortable 27°C (81°F) in July to a very cold 0°C (32°F) in December.
Nighttime temperatures range from 8°C (46°F) in July to -12°C (10°F) in December.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Sun Valley
Sun Valley has a relatively dry climate with low precipitation, averaging 451 mm (18 in) of rain/snowfall annually. The seasons in Sun Valley bring significant changes in precipitation. The wettest month, December, receives moderate snowfall, with an average of 80 mm (3.1 in) of precipitation. This snowfall is distributed across 15 snowy days.
In contrast, the driest month, July, experiences much less rainfall, totaling 11 mm (0.4 in) over 5 rainy days. These distinct seasonal differences provide diverse experiences throughout the year. For more details, please visit our Sun Valley Precipitation page.
The mean monthly precipitation over the year, including rain, hail, and snow
The average number of days each month with precipitation
Best Time to Visit Sun Valley
Each month is rated for comfortable sightseeing weather — mild temperatures and low rainfall. Tap a month for its full averages; your ideal time may differ for a beach or winter trip (see below).
- Best overall: June, July, August and September
- Warmest weather: July and August
- Fewest rainy days: July, August and September
- Climate seasons: a distinct dry season from April to September, with warm summers and very cold winters
- Best for winter weather: December, with freezing nights around -12°C (10°F).
Frequently asked questions about the climate in Sun Valley
What is the best time to visit Sun Valley?
June, July, August and September typically offer the most optimal weather in Sun Valley. In contrast, January, February, March, November and December tend to have less optimal conditions. Sun Valley has a distinct dry season from April to September, with warm summers and very cold winters.
What temperatures can I expect in Sun Valley?
Daytime highs range from 0°C (32°F) in December to 27°C (81°F) in July. Nighttime lows range from -12°C (10°F) to 8°C (46°F). Temperatures vary considerably through the year.
How much rain does Sun Valley get?
Annual rainfall is around 451 mm (18 in). December is the wettest month with 80 mm (3.1 in), while July is the driest with 11 mm (0.4 in). In the coldest months, precipitation may fall as snow.
Sun Valley 3-Day Forecast
Sun Valley (ID) 3-Day Forecast
Sun Valley on the map
Sun Valley is highlighted - select any city to see its climate.
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