Sun Valley climate

Sun Valley Weather in August

NOAA 1991-2020 normals for Ketchum RS, 1.6 km from Sun Valley

Average highs run from 82°F on August 1 to 75°F on August 31, and lows from 46°F to 40°F. Normal precipitation for the month is 0.50 in over about 4 wet days.

August day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at Sun Valley, in °F, with the record for each date.20406080100151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

August at a glance

Average high
79°F
Average low
44°F
Precipitation
0.50 in
Record high
99°FAug 2, 2017
Record low
37°FAug 22, 2021
Chance of a freeze
28%
Days of 90°F or more
0.9
Daylight
14 h 33 min to 13 h 14 min
Cloud cover
36%
Humidity
36%
Dew point
34°F
Wind
7.6 mph

Every day of the month

A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.

DateNormal highNormal lowRecord highRecord lowChance wetChance of snow
Aug 182°F46°F98°F 201752°F 202516%0%
Aug 282°F46°F99°F 201753°F 201616%0%
Aug 382°F46°F97°F 201746°F 201615%0%
Aug 482°F46°F95°F 201746°F 202615%0%
Aug 581°F46°F94°F 201950°F 202515%0%
Aug 681°F46°F95°F 201944°F 201815%0%
Aug 781°F46°F97°F 202646°F 202215%0%
Aug 881°F45°F97°F 202644°F 202515%0%
Aug 981°F45°F96°F 201846°F 202115%0%
Aug 1080°F45°F98°F 201839°F 201615%0%
Aug 1180°F45°F97°F 201844°F 201615%0%
Aug 1280°F45°F94°F 202546°F 201915%0%
Aug 1380°F44°F94°F 202148°F 201914%0%
Aug 1480°F44°F93°F 202147°F 201814%0%
Aug 1579°F44°F95°F 202349°F 201714%0%
Aug 1679°F44°F95°F 202346°F 201514%0%
Aug 1779°F44°F96°F 202048°F 201914%0%
Aug 1878°F43°F96°F 202244°F 202114%0%
Aug 1978°F43°F95°F 202538°F 202114%0%
Aug 2078°F43°F97°F 202641°F 202114%0%
Aug 2178°F43°F97°F 202645°F 202114%0%
Aug 2277°F42°F92°F 202537°F 202114%0%
Aug 2377°F42°F94°F 202542°F 201614%0%
Aug 2477°F42°F92°F 202541°F 201614%0%
Aug 2576°F42°F92°F 201541°F 202414%0%
Aug 2676°F41°F89°F 201744°F 202414%0%
Aug 2776°F41°F94°F 201745°F 202114%0%
Aug 2876°F41°F95°F 201739°F 202214%0%
Aug 2975°F40°F93°F 201740°F 202414%0%
Aug 3075°F40°F91°F 202242°F 202214%0%
Aug 3175°F40°F95°F 202242°F 201414%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Sun Valley, in percent, and of at least 0.1 inch of snowfall.051015201102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (MDT).

August 1
sunrise 6:27 AM, sunset 9:00 PM
August 31
sunrise 7:00 AM, sunset 8:14 PM

Every day of August: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00104845 (Ketchum RS), public domain. Records: NOAA GHCN-Daily, station USC00100774, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.