Casper, WY weather in August
Casper is warm and mostly dry in August: highs average 87°F and nights drop to about 51°F. Rain falls on about 6 days. This is the peak of the warm season in Casper.
- Normal high
- 87°F
- Normal low
- 51°F
- Wet days
- 6
- 0.8 in total
- Muggy days
- 0
- dew point 65°F+
How August changes from start to finish
| August 1 | August 31 | |
|---|---|---|
| Normal high | 90°F | 83°F |
| Normal low | 55°F | 47°F |
| Chance of a wet day | 21% | 19% |
| Sunrise / sunset | 5:56 am / 8:26 pm | 6:28 am / 7:42 pm |
| Daylight | 14.5 h | 13.2 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Mountain Time).
A typical August day
- 6 am56°Fdew point 44°F
- 9 am72°Fdew point 44°F
- Noon81°Fdew point 41°F
- 3 pm84°Fdew point 38°F
- 6 pm79°Fdew point 39°F
- 9 pm67°Fdew point 43°F
NOAA hourly normals (local standard time) from Casper Natrona Co Airport (8 mi away); average wind 9 mph; clear or few clouds in 83% of daytime hours, mostly cloudy or overcast in 11%.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F4 of 31
- Hot dayshigh 90°F or more13 of 31
- Muggy daysdaily mean dew point 65°F or more0 of 31
- Wet daysat least 0.01 in of rain or melted snow6 of 31
- Notable rainat least 0.10 in2 of 31
- Freezing nightslow 32°F or below0 of 31
- Snow on the groundsnow depth 1 in or more0 of 31
Average days per August, counted from daily records for each year 1991-2020.
Rain in August
Normal precipitation is 0.8 in; a dry August brings about 0.3 in and a wet one about 1.1 in (25th and 75th percentiles). Days with half an inch or more are rare.
How August varies from year to year
- Warmest August, 1991-20201995: average high 91°F
- Coolest August2004: average high 82°F
- Wettest August2007: 2.6 in
- Driest August1995: 0.04 in
- Highest reading101°F (August 6, 2001)
- Lowest reading29°F (August 23, 2015)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
August compared with July and September
| July | August | September | |
|---|---|---|---|
| Normal high | 89°F | 87°F | 76°F |
| Normal low | 53°F | 51°F | 42°F |
| Wet days | 7 | 6 | 7 |
| Comfortable days | 3 | 4 | 14 |
| Daylight | 15.0 h | 13.9 h | 12.5 h |
Highs change by -2°F from July and -11°F into September.
Nearby alternatives in August
- Cooler: Keystone, SD162 mi · high 78°F · 9 wet days
How Casper ranks in August
- Normal high180th warmest of 378 cities; 1st of 4 in Wyoming
- Wet days114th driest of 378
- Comfortable days144th most of 341
What to pack for Casper in August
- Light, breathable clothing – highs near 87°F
- Layers – afternoons near 87°F but nights near 51°F
Heating and cooling
August has 31 heating degree days and 157 cooling degree days (base 65°F), 2% of the year's total heating and cooling demand.
Questions
How hot is Casper in August?
The normal high is 87°F and the normal low is 51°F. From 1991 to 2020 the hottest August reading was 101°F (August 6, 2001).
Does it rain a lot in Casper in August?
About 6 days in August have at least 0.01 in of precipitation, and the normal total is 0.8 in. The wettest August in 1991-2020 was in 2007 (2.6 in); the driest was in 1995 (0.04 in).
Is August a good time to visit Casper?
August ranks 6th of 12 months on our comfort score for Casper (53 out of 100). It has about 4 comfortable days and about 13 days at 90°F or hotter. The best month is May.
Where the numbers come from
- Temperature, rain, snowfall, snow depth, frost dates, humidity and wind by hour and cloud cover: Casper Natrona Co Airport (USW00024089), 7.9 mi WNW of the city center, 5,338 ft (233 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Natrona County International Airport (725690-24089), 8.4 mi WNW of the city center, 5,319 ft (214 ft higher than the city). Hourly observations, 1991-2020.