Climateby Month

Cheyenne vs Casper weather

Cheyenne, WY and Casper, WY · 142 mi apart

July highs: 84°F in Cheyenne, 89°F in Casper (Casper is 5°F warmer). January highs: 40°F and 35°F (Cheyenne is 5°F warmer). Cheyenne has about 101 wet days a year, Casper about 91. Snow: 62.9 in a year in Cheyenne, 71.8 in in Casper.

Cheyenne, WY

0°20°40°60°80°100° January: normal high 40°F (4°C), low 18°F (-8°C) February: normal high 41°F (5°C), low 18°F (-8°C) March: normal high 49°F (9°C), low 25°F (-4°C) April: normal high 55°F (13°C), low 31°F (-1°C) May: normal high 64°F (18°C), low 40°F (4°C) June: normal high 77°F (25°C), low 49°F (9°C) July: normal high 84°F (29°C), low 56°F (13°C) 84° 56° August: normal high 82°F (28°C), low 54°F (12°C) September: normal high 73°F (23°C), low 46°F (8°C) October: normal high 59°F (15°C), low 34°F (1°C) November: normal high 48°F (9°C), low 25°F (-4°C) December: normal high 39°F (4°C), low 18°F (-8°C) 39° 18° JFMAMJJASOND

Best months: May, June

Casper, WY

0°20°40°60°80°100° January: normal high 35°F (2°C), low 15°F (-9°C) 35° 15° February: normal high 38°F (3°C), low 15°F (-9°C) March: normal high 49°F (9°C), low 23°F (-5°C) April: normal high 56°F (13°C), low 28°F (-2°C) May: normal high 67°F (19°C), low 37°F (3°C) June: normal high 80°F (27°C), low 45°F (7°C) July: normal high 89°F (32°C), low 53°F (12°C) 89° 53° August: normal high 87°F (31°C), low 51°F (11°C) September: normal high 76°F (24°C), low 42°F (6°C) October: normal high 60°F (16°C), low 31°F (-1°C) November: normal high 46°F (8°C), low 22°F (-6°C) December: normal high 35°F (2°C), low 15°F (-9°C) JFMAMJJASOND

Best months: May

Which city for what

  • Milder winters: Cheyenne (January high 40°F vs January high 35°F)
  • Cooler summers: Cheyenne (July high 84°F vs July high 89°F)
  • Fewer wet days: Casper (91 a year vs 101 a year)
  • Less snow: Cheyenne (62.9 in vs 71.8 in)
  • Longer growing season: Cheyenne (141 frost-free days vs 117 frost-free days)
  • More comfortable days: Cheyenne (89 a year vs 74 a year)

Listed only where the difference is at least 3°F in highs, 10 days a year or 3 in of snow.

Season by season

SeasonAvg high CheyenneAvg high CasperWet days CheyenneWet days Casper
Winter (Dec-Feb)40°F36°F1820
Spring (Mar-May)56°F57°F3129
Summer (Jun-Aug)81°F85°F3221
Fall (Sep-Nov)60°F60°F2121

Side by side over a year

CheyenneCasper
Hot days (90°F+)1538
Freezing nights171183
Muggy days00
Comfortable days8974
Precipitation15.4 in12.2 in
Snowfall62.9 in71.8 in
Frost dateslast May 12, first Oct 1last May 26, first Sep 22
Daylight in June / December15.1 h / 9.3 h15.3 h / 9.1 h
Best monthsMay, JuneMay

Day counts from each city's daily records, 1991-2020. Comfortable days: highs 65-80°F and dew point under 60°F.

Month by month

MonthHigh CheyenneHigh CasperWet days CheyenneWet days Casper
January40°F35°F56
February41°F38°F77
March49°F49°F88
April55°F56°F1110
May64°F67°F1311
June77°F80°F119
July84°F89°F117
August82°F87°F106
September73°F76°F77
October59°F60°F78
November48°F46°F66
December39°F35°F67

Both charts use the same temperature scale.

Where the numbers come from

  • Cheyenne, WY: temperature from Cheyenne (USW00024018), 1.1 mi NE of the city center; precipitation from Cheyenne (USW00024018). NOAA 1991-2020 normals and daily records.
  • Casper, WY: temperature from Casper Natrona Co Airport (USW00024089), 7.9 mi WNW of the city center; precipitation from Casper Natrona Co Airport (USW00024089). NOAA 1991-2020 normals and daily records.

Every station for each city, including humidity and frost, is listed on the city page. Methodology.