Casper Climate by Month
Casper, Wyoming, United States
Hot summers and cold winters, with little rain.
Casper has hot summers and cold winters, with little rain. Expect highs of 89°F (32°C) in July and 37°F (3°C) in January, with the coldest nights (January) near 15°F (-10°C). It gets only 11 in (274 mm) of rain a year.
- Warmest month
- 89°F(32°C)
- Average high, July
- Coldest nights
- 15°F(-10°C)
- Average low, January
- Rain per year
- 11 in(274 mm)
- No clear rainy season
- Humidity
- 51%
- Sunniest: July
Best and worst months in Casper
Best for weatherSeptember is the best time for weather in Casper: highs near 77°F (25°C) and about 0.8 in (20 mm) of rain a month.
Least pleasantDecember and January are the least pleasant; January is the coldest, with highs of only 37°F (3°C).
Comfort combines how close the afternoon high is to 75°F (24°C) with how much rain falls and how humid it is. See where the weather is best in September.
Temperature and rain through the year
Highs and lows (°F)
Average highAverage low
Rain (in per month)
Casper weather by month
| Month | High | Low | Rain | Humidity | Sun |
|---|---|---|---|---|---|
| JanJanuary | 37°F(3°C) | 15°F(-10°C) | 0.4 in(11 mm) | 64% | 2.0 |
| FebFebruary | 38°F(3°C) | 15°F(-9°C) | 0.6 in(15 mm) | 61% | 2.9 |
| MarMarch | 48°F(9°C) | 24°F(-5°C) | 0.8 in(20 mm) | 56% | 4.3 |
| AprApril | 56°F(14°C) | 30°F(-1°C) | 1.3 in(32 mm) | 52% | 5.0 |
| MayMay | 67°F(19°C) | 39°F(4°C) | 2.2 in(56 mm) | 51% | 6.1 |
| JunJune | 79°F(26°C) | 48°F(9°C) | 1.4 in(35 mm) | 45% | 6.9 |
| JulJuly | 89°F(32°C) | 55°F(13°C) | 0.9 in(22 mm) | 37% | 7.2 |
| AugAugust | 87°F(31°C) | 54°F(12°C) | 0.5 in(12 mm) | 39% | 6.1 |
| SepSeptemberBest | 77°F(25°C) | 45°F(7°C) | 0.8 in(20 mm) | 44% | 4.8 |
| OctOctober | 61°F(16°C) | 34°F(1°C) | 0.9 in(24 mm) | 53% | 3.2 |
| NovNovember | 47°F(9°C) | 25°F(-4°C) | 0.6 in(14 mm) | 55% | 2.1 |
| DecDecember | 37°F(3°C) | 17°F(-8°C) | 0.5 in(13 mm) | 60% | 1.7 |
1991–2020 averages. Sun is solar radiation in kWh/m² per day. Highlighted: the most comfortable months.
Places with a similar climate
All 20 places like Casper →- 🇺🇸BillingsMontana, United States · Pop. 117k96%matchSame summer highsSame winter lowsCasper vs Billings →
- 🇺🇸GilletteWyoming, United States · Pop. 33k96%matchSame winter lowsSame humidityCasper vs Gillette →
- 🇺🇸Great FallsMontana, United States · Pop. 60k94%matchSame winter lowsSame humidityCasper vs Great Falls →
- 🇺🇸CheyenneWyoming, United States · Pop. 65k92%matchSame sunshineSame humidityCasper vs Cheyenne →
- 🇺🇸BozemanMontana, United States · Pop. 43k92%matchSame winter lowsSame humidityCasper vs Bozeman →