Casper receives its highest rainfall in May, while humidity peaks during winter months.
🌧️ Wettest:May — 66 mm☀️ Driest:Jan — 17 mm
💧 Humidity peaks at 72% in Jan · annual avg 55%
🌍 Climate Summary
Avg Annual Temp:47.7°F
Avg Annual Rainfall:387 mm
Avg Humidity:55%
Data Period:1981 – 2025
Casper Climate Overview
Casper has a temperate climate with warm summers and freezing winters.
Temperatures peak in Jul and drop to their lowest in Jan,
while rainfall is highest during spring and early summer months.
Humidity remains moderate throughout the year, especially during winter months, creating cold and dry conditions.
📈 Yearly Trends
The warmest year in Casper's recorded history was 2012
(avg: 52.3°F),
while the coldest year was 1993
(avg: 43.3°F),
based on annual average temperatures.
📊 Key Climate Trends
🌡️ Casper's temperature shows a slight warming trend over the past decade
📈 Minimum temperatures show a slight warming trend in recent years
🌧️ Rainfall varies year-to-year without a clear long-term trend
🌡️ Annual Temperature Trend
View Range:
Average annual high/low · Last 10 years · °F
Casper's temperatures shows a slight warming trend over the past decade.
The highest recorded temperature reached
102.7°F in Jul 2001,
while the lowest dropped to
-26°F in Dec 1983.
🌧️ Annual Precipitation
View Range:
Total annual precipitation · Last 10 years · mm/year
Annual rainfall in Casper shows noticeable variation. Rainfall varies year-to-year without a clear long-term trend.
Based on 45 years of data (1981–2025), Jul is typically the hottest month in Casper, Wyoming, with average high temperatures around 98°F.
What is the coldest month in Casper?▼
Jan is the coldest month in Casper, with average low temperatures around -2.8°F.
What is the rainiest month in Casper?▼
May receives the most rainfall with approximately 66 mm, while Jan is the driest with 17 mm.
What was the highest temperature ever recorded in Casper?▼
The highest recorded temperature was 102.7°F in Jul 2001. This is part of the historical record spanning 1981–2025.
What was the lowest temperature ever recorded in Casper?▼
The lowest recorded temperature was -26°F in Dec 1983.
How many years of data does this page cover?▼
This page covers 45 years of climate data from 1981 to 2025. As new data is added to the database the page automatically reflects the updated coverage.
How much sunlight does Casper get?▼
Casper receives the most sunlight in Jun with an average solar radiation of 7.40 kWh/m²/day. This solar radiation data, sourced from NASA POWER, is useful for solar energy planning, agriculture, and understanding seasonal sunshine availability in Wyoming.
Where does this weather data come from?▼
All climate data is sourced from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite and model data. It provides monthly averages for temperature, precipitation, humidity, wind speed, and solar radiation.
📚 Data Source
All weather data is sourced from NASA POWER (Prediction of Worldwide Energy Resources), a NASA project providing solar and meteorological data for renewable energy, building efficiency, and agricultural research.