Climate and monthly weather forecastCasper, WY
Climate and monthly weather forecast
The climate of Casper
Casper, Wyoming, USA, falls under the Köppen climate classification as BSk, signifying a mid-latitude steppe climate. This geographic setting relays a semi-arid environment that sees a strong seasonal temperature variance. Humidity levels follow rather consistent patterns despite the marked temperature variations, spanning from a low of 37% in August to a high of 79% in January.Significant anomalies in rainfall are absent throughout the year, with precipitation appearing the heaviest in May at 1.77" (45mm). However, the region still maintains its arid state as the volume of rain barely touches the half inch mark during its driest months, August and September. Snowfall, on the other hand, displays considerable fluctuation starting December with a peak in February at 5.47" (139mm) and then returning to minimum levels by May.
Solar exposure and daylight maximize during the summer months with June boasting up to 15.3 daylight hours and 11.8 sunshine hours, subsequently dipping during the dark, harsh winters. High wind speeds averaging 12.1mph (19.5km/h) in January top the wind pattern charts, while the peak gust speeds reach 21.9mph (35.2km/h). The cloud cover exhibits a minimal fluctuation pattern, primarily remaining in the 20 to 30% range throughout the year.
The best time to visit Casper
Preference-based periods aside, the most comfortable period to visit Casper would be between May and September, owing to the ideal balance between the temperature range of 61.3°F (16.3°C) to 81.3°F (27.4°C) and daylight hours stretching close to 12 to 15 hours. The summer rain offers a respite from the dry mid-latitude steppe climate, with rates dropping to 0.43" (11mm) by August. This period also witnesses the most extended solar exposure with the UV index spiking in June.The worst time to visit Casper
Undoubtedly, the harsh winter months ranging from December to February classify as the least favorable time to visit Casper. A peak snowfall of 5.47" (139mm) in February coupled with temperatures plunging from 28.9°F (-1.7°C) to 15.1°F (-9.4°C) makes the winter months particularly challenging. Coupled with minimal daylight hours, the cold can be quite stinging. High wind speeds topping 12.1mph (19.5km/h) add to the biting chill, making it uninviting for visitors.Spring weather in Casper
Springtime in Casper, from March to May, translates to a brisk rise in temperatures from a low of 26.4°F (-3.1°C) to 61.3°F (16.3°C). This season witnesses the initial melting of snow, and rainfall becomes prevalent, reaching its annual peak at 1.77" (45mm) in May. The city gradually wakes from its winter slumber, with longer daylight, extended sunshine hours, and noticeably less cloud cover by the end of the season.Summer weather in Casper
Summers offer the most comfortable weather with temperatures climbing to a pleasant 83.5°F (28.6°C) in July. Along with increased temperatures, humidity finds a considerable dip from 55% in May to 37% in August, resulting in more comfort throughout the day. Rainfall registers a consistent dip through the season, stabilizing at 0.43" (11mm) by August. Extended sunshine hours and increased solar UV index compliment the season, with wind activities slowing down their pace.Autumn weather in Casper
Autumn sees temperatures gradually dropping to a low of 36.5°F (2.5°C) by November from the highs of 72.7°F (22.6°C) in September. Rainfall indicates a hike in October at 0.98" (25mm), while snowfall starts to make its presence felt by November. The sunshine hours and daylight duration see a noticeable reduction, and temperature drops start to creep in by the end of this season, hinting at the forthcoming winter.Winter weather in Casper
Winters are cold and harsh in Casper, with temperatures plummeting between 41.5°F (5.3°C) and 15.1°F (-9.4°C). The snowfall, peaking at 5.47" (139mm) in February, results in widespread cover across the city. The sunshine hours go down dramatically, and daytime shortens with cloud cover at prevalent highs of around 32%. The wind chill factor due to the regular and gust wind speeds amplifies the cold, making winter a particularly challenging season in Casper.Weather in January
The weather in Casper, Wyoming during January represents the deep winter chill. With average high temperatures just shy of 29°F (-1.7°C) and lows as cold as 15.6°F (-9.1°C), January holds the coldest temperatures. Moreover, this month experiences considerable snowfall with snow present for over 10 days. Weather in January »Weather in February
Casper, Wyoming in February continues to be gripped by the winter's intensity. Subtle increase in temperatures and reduced snowfall sets the gradual farewell to the winter season. Notably, it experiences a slight increase in the number of rainfall days from 3.6 to 5.3. Weather in February »Weather in March
The spring onset is marked prominently in the month of March in Casper, Wyoming. There is a substantial rise in temperature, providing respite from the intense winter cold. The city starts its journey into warmer weather, with more rain instead of snow, and an increase in sunlight hours from 10.6 to 12. Weather in March »Weather in April
Casper, Wyoming experiences a brisk spring throughout April, characterised by a further climb in temperatures. Changing weather brings the touch of spring along with it, as snowfall effectively ends during this month with rainfall surpassing 1.22" (31mm). Weather in April »Weather in May
May signifies the precursor to summer months in Casper, Wyoming. Transitioning into the hotter season, May receives the highest amount of rainfall over the year, 1.77" (45mm). Under splendid sunshine extending up to 14.7 hours, this month witnesses an amazing bloom of flora. Weather in May »Weather in June
June stands at the prelude of the hot months to come in Casper, Wyoming. Indicative of the forthcoming summer, the month records the precipitous drop in relative humidity from 55% to 44%. Accompanying this is a warm cozy atmosphere with high temperatures ascending above 75°F (23.9°C). Weather in June »Weather in July
July in Casper, Wyoming, truly personifies the summer season with a peak recorded temperature of 83.5°F (28.6°C). Record summer heat, long daylight hours and wealthy sunshine of 11.9 hours paints a typical summer picture. Despite less frequent rainfall, the city retains its green glow under the bright sun. Weather in July »Weather in August
As August arrives, Casper, Wyoming starts witnessing a modest respite from its summer peak. Notably, August records a slight dip in average high temperatures from 83.5°F (28.6°C) to 81.3°F (27.4°C), hinting towards the approaching end of the hot season. Weather in August »Weather in September
September is a transitional month for the weather in Casper, Wyoming. As the city bids farewell to the warm summer temperatures, a significant drop can be seen, sliding to a more comfortable 72.7°F (22.6°C). Preparing for the slide into autumn, it remains pleasant with warm days, less humidity, and cool nights. Weather in September »Weather in October
October ushers in the distinct autumn season in Casper, Wyoming. The clear divide from the hot summer to cooler temperatures becomes more evident, with average highs descending to 54.3°F (12.4°C). The light snowfall, seen in Casper during this month signifies the near approach of winter. Weather in October »Weather in November
November witnesses the advent of the cold season in Casper, Wyoming. The temperatures continue their downward slide, leading the city to gradually embrace the winter chill. Transitioning towards more precipitation, November witnesses an increase in snowfall to 5.47" (139mm). Weather in November »Weather in December
December marks the mid of the cold winter season in Casper, Wyoming, immersing the town in a festive spirit. Suffering the brunt of cold, temperatures plunge dramatically, with average highs dropping to 28.4°F (-2°C) and lows to around 15.1°F (-9.4°C). Weather in December »Updated: Feb 14, 2024
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
With an average relative humidity of 79%, January is the most humid month.
January, August and September are months with the least rain in Casper, Wyoming, when the rain falls for 3.6 days and typically aggregates up to 0.43" (11mm) of rain.
In Casper, Wyoming, during the entire year, the rain falls for 91.6 days and collects up to 9.69" (246mm) of precipitation.
January through May, September through December are months with snowfall in Casper, Wyoming.
Throughout the year, in Casper, Wyoming, there are 61.5 snowfall days, and 32.13" (816mm) of snow is accumulated.
The months with the lowest UV index are January through April, October through December, with an average maximum UV index of 2.
The month with the least sunshine in Casper is February, with an average of 6.1h of sunshine.
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts, and the time zone changes from MST to MDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from MDT to MST.
May is the month with the most rainfall. Rain falls for 14.1 days and accumulates 1.77" (45mm) of precipitation.
In Casper, snow does not fall in June through August.
With an average of 15h and 18min of daylight, June has the longest days of the year in Casper, Wyoming.
The months with the highest UV index in Casper are June through August, with an average maximum UV index of 6.
With its average high temperature of 83.5°F (28.6°C) and a low of 59.5°F (15.3°C), July is regarded as the warmest month in Casper, Wyoming.
The months with the most sunshine in Casper are July and August, with an average of 11.9h of sunshine.
August is the least humid month, with an average relative humidity of 37%.
November is the month with the most snowfall in Casper. Snow falls for 7.1 days and accumulates 5.47" (139mm) of snow.
Casper witnesses the coldest weather in December, with temperatures averaging a high of 28.4°F (-2°C) and a low of 15.1°F (-9.4°C).
With an average of 9h and 6min of daylight, December has the shortest days of the year in Casper.
Average temperature
Casper, WY
The warmest month (with the highest average high temperature) is July (83.5°F).
The month with the lowest average high temperature is December (28.4°F).
The month with the highest average low temperature is July (59.5°F).
The coldest month (with the lowest average low temperature) is December (15.1°F).
Average pressure
Casper, WY
- Average pressure in January:
30.16"Hg - Average pressure in February:
30.11"Hg - Average pressure in March:
29.98"Hg - Average pressure in April:
29.9"Hg - Average pressure in May:
29.89"Hg - Average pressure in June:
29.85"Hg
- Average pressure in July:
29.92"Hg - Average pressure in August:
29.92"Hg - Average pressure in September:
29.94"Hg - Average pressure in October:
30"Hg - Average pressure in November:
30.07"Hg - Average pressure in December:
30.15"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.85"Hg).
Average wind speed
Casper, WY
- Average wind speed in January:
12.1mph - Average wind speed in February:
11.3mph - Average wind speed in March:
11.1mph - Average wind speed in April:
10.9mph - Average wind speed in May:
9.8mph - Average wind speed in June:
9.6mph
- Average wind speed in July:
8.5mph - Average wind speed in August:
8.5mph - Average wind speed in September:
9.4mph - Average wind speed in October:
10.7mph - Average wind speed in November:
11.3mph - Average wind speed in December:
11.7mph
The windiest month (with the highest average wind speed) is January (12.1mph).
The calmest months (with the lowest average wind speed) are July and August (8.5mph).
Average humidity
Casper, WY
The month with the highest relative humidity is January (79%).
The month with the lowest relative humidity is August (37%).
Average rainfall
Casper, WY
- Average rainfall in January:
0.43" - Average rainfall in February:
0.63" - Average rainfall in March:
0.94" - Average rainfall in April:
1.22" - Average rainfall in May:
1.77" - Average rainfall in June:
0.91"
- Average rainfall in July:
0.63" - Average rainfall in August:
0.43" - Average rainfall in September:
0.43" - Average rainfall in October:
0.98" - Average rainfall in November:
0.79" - Average rainfall in December:
0.51"
The wettest month (with the highest rainfall) is May (1.77").
The driest months (with the least rainfall) are January, August and September (0.43").
Average rainfall days
Casper, WY
- Average rainfall days in January:
3.6 days - Average rainfall days in February:
5.3 days - Average rainfall days in March:
7.3 days - Average rainfall days in April:
11.7 days - Average rainfall days in May:
14.1 days - Average rainfall days in June:
9.8 days
- Average rainfall days in July:
8.4 days - Average rainfall days in August:
7.5 days - Average rainfall days in September:
7.6 days - Average rainfall days in October:
7.2 days - Average rainfall days in November:
5 days - Average rainfall days in December:
4.1 days
The month with the highest number of rainy days is May (14.1 days).
The month with the least rainy days is January (3.6 days).
Average snowfall
Casper, WY
- Average snowfall in January:
3.54" - Average snowfall in February:
3.98" - Average snowfall in March:
4.88" - Average snowfall in April:
4.02" - Average snowfall in May:
2.83" - Average snowfall in June:
0"
The month with the highest snowfall is November (5.47").
The months with the least snowfall are June, July and August (0").
Average snowfall days
Casper, WY
- Average snowfall days in January:
10.1 days - Average snowfall days in February:
11.2 days - Average snowfall days in March:
8.3 days - Average snowfall days in April:
7.3 days - Average snowfall days in May:
2.1 days - Average snowfall days in June:
0 days
- Average snowfall days in July:
0 days - Average snowfall days in August:
0 days - Average snowfall days in September:
0.2 days - Average snowfall days in October:
5.3 days - Average snowfall days in November:
7.1 days - Average snowfall days in December:
9.9 days
The month with the highest number of snowfall days is February (11.2 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight / Average sunshine
Casper, WY
- Average daylight in January:
9h and 30min - Average daylight in February:
10h and 36min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 24min - Average daylight in May:
14h and 42min - Average daylight in June:
15h and 18min
- Average daylight in July:
15h and 0min - Average daylight in August:
13h and 54min - Average daylight in September:
12h and 30min - Average daylight in October:
11h and 0min - Average daylight in November:
9h and 42min - Average daylight in December:
9h and 6min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in January:
6h and 36min - Average sunshine in February:
6h and 6min - Average sunshine in March:
8h and 42min - Average sunshine in April:
10h and 0min - Average sunshine in May:
10h and 48min - Average sunshine in June:
11h and 48min
- Average sunshine in July:
11h and 54min - Average sunshine in August:
11h and 54min - Average sunshine in September:
11h and 6min - Average sunshine in October:
7h and 0min - Average sunshine in November:
6h and 48min - Average sunshine in December:
6h and 24min
The months with the most sunshine are July and August (Average sunshine: 11h and 54min).
The month with the least sunshine is February (Average sunshine: 6h and 6min).
Average sunshine days
Casper, WY
- Average sunshine days in January:
20.3 days - Average sunshine days in February:
15.2 days - Average sunshine days in March:
17.3 days - Average sunshine days in April:
12.1 days - Average sunshine days in May:
11.9 days - Average sunshine days in June:
15.3 days
- Average sunshine days in July:
17.9 days - Average sunshine days in August:
17.4 days - Average sunshine days in September:
19.2 days - Average sunshine days in October:
18.5 days - Average sunshine days in November:
20.4 days - Average sunshine days in December:
20.5 days
The month with the most sunshine days is December (20.5 days).
The month with the least sunshine days is May (11.9 days).
Average UV index
Casper, WY
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, March, April, October, November and December (UV index 2).
Average cloud cover
Casper, WY
The month with the most cloud cover is February (Cloud cover 36).
The month with the least cloud cover is August (Cloud cover 13).
Average visibility
Casper, WY
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
