Wyoming has a semi-arid, continental type of climate (Köppen climate classification BSk) with warm and moderately wet summers and cold winters. Colorado in the south, Utah in the southwest, Idaho in the west, Montana in the north, and South Dakota and Nebraska in the east, border the state. Wyoming is windy and dry compared to the rest of the United States and has more substantial temperate variations over the seasons, mostly due to its topography - the state is a vast plateau divided by mountain ranges such as the Rocky Mountains, at the base of which lie the Great Plains.
The Continental Divide runs north-south in the land-locked Cowboy state, more specifically along its center - the rain waters that accumulate in the nearby areas sink in the soil in the Great Divide Basin. The Rocky Mountains range covers the western two-third parts, while the High Plains, prairie at high elevation, covers the remaining one-third part; the distribution of many high mountain ranges in the landscape has a significant influence on the climate of Wyoming.
Wyoming summers tend to be warm with the average high temperature from 75°F (23.9°C) to 90°F (32.2°C) in the peak of July in the plains whereas the highlands above 2500 meters experience 70°F (21.1°C) to 75°F (23.9°C). Nights, typical of semi-arid zones, cool down faster and the average temperatures are 50°F (10°C) to 60°F (15.6°C). Winters are cold and extreme in a few periods and the highlands. Average low temperatures during January are in the cold 0°F (-17.8°C) to 18°F (-7.8°C) range across different areas and elevations in the state.
Late spring and early summer is the usual precipitation period - Wyoming is a dry state with an average precipitation of 10" (254mm); lowlands receive sparse rainfall in the range of 8" (203.2mm) to 10" (254mm), while the higher elevations average 15" (381mm) to 20" (508mm). Snowfall in the mountain ranges reaches up to 200" (5080mm), while the plains also accumulate significant amounts during the winter.
Wyoming experiences thunderstorms and tornadoes during late spring and early summer. Chinook winds provide a warming effect in some areas during the winter. Winds blow at high speeds across the vast plains until they encounter the high mountain ranges, which provide natural barriers and create temperature extremities along with a semi-arid climate.
Basin recorded the highest ever temperature of 114°F (45.6°C) on July 12, 1900, in Wyoming, while Riverside recorded the coldest temperature of -66°F (-54.4°C) on February 9, 1933.
The best time to visit Wyoming
The best time to visit Wyoming is from mid-summer to autumn, particularly from June to October. Late spring and early summer witness rain and thunderstorms, while early spring lingers with the effects of the cold winter. Summers tend to be moderate in the highlands, but the lowlands see many days in the 85°F (29.4°C) to 95°range. The fall season sees pleasant temperatures, particularly in September and October, and a change of colors in the foliage of the high country. Summer sees a significant rise in tourist numbers, especially in places like the Yellowstone and Grand Teton national parks, where most of the trails are open until October.
The worst time to visit Wyoming
Winter is the worst time to visit Wyoming as the state experiences cold weather with extreme temperatures. Highlands and mountaintops experience intense cold with vast amounts of snowfall often up to 200" (5080mm). The lowlands accumulate less snow, but many of them register approximately 50" (1270mm) during the winter. Winter days are often below freezing point in many parts of Wyoming, and the night's witness even colder temperatures - the season is slow regarding tourist numbers. However, off-season discounts and winter activities attract some visitors.
Wyoming is prone to wildfires, thunderstorms, and tornadoes in late spring and early summer. Hot and dry conditions usually exist at the peak during the summer, which increases the frequency and intensity of wildfires. The lodgepole and ponderosa forests are particularly susceptible to wildfires in dry conditions. Southeastern plains of Wyoming have more thunderstorm days than other parts of the state. The southeastern corner of the state shows increased precedence of tornadoes, which decreases going further westward - in general, the intensity of these storms is smaller compared to some of the other parts of the country.
Weather in January
January is usually the coldest month of the year in Wyoming, with the average low temperatures even below 0°F (-17.8°C) in the northwest regions - low temperatures go well below the average in many places. Central and southwest Wyoming is in the frigid 1°F (-17.2°C) to 32°F (0°C) average range with short days as the daily sunshine lasts for an average of 4 to 5 hours. The eastern and southern parts of the state are generally warmer than the rest: Buffalo averages between 14°F (-10°C) to 36°F (2.2°C), while Cheyenne, the capital of Wyoming, is in the cold range of 18°F (-7.8°C) to 40°F (4.4°C). Winds are regularly in the 30 to 40mph (64.4km/h) range, while many a time the gusts blow with speeds in the 50 to 60mph (96.6km/h) range - strong winds from the west and southwest directions force trees to lean towards east or southeast in many localities. Chinook winds help to resist the drop in temperatures and corresponding snow accumulation. Beware, January is the snowiest month of the year, particularly in the higher ranges of the mountains where it can easily cross 50" (1270mm).
Weather in February
February is a chilly winter month in Wyoming with the state in the firm grip of the freezing weather. Nights are bitterly cold, while an average of 15 days sees a fair amount of sunshine. Up in the northwest, Cody at an average high temperature of 40°F (4.4°C) and Jackson with 33°F (0.6°C) barely manage to push the mercury above freezing during the day, while most of the central and eastern parts of Wyoming see daily highs of 35°F (1.7°C) to 40°F (4.4°C). Snowfall is 10" (254mm) to 15" (381mm) in many places, with a general decrease in the amount of snow towards the south and east. Blizzards are likely in many places that dump vast amounts of snow, but the sparse population and the small number of cities in Wyoming mean that the effect is not as pronounced as that in the American northeast. Overall, February is an avoidable month to visit Wyoming with better weather in the other periods of the year.
Weather in March
March is a cold month even though it starts the spring season in Wyoming. Day high temperatures average 35°F (1.7°C) to 50°F (10°C) across different regions of the state. The Big Horn Basin, especially its lowest parts as well as the lower elevations of the northeast and eastern parts of the state, are warmer compared to the rest of the state. March seldom registers more than 1" (25.4mm) of rain in most areas, but snowfall touches fair numbers - northwest Wyoming averages 15" (381mm), while the southeast laps up 10" (254mm) to 15" (381mm), with the remaining areas in between 5" (127mm) to 10" (254mm). Average low temperatures are well below freezing such as 14°F (-10°C) in South Pass City, 20°F (-6.7°C) in Devils Tower and 22°F (-5.6°C) in Casper. March seems more like the tail of winter than the arrival of spring, with the sun still not making a regular presence on the horizon. By the end of March, tourists can also experience the start of the growing season in many places in Wyoming. Be sure to pack warm clothes, as the weather is still cold!
Weather in April
April transitions the cold conditions to warm temperatures with the advent of spring in entire Wyoming. Day temperatures are usually in the warm 50°F (10°C) to 60°F (15.6°C), while nights are mild in the 35°F (1.7°C) to 45°F (7.2°C) across the state. April sees a bit of rain with an average of 1" (25.4mm) to 2" (50.8mm) in the state, which gradually progresses in numbers up to summer. Lakes and springs start to meltdown, and the sound and smell of freshwater are refreshing in the backdrop of the mountains. Snowfall tapers down everywhere, barring the high mountain ranges as the sun shines more regularly. There is much enthusiasm as the melting of snow provides a start to the fishing season along with kayaking and canoeing, especially in the canyons. It is not odd for travelers to come across bison, elk, or bighorn sheep in a quest to explore the wildlife as the weather warms up. Pack layers of clothing when exploring the high mountain trails that start to free up by late April.
Weather in May
May is a beautiful warm month with many sunny days in Wyoming with the land blooming with flowers and the singing of the birds. Tourist numbers go northwards as comfortable day temperatures in the 55°F (12.8°C) to 70°F (21.1°C) and comfortable night temperatures above freezing in the 35°F (1.7°C) to 45°F (7.2°C) range, set in across the majority of the state. Rain returns in better numbers with 2" (50.8mm) to 3" (76.2mm) almost everywhere, while snow is negligible, barring in a few places like Yellowstone and the high mountains. The fresh air of spring with a distinct lack of humidity is a great time to visit Wyoming and its beautiful national parks. Spring sees many activities like hunting, trailing, biking, and fishing as the lakes, rivers, and mountains witness the melting of snow. Be sure to carry rain protection as hailstorms occur in fair numbers - it is a good idea to keep track of the local weather while engaging in outdoor adventures.
Weather in June
June brings pleasant summer temperatures in Wyoming that draw tourists from all over the country to its natural beauty and wildlife, among many other attractions. Average high temperatures are between 65°F (18.3°C) to 70°F (21.1°C) in the northwest, while the rest of the state records warmer temperatures of 70°F (21.1°C) to 85°F (29.4°C). Jackson registers an average low temperature of 37°F (2.8°C) in the northwest, while Thermopolis in the central, Buffalo in the northeast and Torrington in the southeast parts of the state, all record a warm 50°F (10°C). Wyoming summers are prone to occasional thunderstorms and tornadoes of small intensity, most of which do not touch the ground and, even if they do, lose much of their strength to cause any sustainable damage. Hailstorms cause more destruction than tornadoes as they damage the crops. Keep in mind that rainfall is sparse but mainly occurs during the summer in Wyoming, while planning a visit to the state.
Weather in July
July is usually the hottest month of the year in Wyoming. The summer weather is temperate and delightful as the average high temperatures across the state are 75°F (23.9°C) to 90°F (32.2°C); a few places touch 95°F (35°C) but a mercury reading of 100°F (37.8°C) is rare. Summer nights are around a comfortable 45°F (7.2°C) to 55°F (12.8°C) - it is one of the best times to visit Wyoming and tourists arrive in droves, especially for camping and fishing in the national parks. Rain is frequent but does not last for a long time and averages around 1" (25.4mm) to 2" (50.8mm) in most places. Wyoming is one of the least humid and dry areas in America, with an average humidity of 50% in July. Brilliant sunshine, coupled with moderate temperatures and clear skies in the peak of summer is hard to beat elsewhere in the continental United States. July is the high tourist season, so do not expect a discount in rates as camping grounds and lodges are scarcely vacant.
Weather in August
August is a wonderful summer month with swelling tourist numbers in Wyoming. The average temperatures are in the 45°F (7.2°C) to 85°F (29.4°C) range with 24 sunny days across the state. The southeast mountain ranges, such as Laramie have moderate temperatures in the 47°F (8.3°C) to 78°F (25.6°C), while the northeast is a little higher in the range of 52°F (11.1°C) to 86°F (30°C). Burgess Junction in north-central Wyoming is a little cooler between 40°F (4.4°C) to 70°F (21.1°C). Rain is sparse to the tune of 1" (25.4mm) to 2" (50.8mm) and is not a threat to outdoor activities. By late summer, most parts of the state experience little rainfall, and the conditions are dry. Light clothing is usually sufficient in August to wade through the river waters or traverses the high mountain trails. Watch out for wildfires in the dry season and keep an eye on thunderstorms, which arrive unexpectedly and throw a spanner in vacation plans.
Weather in September
September is a getaway to the beautiful autumn season of Wyoming with moderate temperatures and a brief splash of colors in the landscape that is usually brown prairie or white snowy. Early fall sees the average warm high temperatures of 60°F (15.6°C) to 80°F (26.7°C) range and the average low temperatures in the mild 32°F (0°C) to 47°F (8.3°C) range. Rain is slight to the tune of 1" (25.4mm) in many places with numerous sunny days as the skies are clear with little moisture in the air. Hordes of tourists flock Yellowstone during this time as the temperatures are in a pleasant 35°F (1.7°C) to 70°F (21.1°C) range, all the trails are open, and it is a great time to experience the wilderness in full bloom. Autumn is a great time to visit Wyoming as the weather is pleasant, and the days have comfortable temperatures, while the nights are ideal to light and sit by campfires - remember that the cold increases with altitude!
Weather in October
October lies in the middle to a late period of the autumn season in Wyoming. Average high temperatures tend to be comfortable in the day in the 55°F (12.8°C) to 65°F (18.3°C) but the nights are cold as the average low temperatures drop below 32°F (0°C) in most areas. October also witnesses the first snow of the season in many places that accumulate up to 5" (127mm). Sunny days with a drizzle of rain are common as the tourist numbers see a gradual decrease. Moran in the northwest register average temperatures of 24°F (-4.4°C) to 54°F (12.2°C), while Rock Springs is between 32°F (0°C) to 57°F (13.9°C). In the central part, the Wind River mountain range sees freezing temperatures and the arrival of snow. Aspens, maples, and willows turn orange, red, and gold during the fall - great places to witness the fall colors is Aspen Alley in the Sierra Madre as well as the national parks. Bike, hike, boat, or horse riding - there are many ways to enjoy the fall colors!
Weather in November
November is a transitional month from the brief autumn in Wyoming that sees a drop in temperatures in the state. Average low temperatures are well below the freezing and range in between 15°F (-9.4°C) to 25°F (-3.9°C). The days are windy with a touch of rain and temperatures are usually from 45°F (7.2°C) to 55°F (12.8°C). Most of the places receive upwards of 10" (254mm) of snow as the ground changes color to white. Sunny days are interspersed with cold days where the sun is present for only a few hours in the sky. Rain is usually 1" (25.4mm) to 2" (50.8mm) in most parts of the state and takes the form of ice and snow. November ends the summer tourism in Wyoming and kicks up enthusiasm for winter adventures in the snow for those who can bear the frigid temperatures. The weather conditions are like winter with cold, ice, and snow in most places, with the sun showing its weak presence for brief periods. It is an excellent idea to pack up and leave Wyoming by the end of November!
Weather in December
December lies in the cold winter with the average high temperatures in the 24°F (-4.4°C) to 41°F (5°C) range and the average low temperatures in the freezing 1°F (-17.2°C) to 17°F (-8.3°C) range across the state. The eastern portion of Wyoming is comparatively milder with high temperatures in the 35°F (1.7°C) to 41°F (5°C) and low temperatures above 10°F (-12.2°C), while the western and northern areas frequently see nights drop well below 10°F (-12.2°C). Rain is negligible in most parts of the state as only a few places like Old Faithful in Yellowstone National Park register a meaningful 3.2" (81.3mm). Snowfall is heavy in the northwest part of the state, such as Moose, which records 44" (1117.6mm), while the rest of the lowlands register 10" (254mm) to 15" (381mm). December usually wears a blanket of snow around the state as a few tourists brave the cold to enjoy activities like snowmobiling, snowshoeing, cross-country skiing, snow tubing, among others - take care to wear layers of warm clothing before engaging in outdoor activities.