Extreme Wyoming Weather Swings From 10 Inches Of Snow To 90 Degrees In A Week

Last week, parts of Wyoming got up to 10 inches of snow during blizzard conditions. By Monday, temperatures were in the 80s and flirting with record highs—on their way into the 90s by Wednesday. While Wyomingites may wonder why the state’s climate suddenly has the temperament of a moody teenager, meteorologists say the state has always been subjected to “roller coaster” weather in May.

Cowboy State Daily meteorologist Don Day said these week-to-week changes are part of what he affectionately calls “Moody May.” “May is very susceptible to mood swings,” Day said. “In less than a week, we’ve had a snowstorm, funnel clouds, severe thunderstorm warnings, and record-breaking high temperatures.”

Less than a week ago, Cheyenne received an inch of liquid water from rain and snow, with temperatures statewide dropping into the 30s and 40s. On Monday, Cheyenne’s daytime high was 82 degrees. Meteorologist Adam Dziewaltowski with the National Weather Service office in Riverton said Lander’s record high for May 11 was 84 degrees, set in 1940; Monday’s forecast was 85 degrees. Casper’s record of 83 degrees, also set in 1940, was expected to be broken with a high of 84.