CHEYENNE, Wyo. — Southeast Wyoming is currently experiencing strong winds and a drop in temperatures due to a potent upper-level shortwave moving through the region. Winds gusting between 50 and 60 mph in the wind-prone areas will gradually diminish this morning, according to the National Weather Service in Cheyenne.
Much cooler temperatures are expected across the Cheyenne area today and Wednesday. An active weather pattern later this week could bring strong to severe thunderstorms by Thursday.
A cold front passed through the region yesterday evening, bringing strong winds and significantly cooler temperatures. Winds have reached gusts of up to 63 mph at Cheyenne’s airport. These strong winds are expected to ease by midday, with the risk of high winds concluding around 9 a.m. when the current high wind warnings expire.
Unseasonably Cool Air
The system is bringing unseasonably cool air across the area today. Temperatures at the 700-millibar level have dropped below freezing in western and northern counties. This is well below the average for this time of year. High temperatures today are expected to be 10–15 degrees below average.
Drier air is moving into the lower atmosphere behind the cold front. However, a narrow area of moisture remains south and east of a line from Laramie to Wheatland and west of the Wyoming–Nebraska border.
After a brief clearing this morning, mid-level cloud cover is expected to return this afternoon. There might be a few showers near the Laramie Range, but significant precipitation is unlikely.
Changes in Winds and Temperatures
Tonight, a surface high-pressure system will slide down the eastern side of the Rockies, settling into the central and northern Plains. As this system moves east, the pressure gradient will reverse, bringing easterly to southeasterly winds to the High Plains. This will increase moisture in the area and push the dryline as far west as Carbon County by late Wednesday.
The increased moisture may result in clouds and fog along the Interstate 80 corridor, preventing temperatures from dropping too low. However, Wednesday morning will still be chilly with a low in the 40s. Cloud cover is expected to persist throughout the day, holding down high temperatures.
Some areas, especially along the I-80 corridor from Cheyenne to Sidney, could see highs 15–20 degrees below average.
Meanwhile, the upper-level trough will stall and start to lift northward on Wednesday. This will bring southerly flow back into the area, resulting in decent isentropic lift — a type of atmospheric lifting that can cause showers and storms. Severe weather is unlikely, but isolated large hail could occur if instability increases.
Detailed Forecast for Cheyenne
- Today: There is a 20% chance of showers after 3 p.m. The clouds will increase, with a high near 70. It will be windy, with a west-northwest wind at 25–30 mph shifting to the north-northwest at 15–20 mph in the afternoon. Winds could gust as high as 45 mph.
- Tonight: There is a slight chance of showers and thunderstorms before 9 p.m., then a slight chance of showers between 9 p.m. and midnight. The sky will be partly cloudy, with a low around 42. There will be a northeast wind at 5–15 mph. The chance of precipitation is 20%.
- Juneteenth: There is a slight chance of showers between noon and 3 p.m., then a slight chance of showers and thunderstorms after 3. The weather will be partly sunny, with a high near 62. It will be breezy, with a south-southeast wind at 10–15 mph increasing to 15–20 mph in the afternoon. Winds could gust as high as 30 mph. The chance of precipitation is 20%.
- Wednesday Night: There is a 30% chance of showers and thunderstorms. The sky will be mostly cloudy, with a low around 49. It will be breezy, with a southeast wind at 10–20 mph.
- Thursday: Showers are likely, and a thunderstorm is possible, after noon. The weather will be partly sunny, with a high near 83. There will be a south wind at 10–15 mph, with gusts as high as 25 mph. The chance of precipitation is 60%.
- Thursday Night: There is a 30% chance of showers and thunderstorms before midnight. The sky will be mostly cloudy, with a low around 56.
- Friday: There is a 40% chance of showers and thunderstorms after noon. The weather will be mostly cloudy, with a high near 82.
- Friday Night: There is a chance of showers and thunderstorms before midnight. The sky will be mostly cloudy, with a low around 55.
- Saturday: There is a chance of showers and thunderstorms after noon. The weather will be sunny, with a high near 87.
- Saturday Night: The sky will be mostly clear, with a low around 56.
- Sunday: There is a slight chance of showers and thunderstorms. The weather will be sunny and hot, with a high near 92.
- Sunday Night: The sky will be mostly clear, with a low around 59.
- Monday: There is a slight chance of showers and thunderstorms. The weather will be mostly sunny and hot, with a high near 92.
