textproduct: Cheyenne

KEY MESSAGES

- Hot, dry, and breezy conditions continue through Sunday before a much awaited cold front arrives for the start of the week.

- Monday looks to be the last 100+ day for the upcoming week or so, with reduced fire concerns also arriving with cooler weather.

- Monsoonal moisture will attempt to return as early as Monday, leading to increased precipitation chances through much of next week.

SHORT TERM /THROUGH MONDAY/

Issued at 253 AM MDT Sat Jul 18 2026

With the upper-level ridge still firmly in place over Wyoming, hot and dry conditions are expected to continue into the day Saturday. Mostly sunny skies across a majority of the CWA will help temperatures climb about 5 degrees above normal for this time of year. Most locations will see high temperatures in the 90s, but would not be surprised to see a few lower elevation spots reach the low 100s. Some moisture will be present in western Wyoming as the monsoon strengthens over the Desert Southwest and pushes northward. The western portion of the CWA will be on the eastern edge of the monsoon push, so it is possible that a few showers or thunderstorms could develop west of the Laramie Range during the afternoon hours. Hi-Res guidance shows storms initially forming over the high terrain of the Snowy and Sierra Madre Ranges before pushing north throughout the evening. Storms will dissipate by about midnight, with the rest of the night expected to be quiet.

Sunday will be virtually the same as Saturday with hot temperatures continuing and another chance of showers and storms. Highs east of the Laramie Range on Sunday will be about 5 degrees warmer compared to Saturday, prompting a Heat Advisory for most of the aforementioned area. There will be a little less moisture around on Sunday, however, Hi-Res guidance still shows the potential for a few storms developing off the high terrain and moving into the plains through the afternoon hours. Given that less moisture is present, showers and storms will likely end around sunset.

LONG TERM /MONDAY NIGHT THROUGH FRIDAY/

Issued at 220 PM MDT Fri Jul 17 2026

Monday...Monsoonal moisture at low and mid levels increases further, aiding in another increase in late day shower and thunderstorm coverage, and beneficial rains, with coverage increasing to scattered 30 to 60 percent POPS, probability of measurable precipitation, with the greatest coverage over and near our mountain zones.

Tuesday-Friday...A relatively significant pattern change will occur, with "beware" northwest flow aloft developing along with a decent increase in low and mid level moisture and upslope southeast mechanical lift at low levels, and occasional passing shortwave troughs aloft, helping to produce scattered to numerous showers, and scattered thunderstorms in the afternoons and evenings, with beneficial rainfall and possibly some locally heavy rains from some of the slower moving thunderstorms. The most likely locations for locally heavy rain and the greatest areal coverage may be along and east of Interstate 25. On Friday, the GFS progs the last of the passing shortwave troughs aloft to move into Nebraska by evening, with shortwave ridging aloft bulging across Wyoming, thus expect an attendant decrease in areal afternoon and evening shower and thunderstorm coverage.

AVIATION /06Z TAFS THROUGH 06Z SUNDAY/

Issued at 1118 PM MDT Fri Jul 17 2026

VFR conditions at all terminals tonight. A stationary front in the northern Nebraska Panhandle is drifting south. Little to no cloud cover is associated with this feature, however a wind shift at KCDR from the northeast is anticipated shortly. Elsewhere winds are generally light and variable. During the day diurnal heating will increase winds and gusts at all terminals. KRWL has a slight chance of showers and thunderstorms in the evening. The main risks are lightning and brief reduction in visibility. Some shower activity may occur near KAIA from the previously mentioned stationary front in the evening. Cloud debris from nearby convection will increase cloud coverage, but no ceiling concerns are anticipated.

CYS WATCHES/WARNINGS/ADVISORIES

WY...Heat Advisory from noon Sunday to 6 PM MDT Monday for WYZ101- 102-108. NE...Heat Advisory from noon today to 6 PM MDT Monday for NEZ002- 095. Heat Advisory from noon Sunday to 6 PM MDT Monday for NEZ003- 019>021-096.