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.

- Sunday 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 FRIDAY NIGHT/

Issued at 120 PM MDT Thu Jul 16 2026

Today and tomorrow should look relatively similar as upper level ridging remains centered over the region, with a surface frontal boundary stalled out along or just west of our CWA. Flow positioning will allow monsoonal moisture to lift up and into western Wyoming, but until later into the weekend, it's unlikely to make much of an impact for our area. That being said, upslope flow and some at least meager PWAT values around 0.5-0.75" may fuel some very isolated shower or thunderstorm chances as evidenced by high resolution guidance producing a few echoes for our zones west of the Laramie range, but with weak flow aloft this activity will be fairly stationary, and combined with inverted V sounding profiles, much of this will be virga that struggles to make it to the surface and likely produces dry lightning and breezy winds. Still, can't rule out at least an isolated cell actually bringing rain to the ground, but don't expect much out of this activity today and tomorrow. Otherwise, our cycle of diurnal winds continues, with breezy conditions during the afternoon and relaxing during the evening and night. Relative humidity values remain in the 15-20% range, keeping our fire weather threat elevated but not critical. Temperatures each day range in the upper 80's to upper 90's with a site or two in western Wyoming and/or the Nebraska Panhandle potentially reaching triple digits, hot but not quite warm enough to validate a heat advisory yet (though this may change moving into the weekend).

LONG TERM /SATURDAY THROUGH WEDNESDAY/

Issued at 120 PM MDT Thu Jul 16 2026

Saturday...With the ridge aloft remaining parked over Wyoming, and warm mid level temperatures producing enough CIN, convective inhibition, this will limit areal coverage to isolated to widely scattered showers and thunderstorms over our Snowy and Sierra Madre Ranges in the afternoon, and over much of Carbon County including Rawlins in the evening...otherwise dry.

Sunday...GFS progs the ridge aloft over the northern Rockies to be flattened somewhat with zonal flow developing over Montana and northern Wyoming. A weak perturbation, or shortwave trough aloft, will move across our counties in the afternoon and evening, with monsoonal moisture advecting into our western counties west of I-25, where we anticipate scattered showers and thunderstorms to develop in the afternoon west of I-25, with the greatest areal coverage over the Snowy, Sierra Madre and northern Laramie Ranges. So, more beneficial rain will occur. Monsoonal moisture is progged to advect further eastward in the evening, spawning isolated to scattered showers and thunderstorms for our counties east of I-25, with lesser coverage over the Nebraska Panhandle.

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 and likely, 40 to 80 percent POPS, with the greatest coverage over and near our mountain zones.

Tuesday-Thursday...The zonal flow aloft continues with abundant monsoonal moisture remaining over our CWA, County Warning Area, helping to produce scattered to numerous showers and scattered thunderstorms in the afternoons and evenings with more beneficial rainfall, again with the highest areal coverage over our Snowy, Sierra Madre and Laramie Ranges.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 1135 AM MDT Thu Jul 16 2026

Dominant ridging will continue aloft, leading to a paucity, or minimal amount of clouds, other than some mid and high level clouds west of I-25. No precipitation expected.

High confidence in minimal flight concerns or issues with VFR continuing. The typical gusty winds to 25 knots will occur until sunset due to mix down winds and surface pressure gradients, then winds will subside after sunset, and once again begin the diurnal cycle of wind gusts to 20 knots at Laramie after 15Z Friday. Minimal winds elsewhere after mid morning Friday.

CYS WATCHES/WARNINGS/ADVISORIES

WY...None. NE...None.