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 SUNDAY NIGHT/

Issued at 127 AM MDT Fri Jul 17 2026

Upper-level ridging continues to dominant much of the CONUS today through much of next week. This upper-level high will result in largely light and variable winds throughout the atmosphere as the ridge slowly strengthens through the weekend. A 594dm high at 500mb develops overhead for late Saturday through the day Sunday, leading to a very hot weekend in store for much of the region. Afternoon highs on Friday will be in the mid-80s to near-100F, while afternoon highs on Saturday will be warmer in the upper-80s to 100F+ across western Nebraska. Sunday does appear to be the hottest day, with afternoon highs in the upper-80s to 105F in western Nebraska as the upper-level high strengthens overhead. With dry conditions expected for most areas today through Sunday, afternoon relative humidity values will drop into the 15 to 25 percent range everywhere Friday through Sunday afternoon. Luckily, winds will be just below critical thresholds, so elevated, but not critical, fire conditions are anticipated to continue Friday onwards. No fire weather headlines have been issued at this time. Consideration was given to the potential need for a Heat Advisory across northern portions of the region on Sunday, but will defer to future shifts to determine the necessity as models continue to come into better agreement on forecast highs for Sunday.

Monsoonal moisture will start to try to return to the region as early as Saturday afternoon, mainly west of the Laramie Range. As a result, precipitation chances start increasing Saturday onwards, but an isolated shower or storm over the mountains cannot be ruled out this afternoon (~15% chance). More "widespread" precipitation chances start to return Saturday afternoon, mainly west of the Laramie Range, with around a 25 to 35% chance for precipitation in Carbon County. Sunday will see the best chance for precipitation in the short term forecast, with PoPs in the 35 to 50 percent range mainly along and west of I-25. Significant precipitation does not look likely as the best monsoonal moisture will not arrive until next week, but up to a quarter inch of precipitation will be possible Sunday afternoon where the majority of showers/storms develop over northern Albany County. Precipitation chances continue to improve into the upcoming work week.

LONG TERM /MONDAY THROUGH THURSDAY/

Issued at 127 AM MDT Fri Jul 17 2026

Upper-level ridging is progged to continue through much of the upcoming week, with little indication of the ridge moving out of the area anytime soon. Long range models suggest that the ridge will retrograde slightly and strengthen over the Intermountain West once again Tuesday into Wednesday, leading to more westerly to northwesterly flow aloft. 500mb flow suggests that the monsoon will start to take hold as early as Monday evening into Tuesday, leading to increasing moisture across the CWA. With northwesterly flow aloft developing by Wednesday, a favorable setup is expected for daily thunderstorms chances to return with some severe storms potentially possible. Severe threat is very uncertain at this time, due to the best pattern not evolving until Wednesday and after. Luckily, after another hot day on Monday under the strengthening upper-level high, a stout cold front will push through Monday evening into Tuesday, dropping temperatures from highs of the mid-80s to low-100s on Monday to highs in the low-80s to low-90s Tuesday onwards. With cooler temperatures and increasing moisture influx due to monsoonal flow, fire concerns will drop off rapidly Tuesday onwards. Afternoon minimum humidity values will remain at or above about 30% most day this upcoming week, which is well above critical thresholds. Winds will remain breezy, though below Red Flag criteria. Unfortunately, these winds will not be enough to make temperatures feel cooler than actual temperatures, due to increasing humidity across the region.

AVIATION /12Z TAFS THROUGH 12Z SATURDAY/

Issued at 500 AM MDT Fri Jul 17 2026

VFR conditions expected this morning through the 12Z TAF period. Some high-level clouds move into all the terminals by mid-day, but clear skies return after sunset. Breezy conditions develop around mid-day, with all terminals gusting 20 to 25kts this afternoon and evening. Calmer winds return for the late evening into the overnight hours.

CYS WATCHES/WARNINGS/ADVISORIES

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