textproduct: Cheyenne

KEY MESSAGES

- Red Flag Warning continues for parts of southeast Wyoming west of I-25 until 8 PM this evening.

- Another Red Flag Warning is in effect from 11 AM to 8 PM Saturday for all of southeast Wyoming for very low humidities and significant gusty winds.

- Hot temperatures will continue through Monday before the heat is lessened for Tuesday onward with isolated to scattered showers and thunderstorms expected for Tuesday through next Friday.

SHORT TERM /THROUGH SATURDAY NIGHT/

Issued at 250 PM MDT Fri Aug 7 2026

Tonight... Thank you very much to our neighboring NWS office team at Riverton, Wyoming for providing service backup today to our NWS Cheyenne team. Inherited Red Flag Warning is in decent shape looking at bone dry relative humidities and expected winds currently through this evening. Thus will continue the Red Flag Warning for our fire weather zones across much of Carbon and portions of Albany Counties until 8 PM. Another quiet and comfortable overnight with excellent radiational cooling due to low dewpoints. Boundary layer winds and humidities suggest scattered to widespread low clouds developing across the Nebraska Panhandle after midnight and until early morning after daybreak, with a decent low level jet also bumping up the winds, especially at typically windy Chadron and Alliance under low level jet conditions.

Saturday...Main challenge will be Fire Weather concerns. Northwest flow aloft continues and with a decent bump in the mid level winds around 700 mb, near 10,000 feet MSL, looking at decent mix down winds exceeding Red Flag Warning criteria for all of southeast Wyoming looking at NAM MET and MAV data, especially with a decent 700 mb jet moving overhead in the afternoon. Minimum humidities will definitely be low enough for criteria, and thus we will issue another Red Flag Warning for all of our southeast Wyoming fire weather zones. Winds across the Nebraska Panhandle will be lighter and thus we will hold off on a Red Flag Warning there. Soaring temperatures once again based on projected 700 mb temperatures, full sun and downslope warming projecting maximum temperatures from 90 to 102 degrees. Fortunately, apparent temperatures and heat index values will be reasonable due to low relative humidities.

Saturday night... Minimum temperatures will be moderated again by the above normal airmass, though still quite comfortable for sleeping with the windows open due to excellent radiational cooling. Continued dry with scarcity of available moisture.

LONG TERM /SUNDAY THROUGH FRIDAY/

Issued at 250 PM MDT Fri Aug 7 2026

A suppressed ridge pattern will continue throughout the majority of the long-term forecast period. Monsoonal ridging throughout the weekend will gradually subside, with the 500mb jet generally positioned from the Washington/Oregon cascades and stretching across the northern Rockies into the high plains of Montana and northern Wyoming. South of this feature, gradually deepening moisture will spread across the central and southern Rockies from the Four Corners eastward through the high plains. PWAT values at selected sites across southeast Wyoming and western Nebraska all show a steady rise each day from Sunday through the end of the week. This will lead to increasing coverage of showers and thunderstorms each day. By the Wednesday-Friday timeframe PWAT normalized anomalies in ensemble guidance will run around 2 to 2.5 standard deviations above the mean. This will result in high confidence of afternoon thunderstorms, some of which may contain heavy drenching downpours. Despite better thunderstorm chances, severe weather remains generally unlikely in southeast Wyoming with mostly light westerly flow in the mid and upper-levels present. Farther east into the Nebraska Panhandle, some faster flow aloft will begin to impinge on the area from the north by Wednesday as the aforementioned ridge of high pressure continues to become more suppressed to the south. Low-end wind shear values on the order of 30-40 knots may assist with multicell storm modes that could produce organized outflow wind events during the afternoon hours from Wednesday through Friday. High confidence exists in above-normal temperatures continuing through the entire long-term period. However, increasing coverage of afternoon thunderstorms from mid-week onward will likely limit temperatures somewhat, generally running around 10 degrees above normal instead of the near- record daily heat we will experience this weekend. Overall, generally high confidence exists in the long-term period with excellent agreement in ensemble guidance with regard to synoptic forecast features.

AVIATION /00Z TAFS THROUGH 00Z SUNDAY/

Issued at 532 PM MDT Fri Aug 7 2026

Most terminals will stay in VFR conditions through the forecast period, however KSNY and KAIA may experience reduced CIGs around 12 to 15z. At KLAR smoke is reducing visibilities to below 10SM. A low level jet will develop tonight around the Nebraska Panhandle terminals. A shallow inversion near the surface may keep sustained surface winds on the lower side, between 8 and 15 knots, with gusts occasionally mixing to the surface up to 25 knots. A byproduct of this inversion are some low level wind shear concerns for primarily KCDR and KAIA through 12z. Surface moisture increases to near saturation at KAIA and KSNY which may create a deck of low CIGs to around 1kft around sunrise. Fog seems unlikely, but not impossible. Winds decrease by morning leaving most terminals variable through the early afternoon when a wind shift out of the west to northwest occurs from a retreating frontal boundary. Some isolated showers and storms are possible late afternoon, but probabilities are too low to include in TAFs at this time.

CYS WATCHES/WARNINGS/ADVISORIES

WY...Air Quality Alert until noon MDT Monday for WYZ101>119. Red Flag Warning from 11 AM Saturday to 9 PM MDT Sunday for WYZ417>433. Red Flag Warning until 8 PM MDT this evening for WYZ420>422- 425>427. NE...None.