textproduct: Cheyenne

KEY MESSAGES

- A Red Flag Warning is in effect for all areas along and east of Interstate 25 from noon Tuesday through 10 PM Wednesday.

- The High Wind Watch for the typical wind prone regions of southeast Wyoming has been upgraded to a High Wind Warning from 6 PM Tuesday through 3 PM Wednesday.

- Fire weather concerns continue through the end of the work week with dry conditions and minimal chances of precipitation.

SHORT TERM /THROUGH WEDNESDAY NIGHT/

Issued at 108 PM MDT Tue Jun 16 2026

A hot and breezy day continues across the area this afternoon. Current observations show temperatures in the 80s and 90s across a majority of the forecast area with gusts of 25 to 45 MPH. Winds will ease briefly this evening east of the Laramie Range, but will pick up west of the Laramie Range. An incoming cold front will cause MSLP gradients to tighten, as well as 850 and 700 mb CAG to CPR height gradients. This steepening of gradients will cause winds aloft to increase to about 60 kts over the typical southeast Wyoming wind prone areas. Strong subsidence will likely help facilitate getting these winds down to the surface. High Wind Warnings are in effect for the wind prones starting this evening and continuing through part of the day Wednesday. The strongest winds are expected early Wednesday morning with gusts of 60 to 70 MPH possible. In-house guidance is also fairly confident in high winds occurring, suggesting a 50 to 60 percent chance. Winds will begin to gradually pick up east of the Laramie Range sometime after midnight with the passage of a cold front. Ahead of this cold front, Hi-Res guidance shows the potential for some scattered showers and storms around midnight. Model soundings from the GFS show very weak instability around this time, but it could be enough to produce a few lightning strikes if showers can make it into the extreme northern Nebraska panhandle. Given fairly poor overnight humidity recoveries in that area, opted to add slight chance PoPs as well as dry lightning since the Red Flag Warning in effect continues through Wednesday evening.

As expected, temperatures on Wednesday will be cooler behind the front, with the northern zones of the CWA seeing the biggest change in high temperatures. Areas north of the North Platte River Valley will see high temperatures about 10 to 15 degrees cooler than Tuesday. Most other areas will see about a 5 to 10 degree reduction in high temperatures Wednesday. For the most part, this will put a majority of cities at near average high temperatures. Critical fire weather conditons continue for one more day, mainly due to the strong/high winds. Downsloping winds will contribute to keeping the surface dry with relative humidity at 20 percent and lower. Winds outside of the wind prones, especially in the northern zones and the Nebraska panhandle will also be exceptionally strong. A low-level jet will park itself over the northeast corner of the CWA on Wednesday, leading to wind gusts of 40 to 50 MPH. Winds will eventually ease across the CWA around sunset, leading to a quiet overnight.

LONG TERM /THURSDAY THROUGH TUESDAY/

Issued at 108 PM MDT Tue Jun 16 2026

We start Thursday off a little chillier than the last few days due to the cold front passage on Wednesday. Lows in the 40s to low 50s are expected area wide in the morning before rising to the 70s with a few 80s in valley areas. Overhead we have an impressively long jet streak extending from coast to coast on the southern ambit of a trough in Canada. This will give way to a ridging pattern Friday. Much like Thursday, Friday is expected to be mild and sunny with afternoon temperatures 10 degrees warmer at most spots. Given the low humidity values in the early part of the long term we do have lingering elevated fire weather concerns, though winds should have calmed quite a bit by then.

A trough will be positioning itself to our west to impact our storm chances Saturday. In response to the upper level system, surface flow out of the southeast will amplify. Higher quality moisture will be advected in and will be sufficient in allowing thunderstorms to develop. A good amount of machine learning models are highlighting severe weather potential for our area, particularly the Nebraska Panhandle. Inspecting the 12Z GFS does show an environment characterized by uncapped SBCAPE values over 2000 J/kg, EBWD values around 50 knots, and step lapse rates. Such parameters are supportive of supercells with an elevated large hail risk. In addition to severe weather the flooding risk may be elevated given the high perceptible water values nearing an inch or greater for the eastern portions of our area. In addition storm motions do not appear to be particularly fast, generally below 15 to 20 knots. The WPC has introduced a marginal risk for flooding in the northeastern portions of our CWA given the above conditions.

Sunday through Monday keeps our stormy pattern going. The greater shear may be displaced to our south and east to reduce severe weather odds, but the moisture and instability will be present to keep storm potential around until our next dry out.

AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 501 PM MDT Tue Jun 16 2026

High confidence that VFR will prevail into tomorrow, with mainly just a few high clouds over Southeastern Wyoming and Western Nebraska underneath broad NW flow. The main concern throughout the TAF period will be our winds, which will begin to increase after a cold frontal passage shortly before sunrise. Have introduced LLWS into the TAFs mainly for KCYS and KLAR as 700 mb winds increase to 50-60 knots shortly before FROPA. These should have no trouble mixing down to the surface given large-scale subsidence beneath the ridge. In terms of gusts, can expect peak winds of 35-40 knots for KRWL and KLAR, and 30-35 knots for the terminals located east of the Laramie Range. KCDR may briefly gust to 40 knots towards the end of the timeframe.

CYS WATCHES/WARNINGS/ADVISORIES

WY...Red Flag Warning until 10 PM MDT Wednesday for WYZ417-418- 430>433. High Wind Warning from 9 PM this evening to 9 AM MDT Wednesday for WYZ106. High Wind Warning until noon MDT Wednesday for WYZ110. High Wind Warning until 3 PM MDT Wednesday for WYZ116. High Wind Warning from 9 PM this evening to 3 PM MDT Wednesday for WYZ117. NE...Red Flag Warning until 10 PM MDT Wednesday for NEZ434>437.