textproduct: Cheyenne

KEY MESSAGES

- Red Flag Warning for portions of southeast Wyoming for gusty winds, low relative humidities, and dry lightning from 12 pm through 9 pm Tuesday Night.

- Severe weather chances should mostly remain just northeast of our area on Tuesday, though gusty showers or virga will be possible still, with a more widespread severe threat expected on Wednesday as we undergo a pattern change.

- Cooler on Wednesday and especially for Thursday through Saturday, with increasing chances for afternoon and evening showers and thunderstorms each day and a rising excessive rainfall threat.

SHORT TERM /THROUGH WEDNESDAY NIGHT/

Issued at 300 AM MDT Tue Aug 11 2026

For the short term, Tuesday will mark the last day we should see largely similar conditions as we've experienced over the past several days, with warmer than average temperatures and another round of dry thunderstorms with stronger activity possible moving into the Nebraska Panhandle. But on Wednesday we'll begin to undergo a pattern change as monsoonal moisture returns to the region, bringing heightened shower and thunderstorm chances along with a re-ignited severe weather threat.

Today, expect one final hit of super warm conditions as we remain around 10-12 degrees above normal with widespread highs in the upper 80's to very low 100's. A dry surface will bring a twofold of threats today however - a critical fire weather environment and dry, gusty thunderstorms. A Red Flag Warning has once again been issued for most of southeast Wyoming due to breezy conditions, relative humidity values into the teens, and the aforementioned dry thunderstorms. While portions of the region, mainly the mountainous zones, may not hit low enough RH values, the dry lightning threat will continue to promote a critical environment. On the note of these thunderstorms, a dry surface layer will continue to produce an inverted V sounding profile, with DCAPE values in the 1000-1500 J/kg range. Expecting another risk of gusty virga showers with little to no rain and near severe level wind gusts. Into the Nebraska Panhandle the environment should be slightly more impressive as MUCAPE values during the start of the afternoon will be similar to the expected DCAPE, but will begin retreating northeastwards into the later afternoon and evening with the stalled boundary that will also move just out of our area. That being said, some CAMs are still developing a stronger storm or two for our northeastern zones in the Panhandle, and with how the past several days have gone it wouldn't be surprising if we had another severe warning or two tonight for this area.

Into Wednesday the high that has been controlling our weather pattern will shift eastwards, allowing monsoonal flow to return and fueling moisture and cooler temperatures. While we won't see a wild swing of highs, overall temperatures will drop by around 5 to 8 degrees, bringing afternoon temperatures into the 80's to low 90's and closer to normal. Meanwhile the increase of moisture will mean an increase to both precipitation and thunderstorm chances. PWAT values will be around 130-160% of normal, roughly around 1-1.5 inches. At the surface, a backdoor cold front will descend down and stall out across our region, while an upper level shortwave is expected to ride the periphery of the ridge across the area with this combination fueling some veering wind profiles and bulk shear in the 30-50 knot range. CAM's indicate two rounds of precipitation off of this - an initial round as the first batch of moisture arrives during the very beginning of the afternoon, with more development forming off of the high terrain to our southwest in Colorado and then lifting up during the late afternoon and beginning of the evening as a large complex of rain and thunderstorms. Any thunderstorms will be capable of large hail and damaging wind gusts, and with multiple rounds of precipitation expected, any training thunderstorms could bring a marginal risk of flooding (particularly from dry and possibly hydrophobic ground). The NBM has a 20-60% probability of greater than or equal to a half inch of new precipitation from just along the Wyoming border through the Nebraska Panhandle, and while not an absolute drenching, with how little we've seen over the past several weeks that rainfall will be beneficial to say the least, as long as it doesn't fall too quickly.

LONG TERM /THURSDAY THROUGH MONDAY/

Issued at 211 PM MDT Mon Aug 10 2026

Thursday evening starts off this long term period with monsoonal moisture moving in, and a shortwave moving through the area. With precipitable water values in the 1-1.5 range, RH values 60-90%, and the shortwave, its safe to say our area will be getting some much needed moisture. This moisture sticks around through Monday, bringing daily afternoon chances of precipitation. This precipitation looks to mainly be showers, but an isolated thunderstorm cannot be ruled out especially near the NE panhandle with CAPE values near 1000J/kg. Winds do not appear to be out of the ordinary, staying below 15 knots most of the time. Temperatures cool off as a cold front moves over the area Thursday. 700mb temperatures stay near 12C during the daytime Thursday-Sunday, with nighttime temperatures getting near 10C. This means temperatures will cool off nearly 20F from what we have been experiencing. Typically our area has daytime temperatures near 83F this time of year. This is a welcomed break from our hot temperatures the last few weeks. With all of this monsoonal moisture coming in, fire weather is not a concern through this long term period.

AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/

Issued at 530 AM MDT Tue Aug 11 2026

VFR conditions expected over the next 24 hours, with CIGS at mid to high levels or SKC through the period. Winds for WY terminals generally westerly, with a northwesterly turn expected into the afternoon, and then KRWL/KLAR may see a shift back to southwesterly by the evening hours. Winds for NE terminals a bit more variable due to nearby boundaries, though a push from the west to northwest during the afternoon is expected. Once again chance of thunderstorms near terminals with gusty winds, erratic winds possible, and dry with little rain. Stronger storms may be possible near KCDR, with low confidence in storms reaching KBFF or KAIA, therefore not listed in TAF at this time.

CYS WATCHES/WARNINGS/ADVISORIES

WY...Red Flag Warning from noon today to 9 PM MDT this evening for WYZ417>430. NE...None.