textproduct: Cheyenne

KEY MESSAGES

- Marginal Risk of severe weather expected Saturday afternoon with strong gusty winds and small hail being the primary concerns.

- Drier conditions expected Sunday and Monday with a Red Flag Warning in effect for areas east of the Laramie Range.

- There will be a chance of afternoon and evening showers and a few thunderstorms Monday through Friday, with the best chances on Tuesday.

SHORT TERM /THROUGH MONDAY/

Issued at 1213 PM MDT Sat Apr 11 2026

A shortwave ejecting northeast out of the Great Basin region this afternoon will bring scattered showers and thunderstorms to southeast Wyoming and western Nebraska. The shortwave will provide needed lift, while modest mid-level moisture and steep lapse rates help facilitate thunderstorm development. Model soundings show CAPE values typical of what's expected early in the convective season, generally around 500 J/kg. However, the kicker is the inverted-V profiles on the model soundings which provide insight on what to expect today. Daytime heating and west to southwest winds will dry out the low-levels, providing the basis for these inverted-V profiles. These dry low-levels indicate the primary threat in storms this afternoon and evening will be strong, gusty winds. DCAPE values are sub-1000 J/kg for the most part, but are still elevated enough to see at least marginal severe wind gusts around 60 MPH. Cannot rule out small hail in storms as the freezing level remains relatively low this time of year. Main timeframe for storms will be between 2 PM and 8 PM, with storms quickly dissipating later this evening as the shortwave moves into the Dakotas.

Conditions on Sunday will be drier behind the shortwave as weak, but brief ridging builds in. Temperatures will be a few degrees cooler than Saturday, but will remain 10 to 15 degrees above average for mid-April. West to southwest winds will provide downslope across much of the area, drying out the low-levels and leading to fire weather concerns. As a result, went ahead and upgraded the Fire Weather Watch for the eastern half of the CWA Sunday afternoon to a Red Flag Warning. Dry conditions will continue into the overnight hours as an upper-level jet begins to move into the CWA from the southwest. This will support downsloping winds, as well as usher in dry desert air. Overnight humidity recoveries east of the Laramie Range are expected to be poor, with dry conditions expected once again on Monday in the same areas.

Yet another shortwave will attempt to push into the northern Rockies late Sunday night into Monday. Hi-Res guidance shows the potential for a few isolated showers developing overnight Sunday west of the Laramie Range. However, the low-levels remain dry, so its possible that these showers only produce gusty winds and virga per modeled inverted-V soundings. Much of this will also be true on Monday with prominent inverted-V profiles. Further west, it is possible snow showers will develop which could lead to some light accumulations over the high terrain.

LONG TERM /MONDAY NIGHT THROUGH SATURDAY/

Issued at 1213 PM MDT Sat Apr 11 2026

As we move into the middle of next week, the pattern will remain active and progressive, with a series of shortwave troughs moving through Southeastern Wyoming and Western Nebraska. With the forcing for ascent appearing to be weak at this time, in addition to PWAT values around climatology, confidence in seeing any appreciable precipitation is low, which is certainly not what we want to see given our severe to extreme drought conditions across our entire region. In terms of temperatures, highs on Tuesday look to be 5-10 degrees above climatology mainly in the upper 50s and low 60s along and east of the I-25 corridor, with 40s and 50s west of the Laramie Range.

Numerous shortwave troughs embedded in the flow continue to traverse our area Wednesday and Thursday in this progressive pattern. However, the strongest DCVA is progged to be well to our south over Eastern Colorado, so QPF looks to remain spotty and light with amounts generally < 0.1" as suggested by LREF ensemble guidance. Winds are also expected to ramp up on Wednesday morning, with in- house random forest guidance giving both Arlington and Bordeaux 35- 40% probabilities of exceeding high wind criteria. This is due to an enhanced gradient thanks to lee cyclogenesis occurring over Southwestern Nebraska, resulting in 700 mb flow increasing to 40-45 knots. Temperatures are also expected to be mild given the downslope flow regime, with NBM 50th percentile temperatures approaching 70 degrees for our Nebraska counties on Wednesday, increasing to 70-75 degrees on Thursday. It's a little far out at this time, but would not be shocked to see a few 80 degree readings on Thursday as 500 mb heights rise ahead of the next incoming system. Depending on how much moisture we can squeeze out of each weak impulse this week, fire highlights may be needed during the Wednesday-Thursday timeframe given the increase in winds, dry fuels, anomalously warm temperatures, and mean RH progged to be below 20%.

Friday will feature much cooler temperatures behind a cold front moving through Eastern Wyoming and Western Nebraska overnight, so can expect high temperatures to run about 20 degrees cooler relative to Thursday. Week mid-level ridging builds across the area into the weekend, so anticipate a warming trend and dry conditions at this time.

AVIATION /00Z TAFS THROUGH 00Z MONDAY/

Issued at 534 PM MDT Sat Apr 11 2026

VFR conditions are anticipated throughout the TAF period for all of our Wyoming and Nebraska terminals. Expect any remaining showers and thunderstorms to fade within a couple of hours of sunset as daytime heating dwindles. 10-15 knot SW flow will remain in place through 16Z Sunday before wind gusts increase to 25-30 knots, with KRWL seeing occasional gusts of 35-40 knots. Expect most clouds to move out this evening leaving behind just a few high clouds aoa 20 kft.

CYS WATCHES/WARNINGS/ADVISORIES

WY...Red Flag Warning from noon Sunday to 8 PM MDT Monday for WYZ417>419-430>433. NE...Red Flag Warning from noon Sunday to 8 PM MDT Monday for NEZ434>437.