textproduct: Cheyenne

KEY MESSAGES

- Winds will increase across Southeast Wyoming Tuesday into Wednesday, increasing fire concerns and potential for strong winds in the wind prone areas.

- A High Wind Warning is in effect for the Arlington/Elk Mountain wind prone area from midnight tonight through 3 PM Wednesday.

- Greater precipitation chances return to Southern Wyoming and Western Nebraska into the weekend, confidence in precipitation amounts remains low.

SHORT TERM /THROUGH THURSDAY NIGHT/

Issued at 134 PM MDT Tue Apr 7 2026

Tonight...Visible satellite imagery shows some cumulus development across portions of southeast Wyoming, south of a Rawlins to Torrington line. Not expecting much development from this, though a stray shower or two may develop. Will maintain the inherited Red Flag Warning through early this evening as trends show decreasing humidities and increasing winds. A shortwave trough aloft moving across eastern Montana will send the next cold front into our northern counties late, though with little sensible weather and only a wind shift to the north. Relatively mild overnight with decent low level mixing. 40 to 50 knot 700 mb flow develops after midnight, and based on the local wind model and 850 and 700 mb Craig to Casper height differences, we expect winds to pick up near Arlington and Elk Mountain, though confidence not high enough to upgrade at this time and so will leave the current High Wind Watch in effect.

Wednesday...As the cold front moves further south, with low level upslope developing, temperatures will be somewhat cooler, and 700 mb temperatures near 1 Celsius yielding maximum temperatures in the upper 50s and lower 60s. Will need to keep an eye on winds and relative humidity for Carbon and Albany Counties in the afternoon for elevated fire weather concerns.

Wednesday night...Expecting a cooler night compared to the previous night in the cooler airmass behind the cold front.

Thursday-Thursday night...A warming trend begins as 700 mb temperatures rise to near 4 Celsius. As a shortwave trough moves overhead near peak heating and a low level convergence boundary sets up over our southern counties, it looks like scattered showers should develop in the afternoon and evening south of a Rawlins to Alliance line in the vicinity of a low and mid level theta-e ridge axis. The showers will continue into the evening hours, and then continue over the southern Nebraska Panhandle after midnight.

LONG TERM /FRIDAY THROUGH TUESDAY/

Issued at 134 PM MDT Tue Apr 7 2026

Unsettled weather looks to develop during the long term forecast period with numerous waves of energy and precipitation chances from Friday through Tuesday of next week. The culprit for the persistent active weather will be a large upper-level low pressure system which will move into the Pacific coast and remain generally stationary for several days. Upper-level troughing with lower heights will be the norm across the Rocky Mountain region. Friday will likely be the driest day in the period as the main region of energy and lift remains fairly well to the west. However, increasing mid-level moisture and surface heating will result in low-end instability over the higher terrain of southern Wyoming (around 500 J/kg of SBCAPE) and a few isolated afternoon showers and possibly some thunder will be possible. On Saturday, ensemble guidance is in good agreement showing seasonably high moisture return in the high plains of Nebraska and into far southeast Wyoming. With increasing westerly flow aloft ahead of the upper-level low, surface south to flow, and around 500-800 J/kg of SBCAPE, a few isolated afternoon showers and thunderstorms are possible to the east of the I-25 corridor. While greater moisture return will likely remain well to the south of our region, this overall setup does favor a few isolated stronger storms which may be capable of some of the first small hail (less than 1/2 inch) of the year in the high plains.

Forecast confidence decreases from Sunday onward as the exact details of the movement of the broad upper-level low become quite muddled and varied in ensemble guidance. There is generally good support for continued troughing in the west from Sunday through Tuesday, however a push of slightly drier air on Sunday behind a vort max may help keep the forecast mostly dry this day. Renewed shower and thunderstorm activity is possible on Monday and Tuesday as most guidance brings the core of the upper-level system through the eastern Rockies and High Plains by this time. However, the exact track and strength of any surface cyclogenesis east of the mountains will ultimately determine how much precipitation falls. While drought-busting rains are not likely, precipitation should run above- average in the long term with the potential for most locations to pick up at least a half of an inch of liquid by mid-next-week.

AVIATION /00Z TAFS THROUGH 00Z THURSDAY/

Issued at 552 PM MDT Tue Apr 7 2026

VFR conditions expected over the next 24 hours. Diurnally driven winds will relax tonight with most sites around 10-12 knots and shifting to a more northwesterly to northerly direction by tomorrow. Cloud decks remain high and will clear this evening, with the return of some generally high to occasionally mid based decks, with the lower decks from very weak passing showers primarily near KCYS/KLAR.

CYS WATCHES/WARNINGS/ADVISORIES

WY...Red Flag Warning until 8 PM MDT this evening for WYZ417-418- 432-433. High Wind Warning from midnight tonight to 3 PM MDT Wednesday for WYZ110. NE...None.