textproduct: Cheyenne

KEY MESSAGES

- A gorgeous weekend is in store as temperatures rebound into the 50s and 60s with clearing skies and minimal precipitation chances.

- Warmer, drier weather returns for the week ahead, with fire concerns increasing after Monday.

- More unsettled weather pattern may return as early as Wednesday and continue into next weekend.

SHORT TERM /THROUGH SUNDAY NIGHT/

Issued at 245 AM MDT Sat Apr 4 2026

Current IR Satellite loop early this morning shows the departing snow storm moving eastward across the Dakotas and eventually into the Great Lakes region later today. Behind it, brisk northwest winds and some lower clouds remain over southeast Wyoming and western Nebraska. KCYS radar loop not showing much, so snowfall is unlikely this morning outside of the mountains with a few light returns over the southern Laramie Range and the Snowy Range. Gusty winds have come down a bit across the southern Laramie Range with webcams showing improving conditions and little snowfall and/or drifting snow. Will allow the Winter Weather Advisory to expire on time early this morning, at 300 AM, with only some flurries expected until sunrise. Otherwise, not many changes made to today's forecast with sunny skies expected. 700mb temperatures will gradually increase towards 0c across southeast Wyoming, but remain between -4c to -8c across the eastern plains. Forecast highs in the 50s to maybe around 60 below 4500 feet looks reasonable this afternoon with breezy conditions continuing behind the Great Plains storm system. Clear skies should continue into tonight with some high clouds north of Interstate 80, which should result in decent radiational cooling with lows dropping into the 20s for most locations.

Models show dry weather continuing through Sunday as all guidance shows a ridge of high pressure translating eastward out of the eastern Pacific. 700mb temps will climb above 0c through the day, which should result in a pleasant Easter with highs in the low to upper 60s for most locations along and east of the I-25 corridor. Ensemble guidance shows temperatures several degrees lower compared to MOS guidance and high res, likely due to increasing southerly winds...but these should start late enough in the day to not be much of a concern. Kept high temperatures between the 75th to 90th percentile due to mostly sunny skies and light winds. Although the GFS and NAM show some instability near and along the Laramie Range Sunday afternoon with light terrain-induced convergence, limited to minimal boundary layer moisture should greatly limit any potential for daytime convection.

LONG TERM /MONDAY THROUGH FRIDAY/

Issued at 127 AM MDT Sat Apr 4 2026

The work week will begin underneath a mid-level ridge in a WNW flow pattern, resulting in dry and mild conditions with much calmer winds (5-10 knots) relative to what we have seen recently. High temperatures look to be at or slightly above climatology in the mid to upper 50s before the ridge begins to break down into Tuesday and 500 mb flow becomes more zonal. 700 mb flow ramps up to 45-50 knots throughout the day on Tuesday, with omega fields hinting at a classic mountain wave pattern, and therefore downslope flow particularly in the lee of the Laramie Range. Vertical cross sections indicate strong static stability at mountain top as denoted by a tight vertical isentropic gradient, which is another favorable signature for downsloping winds. Despite the dampening ridge, this flow regime will result in high temperatures being 10-15 degrees warmer than the previous day with ensemble guidance showing 50th percentile maximum temperatures pushing 70 degrees east of the I-25 corridor. Given the uptick in surface winds along with ensemble mean RH values at or below 20%, Tuesday will feature fire concerns especially with plenty of dry fuels with our extreme to exceptional drought status. Fire weather highlights and red flag conditions will need to be monitored as we get closer to this time frame.

Mid-level flow will remain zonal into Wednesday, however with a decrease in mountain-top stability and overall weakening 700 mb flow, surface winds look to be more relaxed compared to the previous day. We also introduce PoPs to the forecast at this time with weak impulses embedded in the zonal flow propagating across Southern Wyoming. However the main forcing for ascent will be well to our north over Montana and South Dakota, so any precipitation will be light, with NBM probabilities of seeing QPF > 0.1" running at 20-25% east of the Laramie Range. There is also some weak instability present, however with dry low-levels (surface RH values around 25%), any convection will likely produce far more wind than rain.

Precipitation chances will increase towards the end of the work week followed by a decrease in temperatures as Southern Wyoming and Western Nebraska will be located in the right-entrance region of a 75-80 knot 250 mb jet, as well as downstream of a shortwave trough over the Great Basin. Under SW flow aloft, subtropical moisture will advect into our area, with LREF PWAT values exceeding the 90th percentile relative to climatology into Thursday through Saturday. Given the signal for strong isentropic ascent along with low-level theta-e advection, confidence is increasing that we will finally see some beneficial moisture for much of the area. Probabilities of QPF exceeding 0.25" into Saturday range from 60-70% east of the Laramie Range, with the highest probabilities of exceeding this threshold over the Snowy and Sierra Madre Ranges (around 90%). Expect high temperatures to be slightly cooler than average at this time.

AVIATION /12Z TAFS THROUGH 12Z SUNDAY/

Issued at 550 AM MDT Sat Apr 4 2026

Strong storm system across the northern Great Plains will continue to move northeast into the Great Lakes region today. It will remain breezy behind this system across the high plains through this afternoon.

HAZARDS/WEATHER TRENDS: VFR conditions will prevail today with a few areas experiencing brief SCT low clouds around 2000 feet AGL. Behind the storm system to our east, gusty west to northwest winds will continue until 01z Sunday with gusts up to 30 knots for the southeast Wyoming terminals and gusts around 35 knots for all western Nebraska terminals. These winds will quickly subside around sunset.

CYS WATCHES/WARNINGS/ADVISORIES

WY...None. NE...None.