textproduct: Cheyenne

KEY MESSAGES

- Cooler temperatures, though still above average, today behind a surface cold front. Isolated showers possible Sunday and Monday.

- Slow warming trend expected Monday through Wednesday with another round of record high temperatures possible.

- Fire weather concerns will increase Tuesday and Wednesday with increasing westerly winds.

SHORT TERM /THROUGH MONDAY NIGHT/

Issued at 305 AM MDT Sun Mar 22 2026

Current observations this morning across western Nebraska and southeast Wyoming show the surface cold front moving into the high plains of eastern Colorado at this hour. All sites along and east of the I-25 corridor show gusty north to northeast winds and temperatures falling into the 30s. Further west, the depth of the cooler air is pretty shallow, so it has not quite pushed across Albany and Carbon counties just yet. The leading edge of the front is likely moving across far northern Carbon and Albany counties at this time with Shirley Rim reporting 32 degrees and gusty north north-east winds. In contrast, Laramie 60 miles to the south shows a temperature of 48 degrees and westerly winds. Expect the leading edge of the front to slowly drift south into Rawlins and Laramie through sunrise this morning with temperatures around 10 to 15 degrees cooler compared to yesterday. No precipitation has been observed so far, but there are some scattered showers near and west of Rapid City. A few of these showers may pass through Niobrara, Sioux, and Dawes county this morning.

For the rest of today, afternoon temperatures will be around 20 to 30 degrees cooler compared to Saturday across the high plains. However, this is still 5 to 10 degrees above average for this time of the year, so it should remain pleasant with relatively light winds across the region. Lowered POP this afternoon with all models showing limited to no instability and CAPE below 100 j/kg. Warmer temperatures aloft and some cloud cover will likely cap any low level instability present in the boundary layer, so lowered POP below 10 percent through this evening. Still, can't not rule out a few sprinkles or light showers...but virga is more likely in this environment with a pretty dry boundary layer.

Another warming trend begins Monday as a flat ridge of high pressure aloft nudges northward over the Intermountain West. Models show 700mb temperatures climbing above 5c, which generally translates to afternoon high temperatures in the 60s to low 70s...warmest below 4500 feet. Better chance for mountain rain/snow showers Monday afternoon and evening as a 100kt jet max lifts north across the area. With some afternoon instability, widely scattered showers look like a good bet over southern Carbon and Albany counties, possibly extending as far east as the southern Laramie Range. Kept POP between 20 to 35 percent for some mountain snow. Otherwise, most other areas will remain dry with thick mid to high cloud cover. Overnight low temperatures will also be on the mild side due to WAA aloft and cloud cover...generally in the mid 30s to mid 40s.

LONG TERM /TUESDAY THROUGH SATURDAY/

Issued at 245 PM MDT Sat Mar 21 2026

This persistent upper level ridge will keep building over our region going into Tuesday. Record high temperatures may be broken at some of the Wyoming Front Range sites as temperatures are likely to reach the mid to upper 70s, where records currently stand in the low 70s. Winds are also expected to increase as the 700mb pressure gradients begin tightening. Machine learning guidance is still highlighting elevated probabilities to 40 percent of high wind conditions in the wind prone areas. There are also 700 mb shortwaves being shown in model solutions, the passages of which could amplify winds if coinciding with peak mixing daytime hours or any mountain wave breaking.

Overnight Tuesday humidity recoveries will be poor, keeping already desiccated fuel sources receptive to fire spread. The Storm Prediction Center is highlighting a 70 percent Critical probabilities over a large portion of the CYS CWA. The conditions certainly match this outlook going into Wednesday, which looks the most concerning for impactful fire weather conditions so far. Relative humidity values are generally expected to be in the teens and high temperature likely to break records, some by almost 10 degrees.

Our next cold front has slowed down in today's guidance to next Thursday morning and there is notable divergence in its timing and strength. The trough associated with this front is flatter and less amplified in model guidance. The GFS solution is the most bullish in the strength of this front. If this is the correct solution then Friday may be cooler and more seasonable. However, if not, then much will be the same with above average temperatures. We will need to wait and watch guidance for any agreement as we get nearer.

To end this discussion on perhaps a happier note, in the very long term, past this forecast period, sees the possible breakdown of this stubborn ridging pattern. While too soon to work out specifics, ensembles are hinting at the return of the jetstream and wave breaking going into April. Fingers crossed this marks a return of wet and cooler conditions.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1141 AM MDT Sun Mar 22 2026

KBFF and KCDR will start off the forecast period at or near MVFR given the lingering low level cloud coverage around 3,000 ft. This is expected to clear up in the next few hours. At other terminal locations the sky is clearing up with some lingering mid and high level clouds. Winds are expected to be light around 10 knots with occassional gusts to 20 knots out of the northeast at our Nebraska terminals and KCYS. KLAR and KRWL may experience more brisk conditions with some gusts reaching 30 knots out of the north or northwest. Overnight increasing cloud coverage is expected and gusty winds out of the south/southeast associated with the development of a low level jet. This may push winds into the 30 to 40 knot range across the Nebraska Panhandle terminals. Lowered ceilings are also possible with scattered occurances of 8-10,000 foot ceilings.

CYS WATCHES/WARNINGS/ADVISORIES

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