textproduct: Cheyenne

KEY MESSAGES

- Mild temperatures return to the region through the weekend as upper-level ridging returns.

- Mountain snow and high winds possible in the wind prones and wind prone adjacent areas of southeast Wyoming on Sunday.

SHORT TERM /THROUGH SUNDAY/

Issued at 253 PM MST Fri Jan 2 2026

A breezy day continues across the forecast area with wind gusts of 35 to 45 MPH this afternoon. High Wind Watches and Warnings remain in effect for the usual southeast Wyoming wind prones, however, they have not verified yet. Decided to keep them going through their expiration time this evening as occasional wind gusts over 50 MPH continue to occur. Winter Weather Advisories for the mountains have verified and performed well, so these should be allowed to expire on time later this afternoon as snow has slowed with only an inch or two of additional snow expected. Besides wind and snow, radar shows light returns over the CWA. Observations report light rain under these echoes as temperatures sit in the 40s and 50s. Showers will dissipate this evening, leading to drier conditions overnight. Overnight lows will still be on the milder side for early January as breezy, downslope winds continue tonight.

A rather pleasant day is expected on Saturday as upper-level ridging builds over the Rockies. 700 mb temperatures will increase above 0C, leading to a mild day across the forecast area. Partly to mostly sunny skies throughout the day will add to the warmth of the day. High temperatures out west will be in the 40s and 50s, while east of the Laramie Range will see highs in the 50s to low 60s. This puts highs anywhere from 15 to 20 degrees above average for this time of year! A weak shortwave moving through the ridge overnight will begin to usher in a bit of mid-level moisture. This, combined with southwest flow, will lead to orographic lift in the Sierra Madre Range, potentially leading to some light mountain snow.

With the shortwave expected to move through Saturday night, another round of high winds will possible. A strong MSLP gradient will develop overnight, leading to winds aloft strengthening. 700 mb winds max out at about 65 kts with strong subsidence to bring these winds down to the surface. This event looks to affect the usual wind prone locations, but could also spread out to affect wind prone adjacent areas like the Interstate 25 corridor from Casper to Cheyenne. In-house guidance is already showing 50 to 60 percent probabilities for high winds late Saturday night and into the day Sunday. High wind headlines will likely be needed if the GFS holds onto these strong winds, however held off on issuing anything for now until the current wind headlines expire.

Sunday will be another warm day as anomalously warm air sits aloft. 700 mb temperatures are in the 90th percentile of NAEFS climatology. These temperatures, combined with warm downsloping winds will lead to highs in the 50s to mid-60s east of the Laramie Range. Temperatures will remain similar to Saturdays highs out west as increased moisture and cloud cover keep temperatures more stable. Cannot rule out a few showers in the high valleys out west during the day, as well as some light mountain snow.

LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/

Issued at 253 PM MST Fri Jan 2 2026

Models are in firm agreement with an upper level low off the coast of California pulling the gradients aloft to a southwest flow Sunday night through Monday before flattening and becoming westerly flow aloft Wednesday. This will bring in some moisture advection from the southwest and west with snow returning to the mountains. Snow will persist across the Sierra Madres and Snowy Range through Tuesday with higher accumulations in the Sierra Madres. Raw ensembles show 70-80% probabilities of 7-8 inches of snow in the Sierra Madres and near 3 inches of snow in the Snowy Range beginning Monday afternoon and persisting through Tuesday afternoon. Models show surface CAPE values of up to 500 J/kg so, not only will there be snow, but deterministic guidance also shows 15% probabilities of thunderstorms across the Sierra Madres between 11 AM Monday through 5 AM Tuesday. Snow will continue through Tuesday afternoon at 11 PM with another round of accumulations of 3-4 inches along the Sierra Madres with 55- 65% probabilities.

Models show a break in precipitation as the upper level flow turns westerly before becoming southwest again Wednesday and bringing in more moisture from the southwest through Friday night. In-house guidance shows snow accumulations from 11 AM Wednesday through 5 PM Friday to be near 11 inches along the ridge line of the Sierra Madres and near 6 inches along the Snowy Range. Guidance also shows the lower elevations could see a skiff of snow as well with 45% probabilities even this far out.

Winds will remain slightly elevated Monday through Wednesday as the 700 mb jet makes slowly makes its way to the east and winds turn more to a southwest flow aloft. 500 mb winds will drop from 70 kts to around 40 kts which will continue to allow mixing at the surface. However, not nearly as strong at the last few events. In-house guidance show winds to be elevated as apposed to high. Raw ensembles shows winds will be primarily diurnally driven with peak gusts between 30-35 mph with some locally higher gusts in some isolated locations (70-80% confidence) As for the areas east of Laramie Range, winds will also be diurnally driven with peak gusts between 25-30 mph and 60-80% confidence. After Wednesday, models begin to diverge and show at least some sort of southwest flow aloft. Raw ensembles and in-house calculations all show the winds to remain diurnally driven and below 25 mph at the surface Thursday and Friday.

AVIATION /00Z TAFS THROUGH 00Z SUNDAY/

Issued at 442 PM MST Fri Jan 2 2026

VFR conditions expected over the next 24 hours. Clouds are lifting and clearing, allowing for either SKC or high level CIGs at FEW to SCT. Breezy winds also subsiding, with some gusty conditions persisting through the next few hours before most sites should see winds 10-12 knots or less through tomorrow evening. The exception will be KRWL where gusty conditions should pick back up tomorrow afternoon.

CYS WATCHES/WARNINGS/ADVISORIES

WY...High Wind Watch until 8 PM MST this evening for WYZ106-117. High Wind Warning until 8 PM MST this evening for WYZ110-116. NE...None.