textproduct: Cheyenne

KEY MESSAGES

- Snow showers will return to the mountains and adjacent valleys Saturday, spreading into portions of the High Plains Saturday night.

- A strong cold front Saturday night will bring more winter-like temperatures back to the area for Sunday. Well below average temperatures are expected with low temperatures in the single digits possible.

- Gradual warming trend Monday through Wednesday with periods of very windy conditions across the wind prone areas of southeast Wyoming.

SHORT TERM /THROUGH SUNDAY NIGHT/

Issued at 312 PM MST Sat Dec 27 2025

Snow continues out west with webcams along Interstate 80 between Vedauwoo and Rawlins showing falling and accumulating snow. Hi-Res guidance shows these snow showers continuing through the afternoon hours, becoming more widespread across the CWA by the time the evening rolls around. High valleys and foothills out west can expect to see an additional 1 to 3 inches of snow by tomorrow morning. The mountains are expected to pick up an additional 4 to 8 inches by the morning, with winter headlines still looking on track. Snow totals have trended down for the High Plains and areas east of the Laramie Range overnight. This is likely due to the timing of the arctic front expected to drop in from the north overnight. Hi-Res guidance shows most of the precipitation falling during the evening hours for the High Plains. However, for most of this window, temperatures will likely be warm enough for rain. The switchover to snow looks to be after 8 PM once the arctic front is through most of the CWA. Hi-Res as well as GFS and ECMWF ensemble members roughly show a dusting of snow for most areas east of the Laramie Range. The exceptions to this would be Douglas, Chadron and other areas on the north side of the Pine Ridge. Northerly flow behind the arctic front could enhance snowfall totals to over an inch in these locations. Keep in mind, snow totals could be higher than a dusting if the front moves in quicker. Hi-Res guidance shows most of the precipitation done by midnight, however a few snow showers could linger into Sunday morning.

A much colder day is expected on Sunday behind the front. Clouds will clear out relatively quickly during the morning, leading to a mostly sunny day. Despite the sunny skies, temperatures will still be well below average as 700 mb temperatures drop down to -18C during the day. Highs will only be in the teens and 20s, with wind chills in the single digits. Blustery northwest winds are expected behind the front, leading to the cold wind chills. High winds will also be possible for the South Laramie Range and foothills as a strong MSLP gradient develops just south of the Colorado border, leading to 700 mb winds increasing up to 55 kts. Strong subsidence could drive these winds down to the surface, with in-house guidance suggesting a roughly 50 percent chance of high winds occurring. Went ahead and issued a High Wind Watch for the South Laramie Range and foothills Sunday afternoon. Opted for a Watch instead of a Warning for now as high winds are not common out of the northwest. If high winds do occur, it will be a brief window during the afternoon and early evening hours. Winds will weaken overnight, with clear skies leading to an exceptionally cold night with lows in the single digits and potentially below zero in the high valleys with snow cover.

LONG TERM /MONDAY THROUGH SATURDAY/

Issued at 312 PM MST Sat Dec 27 2025

Not much to talk about as conditions across the CWA will be pleasant under ridging that will slide in and dominate weather conditions for most of the long term period. So, lets dive in a bit deeper, at the start of this forecast period, a robust upper-level high at 500mb sits off of the California Coast while a deep low is parked over the Great Lakes region, this keeps dry northwest flow pouring into our CWA. As we progress, the low over the Great Lakes slides east while the high and associated ridge pushes across the Intermountain West into our region by Wednesday afternoon. This continues dominates our weather here locally on Thursday and most of Friday. Then, some things begin to change with a shortwave diving south late Friday afternoon. In-house guidance has a few differences in solutions, primarily with placement and timing of this shortwave, but this is something to watch heading into next weekend due to the possible pattern change. At the surface, not much to write home about with high pressure dominating, keeping weather conditions across the CWA benign for a large chunk of this long term period. As mentioned previously, with the shortwave aloft diving south late Friday, this may increase chances of precipitation for next weekend. So, in the meantime, expect these abnormal conditions to continue, especially with high temperatures, as they soar back into the 40s and 50s, some locations may top out in the low 60s, with the warmest temperatures east of I-25, along with minimal to no precipitation chances. Winds, which have been hammering our known wind prone areas over the previous several weeks, we will get a reprieve from any major events through next weekend.

AVIATION /00Z TAFS THROUGH 00Z MONDAY/

Issued at 445 PM MST Sat Dec 27 2025

Model guidance doesn't have a great idea how the system will evolve but the arctic front should provide a second burst of snow showers between 03-06z for the Nebraska Terminals and maybe for the wyoming terminals. By 12z the snow showers should be done for all terminals and the winds will start to pick up by 15z. By 15z every site should be VFR with mid to high based ceilings.

CYS WATCHES/WARNINGS/ADVISORIES

WY...High Wind Warning until 8 PM MST this evening for WYZ107. Winter Weather Advisory until midnight MST tonight for WYZ110- 111-113-114. Winter Storm Warning until 5 AM MST Sunday for WYZ112. High Wind Watch from Sunday morning through Sunday evening for WYZ116-117. NE...None.