textproduct: Cheyenne

KEY MESSAGES

- Winter Weather Advisories have been issued for the Sierra Madre, Snowy, and North Laramie Ranges, as well as the I-80 Summit and Arlington area today and tonight through 5 PM Tuesday.

- Another round of accumulating snow is expected Thursday morning through Saturday morning. Exact accumulations uncertain at this time.

- Upper-level blocking pattern may start this weekend, leading to the potential for multiple rounds of precipitation across the region.

SHORT TERM /THROUGH WEDNESDAY NIGHT/

Issued at 304 AM MST Tue Mar 3 2026

Rain and snow showers continue early this morning as a shortwave pushes into the forecast area. Current observations show temperatures above freezing for most location, with many ASOS across the CWA reporting rain. SNOTELs in the Sierra Madre and Snowy Ranges are just beginning to pick up accumulating snow, while webcams around the Arlington area show a mix of rain and snow. Patchy fog has also been popping up around the CWA, with this likely continuing through the morning hours.

Precipitation will become more widespread and stratiform as the morning progresses. The shortwave will dive south into Colorado, leaving the bulk of precipitation to fall along the Interstate 80 corridor. Decent precipitation amounts are expected, including some accumulating snow. Snow accumulations will mainly be in the high terrain as well as the plains/valleys west of the Laramie Range. Winter Weather Advisories are in place for the Snowy, Sierra Madre and North Laramie Ranges through the afternoon. The Snowy and Sierra Madres will see the most accumulation, with over 10 inches of snow possible. Winter Weather Advisories are also in place for the Arlington area and South Laramie Range with up to 6 inches of snow possible. Will have to keep an eye on areas like Laramie as prolonged northerly flow could lead to enhanced snowfall amounts during the day. For the most part, areas east of the Laramie Range will be warm enough to see mostly rain. The exception to this would be Cheyenne. Some models like the HRRR, show a few inches of snow accumulation due to prolonged upslope flow. Other models like the GFS and ECMWF, show about a dusting as both the air and ground will be too warm. Trended snowfall totals for Cheyenne near an inch to account for any accumulation that may happen. However, given the warm overnight temperatures, higher accumulations are not likely. Showers will gradually taper off later in the afternoon, leading to a quiet but chilly overnight.

Once the shortwave is out of the area, temperatures will quickly warm up above average once again. Upper-level ridging will take the place of the shortwave, leading to mild and dry conditions on Wednesday. Temperatures west of the Laramie Range could be a bit cooler than currently forecast as this will depend on snow cover, but areas east of the Range will likely see highs in the 50s and 60s. Sunny skies are expected during the day, meaning minimal precipitation chances.

LONG TERM /THURSDAY THROUGH MONDAY/

Issued at 221 PM MST Mon Mar 2 2026

In the wake of our system earlier in the week, our area will briefly be under the influence of a shortwave ridge, bringing us well-above average temperatures with a chance for some light precipitation ahead of the next incoming system. High temperatures will likely exceed 60 degrees east of the Laramie Range, with 50s west of the I- 25 corridor. Models actually have some weak instability progged primarily over our Wyoming counties, so any precipitation may be more convective in nature. Lee cyclogenesis will take place on Friday downstream of a vigorous shortwave trough digging across the Four Corners region, with an associated front impacting SE Wyoming and W Nebraska during the day, resulting in a 20-25 degree drop in high temperatures relative to the previous day. For once, our temperatures will actually be cooler than average, so enjoy the brief taste of winter while it lasts. Given our location relative to the vorticity maxima associated with the 500 mb closed low (resulting in differential cyclonic vorticity advection) along with progged 700 mb frontogenesis, we expect that precipitation will be rather widespread and likely in the form of snow given the post- frontal air mass.

As we head into the weekend, we remain in a cold advection regime under northerly flow, resulting in another day of below-average temperatures and blustery conditions. We will be in the left- entrance region of a 110 knot 250 mb jet, therefore large-scale subsidence and dry conditions are expected at this time. On Sunday, 500 mb heights rise as a zonally-oriented ridge (weird, right?) builds on the eastern periphery of a mid-level anticyclone located off the California coast. This should result in a warming trend into early next week, which will also be accompanied by an increase in our winds. 700 mb cross-barrier flow is progged to exceed 50 knots, with supporting guidance from an in-house wind product suggesting greater than 60% probabilities of Arlington meeting high wind criteria. Details will become more apparent as we get closer in time to this event, but generally the trend is towards warmer, drier, and windier conditions after a brief cooldown heading into this weekend (which will hopefully involve some beneficial moisture).

AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/

Issued at 452 AM MST Tue Mar 3 2026

Tricky aviation forecast for Tuesday with multiple bands of precipitation moving across the area. Southeast Wyoming terminals will likely see snow and/or a rain/snow mix with accumulations possible. Snow will cause IFR conditions with poor visibility as well as low CIGs. MVFR conditions are expected at Nebraska panhandle terminals as rain reduces visibility and potentially lowers CIGs. Conditions across the area will gradually improve this afternoon.

CYS WATCHES/WARNINGS/ADVISORIES

WY...Winter Weather Advisory until 5 PM MST this afternoon for WYZ103-110-112-114-116. NE...None.