textproduct: Cheyenne

KEY MESSAGES

- Fire danger will remain elevated to near-critical through at least Tuesday.

- A High Wind Watch has been issued for southeast Wyoming, mainly along and west of the Interstate 25 corridor.

- Moderate to heavy mountain snowfall is expected from Tuesday through Thursday this week, mainly above 8500 feet. A Winter Storm Watch is in effect for the Snowy and Sierra Madre Ranges.

- Snow squalls possible west of the Laramie Range Tuesday morning with the passage of a cold front.

- Snowfall is possible over the Plains Wednesday into Thursday, followed by temperatures falling below seasonal averages for the end of the week.

SHORT TERM /THROUGH TUESDAY NIGHT/

Issued at 259 PM MST Sun Feb 15 2026

MONDAY WILL BE THE CALM BEFORE THE STORM AS THE EFFECTS OF THE UPPER- LEVEL RIDGE WILL STILL BE FELT. 700 MB TEMPERATURES WILL STILL BE ABOVE 0C, WHICH IS ROUGHLY THE 90TH PERCENTILE FOR NAEFS CLIMATOLOGY. THIS WILL LEAD TO A MILD DAY ACROSS THE FORECAST AREA. HIGHS WILL RANGE FROM THE 50S OUT WEST, TO 60S EAST OF THE LARAMIE RANGE. THESE HIGHS ARE ROUGHLY 20 DEGREES ABOVE AVERAGE FOR MID- FEBRUARY. WITH A JET STREAK OVERHEAD, EXPECT TO SEE SOME MID TO HIGH LEVEL CLOUD COVER OVER MUCH OF THE CWA. THIS JET STREAK WILL ALSO LEAD TO BREEZY CONDITIONS FOR MOST OF THE AREA.

BY MONDAY EVENING, A SHORTWAVE WILL BEGIN TO SWING INTO WYOMING. THIS SHORTWAVE WILL BRING BOTH PRECIPITATION AND WIND, HOWEVER THE WIND WILL ARRIVE FIRST. HIGH WIND WATCHES WERE ALREADY IN EFFECT FOR MUCH OF SOUTHEAST WYOMING WITH THE PREVIOUS FORECAST PACKAGE, BUT NEWEST MODEL GUIDANCE SUGGESTS AN EARLIER START TIME TO SOME OF THESE WATCHES. BUMPED THE START TIME UP TO MONDAY EVENING FOR SOME OF THE CARBON COUNTY ZONES AS SOUTHWEST WINDS ALOFT RAPIDLY INCREASES UP TO 55 KTS WITH GOOD SUBSIDENCE. KEPT THE MONDAY NIGHT/EARLY TUESDAY MORNING START TIME FOR THE OTHER WATCHES AS MSLP AND CAG TO CPR HEIGHT GRADIENTS ARE SLOW TO STEEPEN. DESPITE THIS, WINDS ALOFT WILL RAMP UP TO 60 KTS BY TUESDAY MORNING IN THE STRONG SOUTHWEST FLOW OF THE INCOMING JET STREAK.

BY TUESDAY MORNING, THE COLD FRONT ASSOCIATED WITH THE SHORTWAVE WILL ARRIVE IN CARBON COUNTY. PRECIPITATION IS EXPECTED WITH THE FRONT, WITH HI-RES MODELS LIKE THE HRRR SHOWING MORE SHOWERY/CONVECTIVE PRECIPITATION OUTSIDE OF THE HIGH TERRAIN OUT WEST. A QUICK LOOK AT MODEL SOUNDINGS DOES INDICATE A DECENT AMOUNT OF INSTABILITY PRESENT FOR FEBRUARY. COMBINED WITH THE ALREADY PRESENT STRONG BACKGROUND WINDS EXPECTED, SNOW SQUALLS WILL BE POSSIBLE. MODELED SNOW SQUALL PARAMETERS ALSO SUPPORT THE NOTION THAT SQUALLS WILL BE POSSIBLE. THE MAIN AREA OF CONCERN FOR SNOW SQUALLS WILL BE WEST OF THE LARAMIE RANGE DURING THE MORNING HOURS ON TUESDAY. WITH STRONG DOWNSLOPING WINDS PRESENT EAST OF THE LARAMIE RANGE, HI-RES GUIDANCE SHOWS PRECIPITATION DRYING OUT BEFORE IT EVEN REACHES THE INTERSTATE 25 CORRIDOR. SNOW ACCUMULATIONS FOR THE HIGH VALLEYS OUT WEST WILL LIKELY BE FAIRLY MINIMAL FROM SQUALL/SHOWER ACTIVITY, HOWEVER CANNOT RULE OUT A QUICK INCH FROM BRIEF MODERATE TO HEAVY SNOW. WHILE THE BULK OF SHOWER ACTIVITY LOOKS TO BE DONE BY TUESDAY AFTERNOON, MOUNTAIN SNOW WILL PERSIST THROUGHOUT THE DAY. TUESDAY MORNING WILL ACTUALLY MARK THE START OF A PROLONGED PERIOD OF MOUNTAIN SNOW FOR THE SNOWY AND SIERRA MADRE RANGES. MOIST, SOUTHWEST UPSLOPE FLOW WILL AID IN STEADY LIGHT SNOW THROUGHOUT THE DAY TUESDAY. FOR NOW, WENT AHEAD AND ISSUED A WINTER STORM WATCH FOR THESE MOUNTAINS STARTING TUESDAY MORNING AND CONTINUING THROUGH EARLY THURSDAY MORNING. SNOW AMOUNTS ON TUESDAY COULD REACH UP TO 6 INCHES IN THE MOUNTAINS.

BESIDES THE PRECIPITATION, HIGH WINDS WILL CONTINUE INTO THE DAY TUESDAY. WENT AHEAD AND ADDED A FEW ADDITIONAL ZONES TO THE EXISTING HIGH WIND WATCH, INCLUDING THE SOUTH LARAMIE RANGE, FOOTHILLS, AND CENTRAL LARAMIE COUNTY. IN-HOUSE GUIDANCE SHOWS FAIRLY HIGH PROBABILITIES FOR THESE LOCATIONS HITTING HIGH WINDS, BUT EXTREMELY STRONG SUBSIDENCE WILL ALSO EXIST IN THESE AREAS WHICH WILL HELP GET 50 TO 60 KT WINDS DOWN TO THE SURFACE. ARGUMENTS COULD BE MADE FOR POSSIBLE WATCH EXPANSION FURTHER EAST INTO THE PANHANDLE WITH 60 KT WINDS ALOFT AND GOOD LOW-LEVEL SUBSIDENCE. HOWEVER, THE PLACEMENT OF THE 250 MB JETSTREAK PUTS THE CWA IN AN AREA OF LARGE SCALE ASCENT WHICH COULD POTENTIALLY MAKE IT DIFFICULT FOR HIGH WINDS TO REACH THE SURFACE IN AREAS FURTHER EAST. REGARDLESS OF IF THIS HAPPENS, A VERY WINDY DAY IS STILL EXPECTED ACROSS THE PLAINS. WINDS WILL LIKELY EASE TUESDAY EVENING AS THE SHORTWAVE PUSHES OUT.

LONG TERM /WEDNESDAY THROUGH SUNDAY/

Issued at 259 PM MST Sun Feb 15 2026

A train of progressive troughs moving across the Rockies from the Pacific this week will keep active weather continuing through Friday or Saturday, before mild weather and ridging begins to make a return by Sunday.

On Wednesday morning, the area will be in between systems as the first wind storm moves out across the northern Plains. The second trough will be another powerful Pacific trough rapidly moving inland during the middle of the week. Cloud layer RH and mean wind show moist orographic lift continuing in the mountains even in between the troughs, suggesting there may not be much of a break in mountain snowfall, though rates will certainly decrease for a period of time. Much of the area should see a break from the winds Wednesday morning with a reduced cross-barrier height gradient setting up in between troughs. In addition, the departing first trough will drop a surface high pressure over the Montana plains, and the edge of this features will try to creep into our northern zones. While we are not expecting this to manifest as an actual arctic frontal boundary for our area, the increased surface pressure spreading down the I-25 corridor should help provide at least a temporary break from the strong winds. The strong subtropical jet streak out ahead of the primary trough moving across the Great Basin on Wednesday will have noticeable diffluent flow aloft, supporting rapid pressure falls just in the lee of the mountains during the day and evening on Wednesday. Winds will gradually increase through the day again, particularly west of I-25, as surface pressure falls and lee cyclogenesis occurs. Expect to find a stalled frontal boundary somewhere over the area, which as of now appears most likely to set up along the North Platte River Valley. North/east of this boundary, we will see lighter upslope flow, while stronger south to southwest winds can be expected south/west of the boundary.

The primary surface low is expected to develop over northeast Colorado (a rare positioning for this winter season). However, a secondary surface low over southwest or central Wyoming will keep southwest winds in place over Carbon, Albany, and possibly Laramie county, keeping winds elevated here. We will have the low-level upslope flow in place north of the stalled boundary, and forcing aloft looks to improve Wednesday afternoon and evening as isentropic lift kicks up in advance of the approaching trough. This system will be quite progressive, and thus the window for snowfall is not very long, but we have several lifting mechanisms present including those mentioned above, plus vorticity advection aloft, and strong frontogenesis. This will help spread snowfall out into the High Plains Wednesday late afternoon into early Thursday morning.

This system has the potential to be the first widespread accumulating snow event of the year, but some portions of the forecast area will still probably miss out once again. Highest confidence in impactful snow accumulation (in addition to the mountains) at this time is along the US-20 corridor from Douglas to Chadron, and along the I-80 corridor in Carbon county. Based on ratios of about 15:1, the median ensemble member has over 2" of snow falling in both Douglas and Chadron with about 25% of members over 4" of snow. Further west, there is medium confidence in snow impacts too, but the characteristics will be different. The isentropic lift and thus the stratiform valley snowfall will probably not make it into Carbon county, but forecast soundings show very steep lapse rates through the entire troposphere near Rawlins Wednesday afternoon. In addition, strong mechanical forcing is expected as the secondary surface low over central Wyoming gives into the primary low over northeast Colorado. As this occurs, expect rapid increases in surface pressure as the frontal boundary sweeps in from the west. As a result, Wednesday will probably bring another chance for convective snow showers and possibly snow squalls to Carbon county. Snowfall in Laramie will depend on the ability of the convective snow showers to continue east of the Snowy Range, which is a little more uncertain than Rawlins. Probabilities for 1" of snow are around 40% at this time. The I-80 corridor from Cheyenne eastward is the most likely area to miss out on this snow event. Southwest winds in the early phases of the event transitioning to westerly winds later are rather unfavorable. There is a scenario supported by about 25% of ensemble members with a stronger, more southerly upper level trough which would allow for the isentropic lift to set up further south and include the Cheyenne area, but this is not the most likely scenario at this time. Median 24-hour QPF for Cheyenne is only 0.02", which would just be a dusting to a half inch of snow. The model mean is skewed somewhat by a small handful of high outliers.

Once the upper level trough axis swings through late Wednesday evening, we will see rapid dry air advection into the I-80 corridor, along with another increase in wind speeds. Due to the cold front and surface high pressure over the High Plains, this round of wind will likely be confined to areas west of I-25 (though can't rule out gusts of 60+ mph creeping into the Cheyenne area). In-house guidance is depicting around a 50% chance for high winds in the Arlington/Elk Mountain and I-80 summit areas Wednesday evening into early Thursday morning. Expect a cold and windy day on Thursday, which could lead to blowing snow concerns in areas receiving snowfall on Wednesday night. However, the probability for high winds is fairly low (10% for the High Plains).

Models are beginning to pick up on one final trough in this train moving through the area around the Friday or Friday night time period. This one looks weaker than the two preceding systems, and without as strong of a moisture tap to the Pacific. Nonetheless, recent ensemble guidance is trending a little bit more aggressive on precipitation, primarily for the mountains. This may bring another chance for some light snow over the Plains and strong winds in the wind prone areas in its wake. Ensembles are in good agreement showing strong ridging beginning to build back into the area by Sunday supporting another warming trend.

AVIATION /00Z TAFS THROUGH 00Z TUESDAY/

Issued at 426 PM MST Sun Feb 15 2026

VFR conditions expected for the forecast period. Wind gusts will ease over the High Plains overnight, but RWL will remain gusty, and LAR is expected to develop some LLWS when the surface winds die down.

Southwest winds gusting 30 to 40 knots will pick up again Monday morning for RWL and LAR. Winds will shift to the south for all High Plains terminals and begin gusting 15 to 25 knots around midday.

CYS WATCHES/WARNINGS/ADVISORIES

WY...Red Flag Warning until 5 PM MST this afternoon for WYZ417-418- 428>433. High Wind Watch from late Monday night through Tuesday evening for WYZ101-106-107-115>118. High Wind Watch from Monday afternoon through Tuesday evening for WYZ104-109. High Wind Watch from late Monday night through Tuesday evening for WYZ105-110-111-113. Winter Storm Watch from late Monday night through late Wednesday night for WYZ112-114. NE...Red Flag Warning until 5 PM MST this afternoon for NEZ434>437.