textproduct: Cheyenne

KEY MESSAGES

- Another strong storm system will bring widespread snow, gusty winds, and blowing snow to much of the area north of I-80.

- A Winter Storm Warning has been issued for Converse county for 4 to 8 inches of snow along with gusty winds and blowing/drifting snow.

- Scattered snow showers and a few snow squalls are expected along and west of the I-25 corridor through this evening. Winer Weather Advisories have been issued for portions of Carbon County.

- Winter Weather Advisories have been issued for much of the remaining areas of the High Plains. These areas can expect a widespread 2 to 6 inches of snow, but localized banding will produce isolated amounts over 6 inches. The exact location of this banding is uncertain.

- Strong winds will return to the wind prone areas behind a cold front Wednesday evening, and continue through Thursday morning.

- Moderate to heavy mountain snowfall is expected to continue through Thursday, mainly above 8500 feet.

- Another storm system may bring light snow to portions of the area on Friday.

- Cold temperatures will continue through Saturday.

SHORT TERM /THROUGH THURSDAY NIGHT/

Issued at 300 PM MST Wed Feb 18 2026

Another strong upper level low pressure system is already moving into the area right on the heels of yesterday's wind and snow squall event. The trough axis is currently over the Great Basin, but plentiful cloud cover is streaming in over the area, keeping today's high temperatures several degrees colder than initial forecasts. The upper level trough is digging in deeply over the western CONUS and developing a slight negative tilt to it. This is producing strong warm air advection aloft (mainly in the 700 to 500-mb layer), despite a surface high pressure bringing in colder air at the surface. The surface front has stalled roughly from a Douglas to Kimball line, and the strongest overrunning lift is currently over the same areas. This is causing radar to fill in across this area, which is several hours ahead of initial expectations. Hi-res models are having a difficult time handling the rapidly evolving setup today, which is resulting in wild swings from run to run. The official deterministic forecast is mostly grounded close to the global ensemble mean for QPF, but there will be locally higher amounts due to mesoscale banding. In addition, strong winds will kick up in the wind prone areas along I-80 behind the frontal boundary. The remainder of the discussion will be broken down by hazard type.

SNOW SHOWERS / SQUALLS: The latest mesoanalysis shows fairly potent instability (for mid February) over Carbon and Albany counties once again, with SBCAPE exceeding 250 J/kg. Extremely steep lapse rates are present through the entire troposphere over the area, generally 8-9C/km which is highly unusual for this time of year. Forcing is not as strong as it was yesterday for snow squalls, but the convective environment is quite potent especially for the time of year. As a result, the snow showers may not be as well organized as what we saw yesterday, but the intensity potential is still certainly there for fairly widespread on and off snow showers with isolated storms reaching into snow squall criteria. In addition, some lightning is certainly not out of the question in these areas this afternoon. Much of Carbon County was added to a Winter Weather Advisory for accumulations of 1-4", but we will be monitoring for Snow Squall Warnings on top of that.

HIGH PLAINS SNOW: Lift is expected to come from low-level frontogenesis with the surface front pushing up against the Laramie Range, combined with continued strong isentropic lift overrunning this boundary. Later this evening ahead of the primary trough axis, expect to find much stronger mid-level frontogenesis moving eastward across the area as a negatively tilted mid-level low rapidly deepens over northeast Colorado. This will be the key to the forecast, as that forcing is expected to provide the focal point for the mesoscale banding, and thus the best potential for 6+ inches of snow accumulation. The best lift is expected to remain over Converse county for a longer period of time, so there was enough confidence to upgrade the Winter Weather Advisory to a Winter Storm Warning there. Elsewhere, the lift looks quite good, but this system is very progressive and the window for snow accumulation is not very long. Without the strong mesoscale banding, it will be hard to get widespread amounts in warning criteria. Additionally, there is significant uncertainty regarding the exact location of the banding, which makes it difficult to decide which location should get an upgrade. Therefore, decided to use a broad Winter Weather Advisory for a widespread 2 to 6 inches of snow, with added wording discussing the potential for localized 6+ amounts. This is a very dynamic storm system rapidly strengthening very close to our area, which always presents the potential for a few surprises. Snow should wind down Thursday morning, but some modest frontogenesis could linger over the northern Nebraska panhandle into the afternoon hours. In addition to the snow, winds and blowing snow will be a concern. Expect east to northeast winds to increase this afternoon and evening north of the stalled frontal boundary, transitioning to northwest behind the trough axis this evening. Gusts of 25 to 35 mph will be quite widespread and isolated gusts to 45 mph can be expected. This will be more than enough to produce areas of blowing and drifting snow which will increase the impacts of this event compared to most events with this amount of snow. Expect areas of blowing snow to continue through much of the day Thursday. Locations that manage to get that 6+ inches of snow may see enough wind to see visibility drop below one quarter mile at times.

HIGH WINDS: While much of the area will be breezy to windy, the high wind threat should be mainly confined to the wind prone areas. Winds are currently SSW over Carbon and Albany counties, but behind the front, expect a quick transition to westerly winds and a rapid increase in speeds. A 700-mb jet will strengthen rapidly through the southern Wyoming gap and into the deepening low pressure system over northeast Colorado. Synoptic models show a short window with 700-mb winds of 50 to 60 knots, and a strong northwest to southeast oriented MSLP gradient through the Arlington and I-80 summit areas. This isn't a very typical surface pressure gradient direction for traditional high wind events, so some usual wind parameters are not as high as they might be otherwise. However, there is sufficient evidence to upgrade the existing High Wind Watches to Warnings as well as add the Arlington area. Potential exists for wind gusts to around 70 mph with blowing snow. Expect winds to gradually weaken Thursday morning but it will remain quite windy through the day.

TEMPERATURES: Much colder air will wrap in behind the storm system tonight. With cloud cover expected to remain over much of the area on Thursday, highs over much of the area will struggle t get out of the teens. A milder airmass will still be present west of the Laramie range with west winds instead of the NNW to the east. This airmass should spill into portions of the I-80 corridor from Cheyenne eastward, leading to highs in the 20s here. Winds will ease Thursday evening while skies clear out, setting the stage for excellent radiative cooling into early Friday morning. Thursday night low temperatures were dropped several degrees below NBM guidance to favor sub-zero values over much of the area, especially those who have fresh snow cover present.

LONG TERM /FRIDAY THROUGH WEDNESDAY/

Issued at 300 PM MST Wed Feb 18 2026

The long term will start off active as a Pacific low, weakening and branching off from the stronger low in western Canada, will swing across the western US through the Four Corners region as a shortwave trough and bring a risk of some light snowfall totals for our southern zones, with a second shortwave passing across our CWA on Saturday and increasing winds to bring breezy conditions for the day. Thereafter, ridging will take back control, bringing back a warming trend that will see temperatures back well above normal to start next week, but another shortwave will try to at least flatten this feature on Tuesday alongside bringing another risk of high winds for the CWA.

The aforementioned Pacific system should be the strongest and most noteworthy feature of the long term to start the period on Friday. The direction and path of this system across the Four Corners region will keep the strongest conditions to our south, but its path will at least graze our region and allow for another quick shot of snowfall for the day. Current totals from the NBM are around a tenth to a half inch, primarily for locations along and just south of I-80, with a few inches possible in the western mountains as well. Probabilities for at least half an inch or more are on the rise though, with the NBM now beginning to show a 30-50% probability for the I-80 corridor, and if the system can track a bit further north then we should have a better shot for at least somewhat noteworthy snowfall. That being said, forcing isn't going to be the best, and PWAT values are coming in around or just under normal, so a lack of more significant moisture is also going limit how much we can squeeze out of this system. But this feature will also help keep our temperatures on the cool side, with another day of sub-freezing highs expected, though a few sites may be able to peak just around freezing for the day. Saturday and Sunday our temperatures rise a few degrees with the approaching ridge, but another quick shortwave also brings a chance at some breezy winds on Saturday. In house guidance though remains unimpressed and the best 700mb winds will be to our north and east through the weekend, so not expecting another high wind event at this time.

Monday temperatures rocket back up as we see the return of 40's and 50's, with some locations back to knocking on the doorstep of the 60's for the day as high pressure does what it's best at. A passing shortwave is currently forecast to try and make a dent in this western ridge, but it's looking like this system will only flatten out a bit at best and just beyond the long term models are indicating more ridging incoming. But for Tuesday the enhanced pressure gradient from this shortwave alongside increased 700mb winds may bring back our high wind highlights for the day. In house guidance is much more favorable for this system, with probabilities already around 50-60% for gusts 58+ mph at our usual wind prone locations. And a slight increase in moisture may also favor a round of precipitation with this system, though with how warm temperatures are expect that outside of the mountains this should be mostly light rain in nature, but we'll take anything we can get at this point. Finally don't expect this shortwave to do much to our temperatures, as highs once again peak in the 40's to 50's with the Nebraska Panhandle expected to see widespread low 60's for the day as well.

AVIATION /00Z TAFS THROUGH 00Z FRIDAY/

Issued at 434 PM MST Wed Feb 18 2026

A system currently moving into and across the region will bring a mixed-bag of flight categories throughout this TAF period. We are in the early stages of snowfall with scattered returns on radar, expect this to continue and fill in this afternoon/evening, lasting through the overnight hours into Thursday morning. All terminals will see snow at varying times and intensity throughout this TAF period. Thus, CIGs and VIS may drop as low as IFR or LIFR in any moderate/heavy snowfall. In addition, expect gusty winds in the 25- 40 knot range. The other thing of aviation concern will be chances of snow squalls, primarily for KLAR, but can't rule out a stray squall elsewhere in southeast Wyoming, not including KCYS, which may bring VIS down to less than 1/2SM along with gusty winds.

CYS WATCHES/WARNINGS/ADVISORIES

WY...Winter Storm Warning until 11 AM MST Thursday for WYZ101. Winter Weather Advisory until 11 AM MST Thursday for WYZ102- 103. Winter Weather Advisory until 5 AM MST Thursday for WYZ104-109- 110-114. Winter Weather Advisory until 8 AM MST Thursday for WYZ106>108. High Wind Warning from 9 PM this evening to 8 AM MST Thursday for WYZ110-116-117. Winter Storm Warning until 5 AM MST Thursday for WYZ112. NE...Winter Weather Advisory from 11 PM this evening to 2 PM MST Thursday for NEZ002-095. Winter Weather Advisory from 11 PM this evening to 11 AM MST Thursday for NEZ003-021. Winter Weather Advisory until 8 AM MST Thursday for NEZ019-020- 096.