textproduct: Western and Central Wyoming

KEY MESSAGES

- Cooler today with rain showers and mountains snow showers, with the most numerous showers in western and southern Wyoming. Expect more of the same for Wednesday.

- A weather system crosses the area Thursday and Friday with more widespread mountain snow and rain changing to snow in the lower elevations.

- On Thursday and Friday, the steadiest rain and snow will be in northern Wyoming, but all areas will have some. Accumulating snow is possible in the lower elevations Thursday night and Friday.

UPDATE

Issued at 1234 PM MDT Tue Mar 31 2026

After being in summer weather for some time, we have pivoted back to spring this week. The overall message remains the same for today, with cooler temperatures and rain/snow chances. The forecast through the next 24 hours has been updated to reflect the latest hi-res models, though the showery nature of precipitation makes it difficult. Showers, especially across the southern half of the area tonight into tomorrow morning, may bring varied rain amounts over short distances. Basins have the least chances for precipitation, with up to 0.1 inches, though no rain is also possible. Precipitation chances continue overnight and through Wednesday, with continued active weather to end the workweek.

DISCUSSION

Issued at 250 AM MDT Tue Mar 31 2026

For those of us who are cold weather haters (myself included), this has been a great winter. The problem is that it has been rather dry, and we do need precipitation. Most of the area will be pushed back toward reality, starting tonight, including some well needed precipitation.

The cold front responsible for this is now pushing southward and brought cooler temperatures and a gusty wind, although no high wind right now. It has also brought some precipitation, in the form of both rain and snow. This is mainly across northern Wyoming where some moisture is interacting with a jet streak. Showers are generally falling north of a Jackson to Buffalo line as I write this around 2 am. Webcams show there has been some accumulation, although mainly on grassy surfaces with most roads largely wet at this time. Guidance is in fairly good agreement with most of this tapering off after sunrise, except across the western mountains. As for highlights, none will be issued since most roads would be wet to slushy, and snow would melt fairly quickly today with the almost April sun. A continued feed of moisture will keep showers across the west though. As for precipitation type, snow levels will remain fairly high today. The coldest 700 millibar temperatures get will be minus 2, which would put snow levels above 7500 feet. And even here, travel impacts would be limited with the warm ground and high sun angle melting a lot of the snow. The chance of 6 inches of snow or more is less than 1 out of 3 through Wednesday morning for most areas as well. The exceptions are the far northern Absarokas and the higher peaks of the Tetons, Wind Rivers and Bighorns. With the limited impacts, no highlights will be issued. Other showers should develop across southern Wyoming as the front moves south. Precipitation here would be largely rain though. The other impact will be cooler temperatures, especially in the north where high temperatures 20 to 30 degrees colder will be common.

Reasoning for Wednesday through Friday remains largely the same this morning as it was yesterday morning. Things look cooler and unsettled as troughing moves across the western United States. The steadiest precipitation for most still looks to be on Thursday and Friday as low pressure moving onshore in the Pacific Northwest moves toward Wyoming and crosses the state Thursday night and Friday. However, the thing that has me ripping out more of my thinning hair is there is still disagreement in the details of the placement and timing of the precipitation. On Wednesday, the majority of the showers look to be confined to western Wyoming but model solutions have different placement of the heaviest precipitation. Showers will be more sparse East of the Divide but again, there are different placements of the heaviest QPF. As a result, we kept things largely generic. Temperatures are cooler on Wednesday, but with 700 millibar temperatures remaining largely at minus 3 or higher, snow levels will again be generally 7000 feet or higher so populations centers will see largely rain.

The main event still looks to be Thursday into Friday as the low crosses the area. Guidance has diverged a bit though in the placement, with some members of the guidance trending northward. This would put the heaviest precipitation across northern Wyoming. The National Blend of Models gives a greater than 4 out of 5 chance of 6 inches or more of snow across the northern mountains through this period. The chance of 12 inches is largely restricted to the higher Tetons and the Bighorns. If this track holds true, the one area that could do especially well would be the western Bighorns, which would get snow from the low passing as well as favorable northwest upslope flow with the wrap around moisture behind the low. If I had to pick one location to get over 15 inches of snow, it would be the western Bighorn Range. Highlights will likely be needed but it is a bit too soon for them. As for the lower elevations, rain will change to snow from west to east as colder air wraps in behind the low pressure system. Much of the area has at least a 1 in 2 chance of an inch of snow through Saturday morning, with many areas north of the Owl Creek and Bridger Range having a greater than 2 out of 5 chance of 3 inches or more. Highlights may also be needed here as well but more questionable as impacts on travel may be limited by the warm ground and high April sun angle. The main impacts would likely be at night.

Quieter weather should then return for the weekend as flat ridging builds back over the area. The result will be a return of above normal temperatures and breezy conditions through at least Monday.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1030 AM MDT Tue Mar 31 2026

West of the Divide...KBPI/KJAC/KPNA/KRKS Terminals.

Scattered showers and mountain obscuration prevalent west of the Divide. Only JAC is seeing intermittent showers on station with MVFR conditions expected. Rain showers more likely for BPI/PNA this afternoon after 19Z that will turn to snow after 06Z before rain showers once again Wednesday morning after 13Z. RKS should remain all rain after 06Z through the overnight into much of Wednesday morning along with JAC. A break in precipitation by the the end of the period with another round into the next cycle or two for Wednesday night into Thursday. Otherwise, winds relatively light around the 10kt mark before an increase for PNA/BPI/RKS late Wednesday morning after 17Z.

East of the Divide...KCOD/KCPR/KLND/KRIW/KWRL Terminals.

Light snow and MVFR conditions for COD with low ceilings at all other locations with the colder air in place. These should lift to VFR this afternoon ahead of a more widespread round of rain early Wednesday morning after 09-11Z. A changeover to snow is unlikely at this time with the overcast skies not allowing temperatures to drop as much. Rain shower activity looks to break by the end of the period with another round in the next cycle or two. Winds relatively light around 10kts with ample mountain obscuration for much of the area but especially for COD/LND closer to the Winds and Absarokas.

Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for the latest information on icing and turbulence forecasts.

RIW WATCHES/WARNINGS/ADVISORIES

None.