textproduct: Western and Central Wyoming

KEY MESSAGES

- An area of snow will move across central Wyoming this evening before moving out of the area after midnight. Up to an inch of snow is possible (30%) with this area of snow.

- Isolated light snow showers may persist tonight in central Wyoming. Little snowfall accumulation is expected.

- Cold temperatures return to the Cowboy State overnight with a brief lull in activity expected for Saturday before another system takes aim at the state for Sunday.

- Another weather system is on the way for Sunday into Monday. Timing and impacts still remain unclear, but there does look to be moderate chances (50-70%) for widespread precipitation.

UPDATE

Issued at 110 PM MDT Fri Apr 24 2026

Well, all it took was a few slight deviations in the forecast and things went from looking dry to a winter wonderland. There were three key components that really shifted the forecast; first was a potent moisture packed upper level jet, second was northerly/northeasterly flow at the surface up to 4,000 feet, and lastly a cold front that stalled slightly farther north then originally expected. All three of these factors were enough to shift forecasted snowfall amounts for the Wind River Basin of a trace-0.5 inches to 2-4 inches with localized areas nearing 5 inches. Nearly all locations north of the cold front, which currently sits across northern Sweetwater County, saw a period of snowfall overnight. Morning snowfall reports show a few inches across the Bighorn Basin with Cody seeing amounts of 2 to 5 inches. Other locations across central and northern WY saw amounts ranging from 1 to 4 inches. As mentioned earlier, all it takes is a few slight deviations in the forecast and there can be a drastic change. Overall, I'm sure not many are complaining, as this is the first measurable snowfall in over a month and travel impacts were minimal as roads saw little to no snow accumulation.

Now for the forecast update, a few changes in the forecast compared to the previous discussion. Today looks a little more unsettled than originally thought. The strong upper level jet continues to streak across the state aiding in the development of scattered showers. The main focus will be on quick bursts of snow that could rapidly drop visibility and make travel a bit difficult at times. Depending on how much sunshine is able to break through the cloud cover, a few isolated rumbles of thunder cannot be ruled out. These squalls will be periodic through the afternoon and evening across nearly all of the state with the best chances (40-70%) being across central and northern WY. There is one thing to monitor and that is a push of moisture late today into the early morning hours Saturday. The main concern looks mostly confined once again to portions of Fremont and Natrona Counties. Hi-res models are showing a rather intense band of precipitation moving across the area bringing a burst of moderate snowfall. The timing of this is still in the air with some models showing it arriving slightly earlier in the evening, while others hold off until late tonight into the early morning hours Saturday. Any additional snow accumulation will be very limited during the daytime today with the best chances arriving after sunset. Similar to this morning, any snow accumulation that occurs this evening into Saturday morning will be mainly restricted to grassy surfaces. Probabilistic guidance is showing a 30-60% chance of an additional 0.5 inches of snow accumulation by Saturday morning across much of Fremont and Natrona Counties. However, if this intense band of snow does develop, its possible some locations may see an inch or possibly two on grassy surfaces by sunrise Saturday.

Temperatures look to be on the chilly side for tonight with lows likely getting into the low teens west of the Divide and low 20s to possibly upper teens east of the Divide. Saturday will see skies gradually clear out with the exception being central WY where low clouds may linger. If this does occur, temperatures will likely remain on the cooler side. Currently, the forecasted highs range from the upper 40s to lower 50s east of the Divide and upper 40s west of the Divide. As mentioned earlier, temperatures could be cooler if clouds do persist. Saturday is looking slightly quieter with a few stray showers possible during the afternoon mainly across higher elevations. Focus will then shift to an incoming disturbance that has the chance to bring another round of widespread precipitation. The timing of this system would be early Sunday through Monday with chances for accumulating high elevation snow and possibly some rain/snow for lower elevations. This is still a very fluid situation so there remains high uncertainty regarding the forecast. Hopefully, the impacts and timing of this system come into better focus over the next 12-24 hours.

DISCUSSION

Issued at 130 AM MDT Fri Apr 24 2026

Upper level low continues to spin to the north along the MT/Canada border with a multitude of shortwaves to come through early next week. A pretty flattened bottom of the low for the state Friday into Saturday that will see mainly higher elevation snow during this time with little to no impacts expected (outside of the mountain passes). Light snow in the lower basins east of the Divide continue through Friday morning as the "heavier" bands continue to weaken with its eastward progression. This will be out of the CWA by sunrise to mid morning with any lingering snow contained to the higher elevations for the northern half of the state. Otherwise, winds have weakened behind FROPA with cooler, more seasonable temperatures to be had Friday and into the weekend.

The longwave pattern looks to deepen the aforementioned upper low come Saturday night into Sunday elongating in the process due to increased divergence aloft. This will bring a more southwest upper level flow that will be more favorable to lower elevations east of the Divide outside the upper Wind River Basin blocked more by downslope. This will begin a series of more substantial precipitation amounts to affect much of the CWA, but details are uncertain at this time with timing as well. Regardless, the "cooler" atmosphere will continue to be closer to seasonable for the end of April as the upper level low finally begins a more progressive eastward progression by mid next week. This will allow for upper level ridging to build in from the west by week's end that will bring a dry and warming trend by the following weekend. The uncertainty with the Sunday through Tuesday forecast comes with whether or not the base of the aforementioned trough stays as an open wave or not with the main low circulation remaining to the north. This will allow it to be more progressive and less of an overall impact, albeit still seeing good amounts of moisture to filter through the area from the Pacific Californian Coast. Stay tuned for updated forecasts in the coming days but for now, expect a cooler, more active pattern to continue in some fashion over the next several days.

AVIATION /00Z TAFS THROUGH 00Z SUNDAY/

Issued at 440 PM MDT Fri Apr 24 2026

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

Showers are lingering mainly on higher elevations around KBPI/KPNA/KJAC, and should be moving east during the mid-evening. Expect skies to thin out and lift by 06Z, with VFR conditions continuing through the day Saturday. KRKS will continue with gusty winds approaching 40kts through mid-evening, before quickly decreasing for the overnight hours. Winds at KRKS will increase back to 15 to 20kts around 18Z Saturday.

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

Showers are starting to decrease currently, and will mostly be done by around 03Z. Main issue overnight will be low clouds and fog for KCPR/KRIW/KLND. KCPR/KLND will be IFR/LIFR thresholds below 1000 feet most of the night, with KCPR possibly seeing very light snowfall as well through the night. Added moisture from snowmelt may also bring some sfc fog to these regions as well, especially KLND. Clearing skies late will extend into the day Saturday, with VFR conditions, along with light winds, expected at all sites.

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.