textproduct: Western and Central Wyoming

KEY MESSAGES

- Unsettled with scattered rain/snow showers across much of the state this afternoon and evening. An isolated thunderstorm cannot be ruled out.

- Unsettled weather continues into the later half of the week with daily chances for showers.

- A weak disturbance may bring a period of rain/snow to portions of central WY Wednesday night into Thursday morning.

- Drier and warmer weather gradually returns to the Cowboy State for the end of the week into the weekend.

UPDATE

Issued at 117 PM MDT Tue Apr 28 2026

Not much to update with the previous forecast remaining on track. Showers are currently bubbling up across much of the forecast area with an isolated thunderstorm possible through the afternoon and evening. Some locations depending on temperatures may see brief snow squalls, which would quickly reduce visibility and create some hazardous driving conditions at times. A few showers may linger past sunset but the majority of precipitation should dissipate before midnight. Another round of showers will be possible over much of the state tomorrow. The focus will be towards Wednesday evening into Thursday morning. Models are showing a brief period of upsloping which would create favorable dynamics for prevailing precipitation across parts of central WY. At this time, temperatures would be flirting with freezing so its possible some locations may see a transition from rain to wet snow overnight Wednesday. Depending on how quickly temperatures can cool and how intense the precipitation is, its possible some locations may see some snow accumulation by Thursday morning. However, there still remains uncertainty and a better idea of what to expect should come into focus in the next 12 or so hours.

DISCUSSION

Issued at 253 AM MDT Tue Apr 28 2026

Unsettled weather looks to continue through the next three days or so. Right now we are having some snow showers and a few snowbands, largely across central Wyoming. This is courtesy of a weak area of low pressure and shortwave passing to the south at this time. Most of these showers should be gone by morning. In addition, with a decent amount of low level moisture in the air, the fog monster has decided to climb out of his lair in a few spots. Today looks similar to yesterday in regards to precipitation, with a scattering of showers around the area, with an emphasis on northern Wyoming. And with the showery nature of the precipitation, pinpointing them is difficult at best. In general, amounts look rather light, with only the mountains having a greater than 1 in 3 chance of a tenth of an inch or more of QPF through midnight. As for snow, no real impacts as the chance of greater than 3 inches in the mountains is less than 1 out of 10 everywhere. And, with lifted indices dropping to minus 1 and a bit of surface CAPE, we could even see a few thunderstorms. The main threat from these would be small hail or graupel given the low wet bulb zero levels. With a bit more sunshine, temperatures will be around 5 to 10 degrees warmer than yesterday, but still below normal.

The next shortwave then drop southward into the area for Wednesday. This wave has a bit more moisture and forcing with it, so the chance of showers this week will likely reach a peak here. However, again with the showery nature of the precipitation, it is difficult to pick an area of focus. As for snow, there is a better chance of accumulation in the mountains. The chance of advisory amounts of snow remains very low. The only locations with a greater than 1 in 4 chance of 6 inches or more are the highest peaks and since are no roads and basically no people, little to no impact.

One last shortwave then moves through on Thursday with another chance of showers and storms. One thing that gives me a bit of concern is a few models are showing a weak 700 millibar low that may bring some local enhancement of the precipitation. These are notoriously fickle even 12 hours out let alone three days so uncertainty is high but the possibility is there. Right now, guidance is favoring central portions of Wyoming, but we will see.

Ridging should finally build across the area on Friday and bring a nice early Spring day with sunshine, light to moderate wind and seasonal temperatures. Uncertainty then increases this weekend as a cold front approaches the area from the north and west. There is lot of disagreement in the timing of the front. For example, the European drops the front Saturday, with other models waiting until Sunday. There has also been a lack of run to run consistency with this feature. So, although we are fairly confident of a front approaching this weekend, details on the timing and placement of precipitation remains highly in doubt.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1128 AM MDT Tue Apr 28 2026

VFR flight conditions are largely expected through 18Z Wednesday at all terminals. However, there could be a few instances (20 to 30 percent chance) of MVFR ceilings at KCPR through 22Z with any showers. Isolated and spotty showers are forecast to develop near KJAC, KCOD, and KLND between 20Z and 21Z. Confidence is around 30 percent in a shower directly impacting these three terminals, so opted for a PROB30 at this time. Instances of MVFR flight conditions cannot be ruled out for a brief period should there be a heavier shower. Mountain obscurations can also be expected around KJAC, KCOD, KLND, and KCPR. There is a 90 percent chance that all other terminals remain dry.

Breezy winds will occur at KRKS, KCPR, KPNA, and KBPI through sunset this evening. Frequent gusts around 20 to 30 kts can be expected with KRKS seeing the higher end of that range. Winds remain 12 kts or less at all other terminals.

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.