textproduct: Western and Central Wyoming

KEY MESSAGES

- Unsettled weather continues Wednesday but isolated in nature (10-20% coverage). Temperatures and wind similar to Tuesday.

- A weak disturbance will bring rain/snow Wednesday night into Thursday morning, increased confidence (60-70%) on an inch or two snow accumulation for the Lander Foothills and a couple tenths for the rest of the Wind River Basin.

- Mainly dry and a warming trend into the end of the week and into the weekend.

DISCUSSION

Issued at 200 AM MDT Wed Apr 29 2026

IR currently depicts ample clouds pushing in from the northwest down the upper level ridge to the west and weak troughing over the northern Rockies. WV shows the PFJ dipping around these features with a modest 90-100kt jet at the base of this positively tilted shortwave with its slow eastward progression. Weak diffluence aloft is giving way to a few scattered showers ongoing over the eastern Bighorn Basin and Bighorns themselves, but weakening as the early Wednesday morning progresses. Through the day Wednesday, some isolated shower activity for the northern half of the CWA but not expected much with low confidence on any impacts to be had during daylight hours. Similar temperatures and winds as it was Tuesday.

Models are more aligned with each other of the shortwave to deepen after sunset and into Thursday morning elongating further southwest than what previous models have shown. As such, shower activity Wednesday night looks to be more active across the southern Bighorn Basin and much of the Wind River Basin. CAMs show a weak meso low to develop at the base of the trough that will be enhance for upslope along the northern Owl Creeks and Lander Foothills/Eastern slopes of the Winds. With the colder temperatures overnight, any liquid precipitation will turn to snow after midnight through the early to mid Thursday morning hours. 1 to 2 inches likely for the Lander Foothills (60-70%) with a few outliers of 3 to 4 inches possible (20-30%) dependent on how fast the aforementioned shortwave lifts out to the northeast. When this occurs, precipitation will diminish by mid Thursday morning. A light accumulation of an inch of so for the upslope of the Owl Creeks, and at least a dusting to a couple tenths possible (40-50%) for the other parts of the Wind River Basin to include Riverton itself. Otherwise, expect improving conditions quickly through the remainder of Thursday morning and especially into the afternoon and evening hours. Temperatures about the same Thursday as well but upper level ridging expected to build in overnight into Friday and the weekend.

As the ridge builds, ample convergence aloft will help aid in dry conditions and a warming trend through early next week as well. Temperatures during the afternoon back into the 70s east of the Divide and 60s to the west starting over the weekend, perfect for a trip to the parks and wildlife viewing. The next system to keep an eye on will be by Tuesday/Wednesday next week as the EC keeps trending towards a closed upper level low coming up from the desert Southwest combining with the PFJ dipping further south across the upper Rockies once again. How this comes together is up in the air but this will tend to evolve into a quicker moving open wave that will have minor impacts at best going forward further into the long term forecast. Stay tuned for updates in the coming days as the weather quiets down for the end of the work week and especially over the weekend.

AVIATION /06Z TAFS THROUGH 06Z THURSDAY/

Issued at 1106 PM MDT Tue Apr 28 2026

VFR conditions prevail tonight through Wednesday morning. A few isolated rain showers will persist tonight into Wednesday morning. Scattered rain showers and isolated thunderstorms will develop again Wednesday afternoon. Most convective showers will dissipate after sunset. An area of rain will develop in central Wyoming Wednesday evening, which will impact KLND and KRIW. Conditions will drop to MVFR at these terminals, especially as the rain mixes with snow late Wednesday evening into Wednesday night. Included MVFR VIS at KJAC Wednesday afternoon as heavier showers may reduce VIS. Terminals with the best chance of thunderstorms and PROB30s in the TAFs are KCOD, KCPR, KJAC, KLND, and KRIW. Added PROB30s for rain showers at KBPI and KPNA.

There will be a modest increase in wind Wednesday afternoon averaging 8-13 knots across the area. Some gusts are possible (30%) at KCPR and KRKS. Wind gusts up to 25 knots are possible with the strongest showers and storms Wednesday afternoon into Wednesday evening. Mountain obscuration will occur at times, mainly with convection Wednesday afternoon.

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.