textproduct: Western and Central Wyoming

KEY MESSAGES

- Temperatures east of the Divide will be 12-18F below normal today, in the wake of a cold front Friday night. Extensive cloud cover through Saturday evening will aid in the cooler temperatures.

- Lower elevation rain and mountain snow showers occur between mainly sunrise and noon across northern portions of the forecast area. The best chances (50 to 80 percent) occur over the Bighorn Mountains and Johnson County during this time.

- Conditions improve Sunday and lead into a warming trend starting Monday, with limited to no rain chances.

- Elevated to critical fire weather conditions will be in place starting Monday as well, with Tuesday looking to be the most critical.

DISCUSSION

Issued at 147 AM MDT Sat Jun 13 2026

The cold front reached the Divide early this morning and will cross the Divide after sunrise as it slowly continues southward today. An area of showers continues just north of the state line over southern MT. These showers will reach the Bighorn Basin and northern portions of Johnson County by the predawn hours. Most of the precipitation will occur in Johnson County and the Bighorns, where model trends have increased amounts close 0.50" near Buffalo and Powder River Pass between 12Z and 18Z (6AM and 12PM). This would result in snowfall amounts of 5-6" above 9000ft. There is currently no lightning occurring in these showers and none are expected through the rest of the morning, as conditions are relatively stable with temperatures in the 40s and lower 50s. These showers will dwindle by 18Z, with a 30 to 60% chance continuing over the Absarokas and Bighorns through the rest of the day. An isolated lightning strike could occur over these areas in the afternoon, but confidence is low. The rest of the forecast area will be dry and cool, with temperatures in the 50s to lower 60s east of the Divide and in the 60s and 70s west of the Divide. The progression of the cold front over southern portions will be slowed by northwest winds over southwestern portions of the state. The front will finally reach the Green River Basin after sunset, as the northwest winds weaken. Easterly wind gusts of 25 to 45 mph will occur across southern portions of the CWA behind the front through the night and into Sunday morning.

Seasonal temperatures will be in place across the CWA Sunday with highs in the upper 60s into the 70s. Conditions will be dry, except for very isolated showers possible over central portions throughout the day. Winds will be light as well, with gusts of 20 t0 25 mph occurring over the southern half of Sweetwater County.

A warming trend will begin Monday, with a northwest flow pattern aloft in place. Heights will rise Tuesday within this pattern, leading to high temperatures in the upper 80s to lower 90s in the Wind River and Bighorn Basins and portions of Natrona County. Temperatures will be slightly cooler Wednesday, as a cold front clips northern portions of the state. This looks to be the best chances for any precipitation next week as well, as much of the week looks to stay dry. Fire weather conditions will be elevated to critical through the week as well, with Tuesday looking to be the most critical.

AVIATION /06Z TAFS THROUGH 06Z SUNDAY/

Issued at 1028 PM MDT Fri Jun 12 2026

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

Fairly benign aviation weather west of the Divide during the next 24 hours. Skies remain mostly clear into Saturday evening, while west winds only reach around 10kts for KBPI/KPNA/KJAC, and gust 15 to 20kts for KRKS. After 00Z/14, the front will sweep southward toward KRKS, bringing north winds gusting 25 to 35kts. Lower clouds are not yet expected, and if they do form, they will wait until after 06Z/14.

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

The cold front is moving into far northern WY at this moment, with cigs falling quickly during the next 3 hours at KCOD and KWRL, very close to IFR levels. The low clouds will continue to push southward overnight, reaching KRIW/KLND and KCPR between 12Z and 15Z. As cigs lower, some rain is expected at KCOD through mid-morning. Chances have increased, so made the precip the predominant conditions for those hours. Rain will also shift toward KWRL, but overall period of precip will be very short and lower confidence, so have held to PROB30 group. Cigs fall near MVFR at KLND/KRIW and near IFR at KCPR mid-morning through early afternoon before thinning late afternoon. Lingering moisture will bring a return of some low clouds at KCOD/KRIW/KLND Saturday night, but is currently expected to remain at or above 4000 ft.

RIW WATCHES/WARNINGS/ADVISORIES

None.