textproduct: Western and Central Wyoming

KEY MESSAGES

- Some isolated rain showers have dissipated and pushed east this morning with no impacts expected.

- Gusty west winds and a bit cooler temperatures this afternoon as a cold front approaches from the north, turning winds northerly behind it remaining elevated for a couple hours post FROPA.

- More seasonable temperatures over the weekend with breezy winds through the areas of the wind corridor along with some scattered showers further south in Sweetwater County Saturday. - A stronger and mainly dry cold front pushes through Sunday that will bring cooler air to start the new work week Monday, freezing morning temperatures west of the Divide and low 40s to the east.

DISCUSSION

Issued at 158 AM MDT Fri Sep 11 2026

Moisture has finally arrived over the Cowboy State, ending this prolonged streak of critical fire weather conditions. Partly to mostly cloudy skies continue over the state this morning, scattering out by midday day. Isolated showers to the west of PIH and SLC will continue to track eastward this morning and move over far western portions of the forecast area around 10Z. Virga is likely from these showers, but amounts around 0.05" will be possible over the Tetons/Gros Ventres and toward Union/Togwotee Pass. These showers may cross the Divide and move over the Upper Green River Basin, after sunrise this morning, but will likely stay as virga. These showers are expected to end by 18Z, with dry conditions expected through the rest of the day. There is a 10% chance for virga showers over areas east of the Divide late in the afternoon as a cold front drops southward.

Widespread gusty winds will be the main concern again today, with west wind gusts of 25 to 35 mph occurring across the CWA this afternoon. The exception will be portions of the Bighorn Basin and the northern half of Johnson County. Northwest wind gusts up to 30 mph will occur in these areas as a cold front progresses southward through the afternoon. The front will pass through the Bighorn Basin and Johnson County by 00Z Saturday (6pm), quickly reaching the Casper area and Riverton between 01Z and 03Z, eventually becoming stationary along the Divide by 06Z. Temperatures will much cooler today, especially east of the Divide, running about 5 to 10 degrees cooler. This will apply to far northern portions, due to the proximity of the front.

Models have become aligned with the much talked about storm system for this weekend, with not much change from yesterday with the forecast track. The storm system is still forecasted to drop southward along the West Coast tonight into Saturday. The aforementioned cold front will gradually retreat northward Saturday afternoon, due to an increase in southwesterly winds. The front looks to get pushed into the Bighorn Basin and further north into Sheridan County through Saturday afternoon. Apart from isolated showers and thunderstorms over eastern portions of Sweetwater County Saturday afternoon, conditions are expected to remain dry. Precipitation chances continue to be pushed northward as the storm stays further north in MT. Little to no precipitation is now expected from this storm. The associated cold front will push through the Cowboy State Sunday night, clearing the forecast area by 12Z Monday. Sub-freezing temperatures will return to western portions Sunday night/Monday morning, with readings in the upper 30s to lower 40s elsewhere. Dry and cooler conditions will be in place Monday, with highs in the 60s to near 70 degrees across the area. Conditions will remain dry with seasonal temperatures Tuesday. A storm system may impact the region Wednesday, but confidence is low at this point as colder, Canadian airmasses begin to drop southward.

AVIATION /12Z TAFS THROUGH 12Z SATURDAY/

Issued at 500 AM MDT Fri Sep 11 2026

Light showers are moving over western WY this morning and will end by 14Z. The PROB30 group at KJAC remains in the forecast with conditions at VFR. Mountaintop obscurations will continue over the western mountains through 18Z. Otherwise, wind will increase at most terminals after 15Z ahead of a cold front that will push into northern Wyoming after 21Z. This will lead to a wind shift at KCOD, KCPR, KRIW, and KWRL between 23Z and 02Z. There is a 10 to 20% chance for MVFR to IFR ceilings behind the cold front at KCOD and KCPR after 03Z.

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

RIW WATCHES/WARNINGS/ADVISORIES

None.