Area Forecast Discussion
Issued by NWS Riverton, WY
Issued by NWS Riverton, WY
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500 FXUS65 KRIW 181800 AFDRIW Area Forecast Discussion National Weather Service Riverton WY 1100 AM MST Tue Nov 18 2025 .KEY MESSAGES... - Showers linger over portions of the Cowboy State this morning and look to dissipate by the early afternoon. - Near seasonable temperatures and mostly quiet conditions are expected to persist through the next couple of days. - A few isolated showers cannot be ruled out at times this week mainly over portions of western and southern WY. - Fall-like temperatures and mostly quiet weather look to prevail into the weekend with unsettled weather possibly returning for next week. && .DISCUSSION... Issued at 207 AM MST Tue Nov 18 2025 A soggy start to the week across the Cowboy State as Monday saw periods of showers throughout the day. Isolated to scattered showers will linger through the first half of the day. The best chances (20- 40%) for precipitation this morning remains over western WY. Central parts of the state see lesser chances around 20% with coverage decreasing throughout the morning into the early afternoon. One thing to monitor this morning will be the potential for some areas of patchy fog. Due to the recent precipitation there is a surplus of moisture currently sitting across the state. The best chances (10- 30%) for some fog development looks to be across western valleys such as Jackson Hole and Star Valley. Isolated fog cannot be ruled out east of the Divide in portions of the central basins this morning. Skies remain partly to mostly cloudy which should limit any daytime heating. More seasonable temperatures are forecast today with highs ranging from the 40s west of the Divide and 50s east of the Divide. The remainder of the week looks rather quiet and fall-like. Around seasonable temperatures will persist with highs in the 40s west of the Divide and 50s east of the Divide through the next couple days. An upper level low over the southwestern CONUS may push moisture into the region throughout the week. This could lead to some isolated showers at times with the best chances (10-30%) being over portions of western and southern WY. Overall, things will be mostly uneventful as multiple disturbances will track too far from the area to see any noteworthy impacts here. Models have come into better agreement regarding the aforementioned upper level low currently over the southwestern CONUS. The consensus looks to have this low shift more east than north, leading little to no impacts as a result. The next disturbance that digs south from the PACNW by the second half of the week is starting to look like it may do the same. Models have this low dig well too south of the region by the weekend resulting in little to no impacts for the state. Instead, some weak ridging tries to build in for the weekend, which would lead to seasonable and mostly quiet weather prevailing into the start of next week. While many snow lovers and ski resorts may be quite disappointed by the string of bad luck regarding the lack of snow east and west of the Divide to start the season, there is some hope. Long range models do keep the jet stream active with multiple disturbances moving across the western CONUS throughout next week. So at this time there is still way too much uncertainty to really have a grasp on what we can expect. However, due to the jet stream remaining active and the influx of energy all we need is the right setup and track to possibly see some snow. With that being said those who are wanting some snow should probably start looking for four leaf clovers to maybe increase those chances. && .AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/... Issued at 1059 AM MST Tue Nov 18 2025 MVFR to IFR ceilings are currently noted at KBPI, KPNA, and KJAC late this morning. These conditions should be short-lived, with lifting ceilings expected over the next few hours. However, KJAC could be the exception as a shortwave keeps light showers going in the mountains of western Wyoming. Trends will be monitored closely for the possible extension of MVFR/IFR ceilings longer into the afternoon today. Broken to overcast VFR ceilings are expected to persist at most terminals overnight as additional moisture and clouds spread into the area from the south. KCPR will see a breezy southwest wind through the period, with all other terminals remaining under 10 knots. 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. && $$ DISCUSSION...Dziewaltowski AVIATION...Myers