Area Forecast Discussion
Issued by NWS Riverton, WY
Issued by NWS Riverton, WY
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825 FXUS65 KRIW 121832 AFDRIW Area Forecast Discussion National Weather Service Riverton WY 1132 AM MST Wed Nov 12 2025 .KEY MESSAGES... - Warmer than average temperatures (5 to 15 degrees) and dry conditions today and tomorrow. - Increasing precipitation chances west of the Divide Friday and into the weekend. - Seasonable temperatures and wetter conditions next week with multiple weather systems. && .UPDATE... Issued at 1130 AM MST Wed Nov 12 2025 No major changes with this update, with mild temperatures and dry conditions today. Clouds continue to increase through the day, and then slowly clear overnight and into Thursday morning. Snow over the western mountains continues to trend down for the Friday/Saturday weather system. Wind ahead of the system (on Friday) picks up, with widespread gusts over 20 mph, with many of the more wind-prone areas (like South Pass to Casper) in the 30 to 45 mph range. && .DISCUSSION... Issued at 1200 AM MST Wed Nov 12 2025 WV imagery continues to show the strong upper level ridging across the western portions of the country with just some high clouds spilling over it across the CWA on IR. This will continue to be the case Wednesday and Thursday with the strong convergence aloft as the main finger of the PFJ remains well north. As such, expect the warming and dry trend to continue both of these days ahead of the next system come Friday and into the weekend. Regardless, expect warmer than average temperatures (5 to 15 degrees), and some breezy winds once again each afternoon. Models indicate a trending down of accumulating snowfall west of the Divide for the western mountains. HREF shows the best chance to be over 2 to 4 inches at this point in time (70-80%), with much less chances for anything over that (20-30%). As such, confidence has continued to drop for any significant weather to occur at this time with any hazards less likely for Friday into Saturday. Mountain passes will still be affected, just not to the extent as once thought earlier in the week. Timing will continue to be the key as well with early Friday morning start times to precipitation to push in from Idaho with much of it being during the daytime. Anything in the lower valleys west of the Divide is more likely to be just rainfall at this point in time as temperatures do not become more seasonable until overnight Friday and into the weekend behind cold frontal passage. The Euro continues to handle the system a bit better longer term as the GFS has, with now indications of the PFJ cutting the main Pacific northwest trough off into a closed low near southern California. The main energy looks to hold off until late Sunday night and into early next week. Even with that said, the system overall itself looks to be more progressive. As such, expect amounts even beyond this to be less than previously forecasted. The overall pattern continues to be active into much of next week as well with the main finger of the PFJ continuing to pump in the Pacific moisture west of the Divide with a series of trough-ridge couplets to propagate through the upper Rockies. && .AVIATION /18Z TAFS THROUGH 18Z THURSDAY/... Issued at 1019 AM MST Wed Nov 12 2025 VFR flight conditions persist the entire TAF period with increasing BKN to OVC mid level clouds. Winds are forecast to remain less than 10kts at most terminals. The exceptions are KCOD and KCPR. At COD, there is a 60% chance in wind gusts between 15-20kts through 23Z/00Z. At KCPR, confidence is high (80%) in wind gusts around 25kts until 23Z. 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. && $$ UPDATE...Wittmann DISCUSSION...Lowe AVIATION...Gerhardt