Area Forecast Discussion
Issued by NWS Riverton, WY
Issued by NWS Riverton, WY
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296 FXUS65 KRIW 090705 AFDRIW Area Forecast Discussion National Weather Service Riverton WY 1205 AM MST Sun Nov 9 2025 .KEY MESSAGES... - Minimal chances (<10% chance) for fog near rivers and valley bottoms overnight giving way to seasonable temperatures and a pleasant Sunday. - Warming and dry trend Monday through Thursday with temperatures 10 to 15 degrees above average and breezy winds winds expected in the afternoon hours. - Increasing precipitation chances come Friday and into the weekend. && .DISCUSSION... Issued at 1205 AM MST Sun Nov 9 2025 WV/IR imagery shows mainly cloudless skies across the CWA with ridging evident to the west. This upper level ridge will continue to build in Sunday and into the early part of the work week with increased convergence aloft. With surface high pressure and light winds to go along with the clear skies, there is a low (<10%) chance for patchy fog across some of the areas in Jackson Hole and northern Bighorn Basin/Johnson County. With such a dry airmass, confidence low at this point but there is a hint with the short term model data to occur by sunrise Sunday morning. Otherwise, expect a pleasant Sunday to be had with seasonable temperatures and relatively light winds. Warming and dry trend continues into the new work week with the aforementioned upper level ridge/surface high pressure set in place through mid week. Temperatures 10 to 15 degrees above average expected with breezy winds as well due to the stronger daytime heating and mixing element. This ridge will start to breakdown into Thursday and push east Friday. This will give way to an upper level low currently in the GOA to push near the Pacific northwest coast opening back up the westerly, moisture rich flow for points west of the Divide. Precipitation chances increase as a result for Friday and especially into the weekend. Details not concrete at this time with timing and amounts, but western mountain snow and valley rain probable not expecting it to push east of the Divide at this point in time. Stay tuned for updated forecasts in the coming days. && .AVIATION /06Z TAFS THROUGH 06Z MONDAY/... Issued at 950 PM MST Sat Nov 8 2025 VFR conditions prevail over the next 24 hours. Skies will be clear overnight with very light winds, generally under 6 kt. There is a small chance (10%) for patchy fog near valley bottoms; however, a very dry air mass and lack of recent surface moisture for most areas will mitigate this weather concern. JAC did see precipitation yesterday, so of all terminals in western and central Wyoming, perhaps JAC has the highest chance, but it`s still a low probability threat. Light winds and clear skies continue during the day Sunday. && .RIW WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Lowe AVIATION...VandenBoogart