643 FXUS65 KBYZ 281917 AFDBYZ Area Forecast Discussion National Weather Service Billings MT 117 PM MDT Sun Sep 28 2025 .KEY MESSAGES... - Much above average temperatures through Thursday. - 20-40% precipitation chances Tuesday across the lower elevations. Less than 0.10 inches expected. - Pattern change expected Friday into the weekend with a change to cooler and wetter conditions. - High elevation (>8,000 ft) snow Thursday night through the weekend. && .DISCUSSION... Today through Sunday... There is high confidence in the forecast through Thursday. Above average upper level heights will bring temperatures 10-20 degrees above normal in the 80s F for most. Southwest flow and sufficient moisture will bring 20-40% chances for precipitation for the Absaroka/Beartooth mountains Monday through Wednesday. Tuesday will see these chances (20-40%) spread to lower elevations. The chance for greater than 0.1 inches of precipitation for the lower elevations remains low (<10%). Significant uncertainty enters the forecast starting Thursday as an upper level low from the Pacific northwest starts to move inland. A change to near to below average temperatures has higher confidence while precipitation remains lower confidence. There is disagreement as to how this pattern change will unfold. Some ensemble clusters indicate a cutoff low forming while others indicate a broad trough dropping into the region. A good analogy for this is the differences seen in the deterministic model runs of the GFS and ECMWF. The GFS indicates a cutoff low pattern bringing a Colorado Low over the central and northern plains. This results in precipitation chances over the region Saturday. The ECMWF indicates the broad troughing scenario waiting until Sunday/Monday to create a cutoff low. This scenario would lead to precipitation chances for Monday. The NBM is currently showing 20-40% precipitation chances for the lower elevations Thursday evening through Monday. This is likely due to there being one precipitation event in this timeframe and models can't agree on when. The NBM is giving the region a 20-40% chance of getting greater than 0.5 inches of precipitation over the weekend. Temperatures in the 60s and low 70s F Friday are expected to continue to decrease through the weekend with 50s and low 60s F by Sunday. Starting Thursday night, 700 mb heights are expected to drop to near 0 C. This combined with precipitation chances is expected to bring the first widespread snowfall to the Absaroka/Beartooth mountains. At this time snow levels are expected to be around 8,000-9,000 ft. The NBM is giving a 30-50% chance of getting greater than 6 inches of snowfall over the weekend. Torgerson .AVIATION... Slant range visibility will be reduced at times due to regional wildfire smoke, otherwise VFR will prevail over the next 24 hours under strong high pressure aloft. Isolated light showers and weak t-storms are expected over the Beartooth-Absaroka and Bighorn Mountains late this afternoon and evening. On Monday, look for scattered showers and a few t-storms over the mountains and foothills in the afternoon/evening. Erratic wind gusts are possible near any storms (KLVM & KSHR could be impacted). JKL && .PRELIMINARY POINT TEMP/POPS... Mon Tue Wed Thu Fri Sat Sun ----------------------------------------------------------- BIL 053/083 056/084 055/080 053/080 051/068 046/062 043/060 00/U 01/B 20/U 00/U 23/W 33/W 33/W LVM 050/081 049/077 044/075 045/075 043/064 037/057 033/055 11/U 12/W 21/B 12/W 44/W 44/W 33/W HDN 050/085 052/086 052/080 048/083 049/070 043/065 040/061 00/U 00/B 40/U 00/U 32/W 42/W 32/W MLS 053/087 055/088 056/083 052/084 052/074 047/066 042/063 00/U 00/U 20/U 00/U 21/B 32/W 32/W 4BQ 055/086 058/086 056/080 053/083 053/073 046/065 042/061 00/U 00/U 20/U 00/U 11/B 32/W 32/W BHK 051/086 055/088 052/080 050/083 050/074 044/067 040/060 00/U 00/U 10/U 00/U 11/B 31/B 22/W SHR 050/083 049/083 048/078 046/082 046/070 039/064 035/060 11/U 01/B 30/U 00/U 13/W 43/W 33/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$ weather.gov/billings