Area Forecast Discussion
Issued by NWS Billings, MT
Issued by NWS Billings, MT
028 FXUS65 KBYZ 201654 AFDBYZ Area Forecast Discussion...Updated National Weather Service Billings MT 1054 AM MDT Fri Sep 20 2024 .UPDATE... Cold front was pushing S thru NW MT late this morning toward KTFX. There were a few showers and thunderstorms N of the Canadian border in an area of lift from vorticity and frontogenesis. Models bring the front through the forecast area from 21Z-00Z. Deterministic models and CAMS showed QPF along/behind the front as it moves through the area. There will be lift from vorticity and frontogenesis. PWAT`s also forecast to rise ahead of the front. Instability was limited, so not expecting thunder. Placed 20% PoPs along/behind the front from 21Z to 06Z tonight based on model forecasts. Otherwise, rest of forecast was in good shape. Gusty winds around KLVM and KBHK were being handled well, and temps looked fine. Arthur && .DISCUSSION... Today through Saturday night... Deep westerly downslope flow will boost temps above normal again today with highs ranging from mid 70s west to around 80 degrees east. Look for winds 15 to 30 mph in many areas in the afternoon. A trough moving across Canada will then force a cold front down across our area late today into the evening with winds turning to the north. This looks like a mainly dry frontal passage aside from isolated showers over the Beartooths and across east central Montana (northern Custer, Fallon Counties). Surface high pressure will settle over the region for Saturday resulting in quiet and cooler weather conditions. Highs Saturday will be mainly 60-65 with 40s in the high country. A rather autumn-like day. BT Sunday through Friday... Ridging will prevail for most of Sunday, ahead of a quick moving trough and shortwave moving through the PNW. High temperatures will be near normals, in the low 70s, with a negligible chance for precipitation. Models depict the approaching trough moving through the state, Sunday night into Monday morning. There is still high uncertainty on what to expect with this wave as it pertains to moisture and the chance for precipitation. Of the deterministic models, most of them are not depicting much precip with this system, though the ECMWF does, and it shows a low to moderate chance. As a result, the latest NBM forecast shows a 15-40% chance of precipitation (best chance in the west). Cooler temperatures are forecasted for Monday, in the 60s to 70F. After this wave, ensembles generally agree that ridging will rebuild over the Mountain West, Tuesday through Friday. Warm and dry conditions will be felt across the region, with highs in the 70s to low 80s. Ensembles are hinting at another upper trough moving across the PNW, late next week, though it is too soon to determine if this will come to fruition. Matos && .AVIATION... VFR conditions are expected through the TAF period. A cold front sweeps through the region late this afternoon into tonight bringing sct-bkn clouds with bases in the 4kft-7kft range. Isolated rain showers are also possible. Surface high pressure returns by Saturday morning with quiet weather expected the remainder of the TAF period. && .PRELIMINARY POINT TEMP/POPS... Tdy Sat Sun Mon Tue Wed Thu ------------------------------------------------------- BIL 076 043/061 040/072 050/069 046/074 049/081 052/082 2/W 20/U 00/U 12/W 00/U 00/U 00/U LVM 074 034/062 034/074 044/068 040/074 044/082 047/080 0/N 00/U 00/U 23/W 00/U 00/U 01/U HDN 078 041/062 037/072 045/070 043/075 044/083 048/083 2/W 20/U 00/U 02/W 00/U 00/U 00/U MLS 077 045/062 039/072 045/070 045/073 046/081 052/083 2/W 20/U 00/U 01/B 00/U 00/U 00/U 4BQ 080 044/062 038/073 045/069 045/073 046/082 052/084 0/U 20/U 00/U 01/B 00/U 00/U 00/U BHK 079 042/062 035/071 042/069 043/073 044/080 049/083 2/W 20/U 00/U 00/B 00/B 00/U 00/U SHR 081 039/063 035/075 042/068 039/074 041/084 046/084 0/U 20/U 00/U 03/W 10/U 00/U 00/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$ weather.gov/billings