Area Forecast Discussion
Issued by NWS Glasgow, MT
Issued by NWS Glasgow, MT
111 FXUS65 KGGW 132130 AFDGGW Area Forecast Discussion National Weather Service Glasgow MT 330 PM MDT Fri Sep 13 2024 .DISCUSSION... KEY MESSAGES: 1) A Lake Wind Advisory remains in effect for Fort Peck Lake until 6PM this evening. 2) Dry and warm weather are expected to unfold this weekend. 3) Thunderstorms look to return Monday followed by cooler and wetter weather through the middle of next week. WEATHER PATTERN OVERVIEW: Gusty winds will ease this evening with the Lake Wind Advisory set to expire for Fort Peck Lake by 6pm. Warm and dry weather will unfold this weekend over NE Montana ahead of the next upper level trough. The Pacific trough will deepen across the west with divergent upper flow over the region by Monday. Look for around 1000 J/KG CAPE with 20-30 kts of shear and precipitable water values around an inch over NE Montana according to forecast soundings. Modest instability and a little bit of shear and ample deep moisture should support the chance for multicellcular thunderstorms in the afternoon and evening, with an isolated stronger storm possible. The trough will shift east on Tuesday and Wednesday lending to cool and wet weather over the region. Right now the ensembles favor the wettest conditions over the western zones with NBM 48 hour probability of 1 inch of rain around 40 percent across the Little Rockies through the middle of the week. FORECAST CONFIDENCE & DEVIATIONS: High confidence exists on warm and dry weather for the weekend. Medium confidence exists on thunderstorms Monday given the modest setup. Lower confidence currently exists for the middle of the week given uncertainties in timing and placement of the heaviest rainfall over the region, though general consensus is shaping up to support higher QPF amounts in the west and lesser amounts to the east. && .AVIATION... UPDATED: 2130Z Look for a return to VFR as skies clear tonight. Gusty winds will ease with light south to southwest winds tonight and Saturday. && .GGW WATCHES/WARNINGS/ADVISORIES... Lake Wind Advisory until 6 PM MDT this evening for Central and Southeast Phillips-Central and Southern Valley-Garfield-McCone- Petroleum. && $$ weather.gov/glasgow