FXUS65 KGGW 100916 AFDGGW Area Forecast Discussion National Weather Service Glasgow MT 316 AM MDT Fri May 10 2024 .DISCUSSION... KEY MESSAGES: - Warmer temperatures that will be above normal are expected today through Monday. Either Saturday or Monday will be the warmest days with highs between 75 and 80 in most areas. - There will be frequent chances for showers and thunderstorms beginning Saturday night and continuing for the next several days. WEATHER PATTERN OVERVIEW: An upper level ridge along with surface high pressure will be over the area with mostly clear skies and warmer temperatures. While the ridge moves south and weakens somewhat on Saturday, surface high pressure remains over the area with between 75 and 80 in most areas. A shortwave trough on NW flow aloft Saturday night and Sunday will bring a chance of showers and slightly cooler temperatures on Sunday. Temperatures rebound on Monday ahead of a stronger shortwave trough, with a cold front that will move through the forecast area Monday afternoon and night. Models and ensembles are pointing towards enough instability for a few thunderstorms with this system. NBM has a 10-30 percent probability of a thunderstorm Monday afternoon and night at this point and a 30 to 50 percent chance of measurable precipitation. Temperatures are expected to be near normal Tuesday and beyond. Models and ensembles have upper trough lingering over the area with frequent chances for showers and thunderstorms. CONFIDENCE AND POTENTIAL DEVIATIONS FROM BASE FORECAST: High confidence exists on above average temperatures today through Monday. However, the current NBM highs for this weekend are at the lower end of the NBM possibilities (10-25%), so there is a good chance that the NBM is underforecasting the highs today through Monday. However, not confident enough to raise highs above NBM for now. Low confidence on timing of any showers and thunderstorms Sunday and beyond. Expect, highly variable precipitation amounts next week. && .AVIATION... LAST UPDATED: 0900Z FLIGHT CONDITIONS: VFR DISCUSSION: High pressure and upper level ridge will bring mostly clear skies today and tonight. May see a few mid and high clouds at times. WINDS: Northwest at 5 to 15 kts today, becoming southwest at 5 to 10 kts this evening. && .GGW WATCHES/WARNINGS/ADVISORIES... None. && $$ weather.gov/glasgow