Area Forecast Discussion
Issued by NWS Glasgow, MT
Issued by NWS Glasgow, MT
409 FXUS65 KGGW 181951 AFDGGW Area Forecast Discussion National Weather Service Glasgow MT 151 PM MDT Tue Jun 18 2024 .DISCUSSION... KEY MESSAGES: - Clouds will clear from the south tonight after the showers diminish later today. - Warmer temperatures starting on Wednesday with frequent chances for showers and thunderstorm chances between Wednesday and Saturday, especially Friday afternoon and night. WEATHER PATTERN OVERVIEW: The upper flow will become southwest as the disturbance that brought the rain to the area moves out. This will leave the area somewhat unsettled the remainder of this week. An upper trough to our west splits on Thursday and the northern branch trough moves inland along the Canadian Border starting Thursday night and reaching eastern Montana on Saturday. This will gradually increase the chances for showers and thunderstorms between Thursday night and Saturday. With warmer temperatures, some of these thunderstorms could be severe. An upper ridge on Sunday brings hot and dry weather with highs near 90 then a slight cooldown occurs next week. FORECAST CONFIDENCE and DEVIATIONS: There is low confidence on patchy fog occurring tonight where skies clear, mainly in valley locations. From Wednesday onward, confidence is high on a gradual warming trend. Confidence is low on precipitation chances Wednesday and Thursday. Confidence increases to moderate of precipitation chances between Thursday night and Saturday. TFJ && .AVIATION... LAST UPDATE: 2030Z FLIGHT CAT RANGE: IFR (KGDV) till 00z/ MVFR (KSDY) - both improve to VFR Wed morning (between 12z and 16z). Otherwise, VFR. DISCUSSION: An area of rain NW of KSDY to KGDV will gradually diminish. Isolated rainshowers west of this area is expected to diminish by this evening. Low clouds may linger at KGDV and KSDY into Wednesday morning. Widespread fog is not expected Wednesday morning but it may be in isolated locations. WIND: Light West then SW winds tonight (less than 10 kts) then increase from the South Wednesday. * We will continue at add "AMD NOT SKED" to the KSDY TAF till it is available online. TFJ && .GGW WATCHES/WARNINGS/ADVISORIES... None. && $$ weather.gov/glasgow