


Area Forecast Discussion
Issued by NWS Glasgow, MT
Issued by NWS Glasgow, MT
792 FXUS65 KGGW 132023 AFDGGW Area Forecast Discussion National Weather Service Glasgow MT 223 PM MDT Sun Jul 13 2025 .DISCUSSION... KEY MESSAGES: 1) Gusty northwest winds are possible late Monday with a cold frontal passage. 2) Look for increasing chances for showers and thunderstorms gradually tonight and Monday along the Canadian border and becoming more widespread across NE Montana Monday night. Isolated strong to severe thunderstorms are possible Monday evening. 2) Widespread wet weather and cooler temperatures look to be in place area wide by Tuesday. Total rainfall across the region will range between 0.25" and 0.75" for most locations with isolated higher totals. WEATHER PATTERN OVERVIEW: A frontal boundary looks to keep showers and thunderstorms confined to the Canadian border today and Monday, but as it shifts south as a cold front Monday evening and Monday night expect showers and thunderstorms to spread to the entire region. Winds could become gusty at times during afternoon and evening hours and marginally supportive for a Lake Wind Advisory across Fort Peck Lake. Monday evening, HREF max ensemble wind gust and max updraft helicity lend support for an isolated severe thunderstorm threat. Large hail and damaging winds would be primary concerns with the timing mainly after 4pm. Otherwise showers and thunderstorms will be more widespread Monday night into Tuesday, with heavy rainfall a distinct possibility. In fact, widespread 0.25" to 0.75" of total QPF are expected to be common across NE Montana with isolated 1" totals where heavier thunderstorms occur through Tuesday. Tuesday will also feature far cooler temperatures. An early look at ensembles support a return to near normal temperatures by the end of the week but with active weather continuing at times. FORECAST CONFIDENCE & DEVIATIONS: Confidence is moderate to high that thunderstorm chances will increase across NE Montana Monday into Tuesday with widespread steady rainfall amounts. However, somewhat lower confidence exists on a severe weather potential due to the isolated nature of expected risk. NBM was otherwise largely used for the forecast period which captured expected overall trends well for this cycle. && .AVIATION... LAST UPDATED: 2015Z on July 13, 2025 FLIGHT CAT RANGE: VFR. DISCUSSION: VFR conditions will continue amid high and mid level clouds through tonight. Most showers and thunderstorms will remain north of area terminals. Winds: Look for east winds at 5 to 15 kts tonight, becoming northwest at 5 to 15 kts on Monday afternoon and evening with occasional stronger gusts to 25 kts. && .GGW WATCHES/WARNINGS/ADVISORIES... None. && $$ weather.gov/glasgow