Area Forecast Discussion
Issued by NWS Glasgow, MT
Issued by NWS Glasgow, MT
054 FXUS65 KGGW 080827 AFDGGW Area Forecast Discussion National Weather Service Glasgow MT 227 AM MDT Sat Jun 8 2024 .DISCUSSION... KEY MESSAGES: - A stalled low pressure system over Saskatchewan will dictate our sensible weather in Northeast Montana now through Sunday. Then, a decent chance of rain showers will arrive early on Monday. - Below normal temperatures are expected through this weekend. - Weak waves in the NW flow aloft to the south of the upper low could bring some isolated showers to the NE half of the area today. - A general warming trend to above-normal temperatures are expected through the remainder of the forecast period. WEATHER PATTERN OVERVIEW: The stalled low pressure center of circulation is apparent in the satellite imagery over central Saskatchewan and its associated low pressure trough axis is spread from northwest to southeast. We are located southwest of that axis. The general NBM forecast trend is heading toward a cooler solution through Sunday afternoon, with hi-res models showing chances for sneaky isolated rain showers here and there. With some radar echoes over Blaine and Phillips Counties at 08Z, and weak waves in the NW flow aloft today ahead of a cold front this evening, will mention isolated showers in the NE half of the forecast area today. Tonight and Sunday will be mainly dry and cool with surface high pressure over the region. Once the stalled trough finally moves east of our region, the flow aloft quickly turns more from the southwest and a more progressive low pressure trough from the Rocky Mountains brings better chances for accumulating rain showers along with isolated thunderstorms, especially from late Sunday night through Monday for our central and eastern zones. There is a 50 percent probability of a quarter inch of rain and a 30 percent probability of a half inch rain for most of NE Montana late Sunday night through Monday at this time. Tuesday onward: Northeast Montana will be on the northern fringes of upper-level ridge influence as models come back into alignment for the region. This results in a general warming trend to above normal high temperatures by mid week. Waves on the periphery of the ridge could bring low chances for showers at times. FORECAST CONFIDENCE and DEVIATIONS: Even though NBM ensembles have recently struggle to resolve this Saskatchewan low pressure trough, slow improvements are showing trends toward lower than average temperatures for today, Sunday and Monday. A ridge of high pressure ahead (east) of the stalled trough is forcing the cold pool to backslide south and west into Montana today where it bumps up against the newly developing ridge over the western half of the CONUS. Forecast confidence is increasing on the chances for rain Sunday night and Monday now that there is better model agreement. For today, I was more generous than the NBM with the isolated showers. && .AVIATION... LAST UPDATE: 0830Z FLIGHT CAT RANGE: VFR DISCUSSION: Mid-level clouds will be over the area today with isolated showers possible. A few showers may generate gusty and erratic winds in their respective vicinity. A cold front this evening bring a break in the clouds and more mid level clouds will move in late tonight. WIND: Becoming light and variable early this morning becoming NW 5 to 10 knots by late morning. Winds will become north 5 to 15 knots this evening and NNE late tonight. Gusty and erratic winds may occur in the vicinity of rain showers. && .GGW WATCHES/WARNINGS/ADVISORIES... None. && $$ weather.gov/glasgow