Area Forecast Discussion
Issued by NWS Glasgow, MT
Issued by NWS Glasgow, MT
346 FXUS65 KGGW 042306 AFDGGW Area Forecast Discussion National Weather Service Glasgow MT 506 PM MDT Fri Oct 4 2024 .DISCUSSION... KEY MESSAGES: ++ High Wind Warning start time has been adjusted to start at 9 PM MDT tonight to account for the enhanced 60mph+ likely over the Little Rockies before midnight. ++ - High Wind Warning issued as strong but dry cold front brings high W-NW winds. A few isolated rain showers are possible but only trace amounts of rain expected. - Marginal fire weather concerns may return late this afternoon and into Saturday with gusty winds and low relative humidity. - Seasonal temperatures this weekend give way to above normal temperatures next week. No precipitation expected. WEATHER PATTERN OVERVIEW: Fast moving ridge moves through the region today elevating temperatures 10-15 degrees above yesterday`s maximum readings. By tonight a strong but dry cold front moves through bringing strong W-NW winds of 30-40 mph with gusts up to 60 mph possible. A few isolated light rain showers are possible but only trace amounts possible with any showers that develop. The winds remain elevated through Saturday with a temperature drop of 10 to 20 degrees which will bring maximum temps closer to seasonal averages. This will help recover humidity values but with the elevated winds, fire weather conditions will need to be monitored by the next shifts. At this time have chosen not to issue any Fire Products. By Monday the stubborn Southwestern ridge that refuses to leave the Four Corners region will flex its muscles north again to bring continued dry weather and temperatures well above early October averages through all of next week. By the weekend there is a possibility the next West Coast trough may break down the ridge and cause a pattern change but models diverge widely on this so confidence is low and will have to be monitored as the week progresses. FORECAST CONFIDENCE & DEVIATIONS: ++ Additional deviations for the afternoon package remain in line with the reasoning discussed below; blended in HREF member guidance, as among them, the probabilities of exceeding 60 mph remain especially high (>90% near the Little Rockies and the Missouri River Breaks), which is higher than the NBM Max values which top out only 55-60 mph for forecasts tonight in the aforementioned region. ++ High confidence in strong winds and warm temperatures today as well as a cooldown for Saturday. Blended official with NBM 90 for wind values. NBM has been grossly under forecasting high temperatures with these last few prefrontal warm days so went ahead and went with NBM90 on the temperatures although the spread between NBM10 and NBM90 is pretty small with today`s max. Confidence remains high to medium for next weeks dry spell and above average temperatures. Confidence is low on possible pattern change next weekend. -Bernhart/Enriquez && .AVIATION... LAST UPDATED: 2200Z FLIGHT CATEGORY RANGE: VFR LLWS: Low level wind shear is likely tonight from 02-08Z with the frontal passage. Only about 2 to 3 hours total for any terminal with or just ahead of initial passage. DISCUSSION: Dry conditions this afternoon. Strong cold front moves through tonight with a few isolated showers and little to no rain accumulation. Winds pick up considerably with frontal passage and stay elevated through Saturday. WINDS: S-SE at 15 kts or less this afternoon through the early Evening. Between 04-07Z veering to W-NW at 20-35kts with gusts to 50-55kts through Saturday. Calming to 10 kts or less late Saturday evening. -Enriquez/GAH && .GGW WATCHES/WARNINGS/ADVISORIES... High Wind Warning from 9 PM this evening to 9 PM MDT Saturday for Central and Southeast Phillips-Central and Southern Valley- Daniels-Dawson-Eastern Roosevelt-Garfield-McCone-Northern Phillips-Northern Valley-Petroleum-Prairie-Richland-Sheridan- Southwest Phillips-Western Roosevelt-Wibaux. && $$ weather.gov/glasgow