Area Forecast Discussion
Issued by NWS Glasgow, MT
Issued by NWS Glasgow, MT
877 FXUS65 KGGW 251456 AFDGGW Area Forecast Discussion National Weather Service Glasgow MT 856 AM MDT Sat May 25 2024 .DISCUSSION... Fog is lifting or burning off this morning as expected. A glance at tomorrow shows that thunderstorms later in the day may contain gusty winds, according to the Max wind gust ensemble from the HREF. Therefore added a gusty wind element. Rest of forecast seemed to be in good shape. TFJ Previous Discussion... KEY MESSAGES: 1) Scattered showers and general thunderstorms will start in the west late this afternoon and move across northeast montana slowly overnight. 2) Expect a slow warming trend into Wednesday with widespread 80s Tuesday and Wednesday. 3) Any fog early this morning over the Missouri and Milk River valleys or north of them will likely clear out before or around 9AM. WEATHER PATTERN OVERVIEW: With dewpoint depressions near 1 to 2 degrees across the region and rain falling just before or after sundown and night time clearing of skies. Fog will be possible this morning with greatest chance being over the Missouri River Valley and areas north of the missouri and Milk river valleys being most impacted. This fog should clear around 7 to 9 AM. Unsettled pattern will hold with two distinct periods for prolonged showers and thunderstorms. One is this afternoon to Sunday evening, while the other is Wednesday afternoon to Thursday evening. Rain totals appear to vary from a couple hundredths to upwards of a quarter of an inch with a tenth of an inch being the most common output for the first event. The second event is more in flux with synoptic features not quite settling into place yet and therefore a good determination on rain totals can not yet be derived. A ridge will build into the area between these two rain events allowing highs to reach the widespread 80s by Tuesday and Wednesday. CONFIDENCE & DEVIATIONS: Confidence in morning fog seems shaky as model output across the board is failing to place any fog along the Missouri and Milk River Valleys in well known locations like Wolf Point(KOLF) and Poplar(KPO1). Currently having to go off script and hand enter data into the hourlies through about sunup. Confidence holds fairly strong through about Wednesday when the second shortwave arrives and ensemble consistency begins to break apart. Surface wind fields at this time are in flux along with rainfall total grouping being wider over the ensembles. A surface low pressure system may or may not form with the disturbance`s passage with about half the ensembles producing it. GAH/TFJ && .AVIATION... LAST UPDATED: 1500Z FLIGHT CAT: Becoming VFR by 18z. DISCUSSION: Patchy fog is lifting/burning off this morning. A new round of rain showers and isolated thunderstorms is expected to begin impacting the terminals around 22Z and last into the nighttime hours. These showers may not fully clear from northeast Montana until about Sunday evening. SFC WIND: Light and variable this morning through the rest of today and becoming east this evening. GAH/TFJ && .GGW WATCHES/WARNINGS/ADVISORIES... None. && $$ weather.gov/glasgow