052 FXUS65 KTFX 060207 AFDTFX Area Forecast Discussion National Weather Service Great Falls MT 807 PM MDT Sat Oct 5 2019 .UPDATE... Main updates to the overnight forecast were to sky and temperatures. Skies have cleared out a bit quicker than previously expected, so have reflected that in the forecast. Because of this, have lowered lows about 4 to 8 degrees in the Southwest Montana valleys, especially in the mountain valleys, where lows could reach the teens. Coulston && .SYNOPSIS... Scattered showers with breezy west winds will diminish through this evening across the region. Mostly clear skies and warmer temperatures are then expected for Sunday. Monday will be even warmer, but this will come with strong westerly winds. A strong cold front will then bring a change to much colder temperatures with accumulating snowfall for Tuesday through Wednesday, as breezy winds shift more so out of the north. && .AVIATION... Updated 550 PM MDT Sat Oct 5 2019 (06/00Z TAF Issuance) VFR conditions are expected for most of this period; however, a disturbance in the northwest flow aloft will continue mountain top obscuring rain and snow showers with periods of MVFR conditions through 03Z south of a KGTF-KLWT line. Otherwise, skies will become partly cloudy through 06Z as high pressure starts building into the area. However, the northwest flow aloft will be just off the surface over North Central Montana (KCTB KHVR KGTF KLWT), so low level wind shear is possible there until the winds start to mix down to the surface after 15Z. Coulston && .PREV DISCUSSION... /ISSUED 550 PM MDT Sat Oct 5 2019/ Tonight through Monday night... Upper level disturbance will continue to push across the region throughout the evening. So far shower activity has been pretty limited. Still have chances for rain with snow above 5000 feet throughout the evening hours mainly across western, central, and southern portions. An isolated thunderstorms is still possible, although abundant cloud cover has brought limited instability to the region. Showers then end tonight with clearing skies into Sunday morning. The remainder of Sunday will see dry and warming temperatures under dry northwest flow and weak ridging. Look for highs to overall warm into the low to mid 50s for most lower elevation areas. Breezy winds may also linger in west northwest flow aloft. Flow flattens and become more westerly for Sunday night into Monday. The result could be some widespread breezy to perhaps windy conditions especially across the central and northern plains. Winds really looks to get going more in the evening through the overnight hours, with some 50+ knot winds at 700 mb. Uncertainty remains if these winds can fully mix down Monday evening into Tuesday morning. This will need to be continued to monitored for any potential wind highlights. The downsloping winds will provide for mainly dry conditons for Monday and warming temperatures. Most areas should see high temps get into the 60s, with Monday morning lows in the 30s and Monday night into Tuesday morning lows in the 30s and 40s. Late Monday night into Tuesday morning the flow picks up some moisture ahead of an approaching trough. This could bring snow above 7000 feet across the Rocky Mountain Front, and possibly rain into the adjacent high plains. Anglin Tuesday through Saturday... The developing upper level trough over western Canada deepens into the Pacific Northwest by Tuesday morning then is expected to sweep across the Northern Rockies Tuesday through Wednesday. Medium range diagnostic models and ensembles remain in very good agreement for mid to late week and bring an associated surface cold front southward from Canada by Tuesday afternoon. Temperatures behind the front will likely drop 20 to 30 degrees with widespread accumulating snows anticipated from Tuesday through Wednesday night. Latest National Blend of Models (NBM) QPF amounts indicate that this storm system could require winter storm warnings in the mountains with advisories probably also being required over the plains and in the valleys. The effects of this system could linger through Thursday with at least cold temperatures across the region and drying conditions. The upper trough and associated storm system will move into the Great Lakes region on Friday, leaving Montana beneath shortwave ridging for warmer temperatures and mostly dry conditions Friday and Saturday. mpj && .PRELIMINARY POINT TEMPS/POPS... GTF 36 55 38 64 / 10 0 0 0 CTB 34 50 35 58 / 0 0 0 0 HLN 34 58 34 65 / 0 0 0 0 BZN 22 55 28 64 / 20 0 0 0 WEY 15 45 17 52 / 40 0 0 0 DLN 25 52 28 59 / 10 0 0 0 HVR 36 56 35 67 / 0 0 0 0 LWT 34 54 35 65 / 10 0 0 0 && .TFX WATCHES/WARNINGS/ADVISORIES... None. && $$ http://www.weather.gov/greatfalls