FXUS65 KTFX 050445 AFDTFX Area Forecast Discussion National Weather Service Great Falls MT 1045 PM MDT Sat Apr 4 2026 Aviation Section Updated. .KEY MESSAGES... - It will be mostly dry and warm through Monday. - It will be windy on Tuesday across North-central, Central, and Southwestern Montana. - Mountain snowfall will return for Wednesday and Thursday with cooler temperatures. && .DISCUSSION... /Issued 509 PM MDT Sat Apr 4 2026/ - Meteorological Overview: This afternoon there is an upper-level ridge over North-central, Central, and Southwestern Montana. This afternoon a weak upper-level shortwave associated with a surface cold front will move south from Canada through North-central Montana. This will bring isolated light rain showers to portions of the Hi-Line this afternoon and evening. Due to the upper-level ridge it will be warm across North-central, Central, and Southwestern Montana this afternoon. Tonight in areas that clear and have light winds across North-central Montana fog has the potential to form. See the Forecast Confidence & Scenarios section for details. On Sunday the upper-level ridge remains over North-central, Central, and Southwestern Montana. Due to the surface cold front that moved across North-central Montana on Saturday, on Sunday it will be a few degrees cooler than today with the coldest temperatures along the Hi-Line where below seasonal average temperatures are expected. On Sunday there will be isolated light rain showers across the Hi-Line. On Monday the upper-level ridge remains over North-central, Central, and Southwestern Montana. This will bring warm temperatures with dry weather to the area on Monday. On Tuesday an upper-level low associated with a surface cold front tracks along the Canadian/Montana Border. This will briefly bring a strong surface pressure gradient to North-central Montana. Low-level and mid-level winds increase during the day Tuesday. This will lead to windy condtions across North-central, Central, and Southwestern Montana on Tuesday. See the Forecast Confidence & Scenarios section for more details on the winds. The cold front/upper-level low will bring primarily mountain precipitation Tuesday afternoon and evening. On Wednesday there will be an upper-level trough over North- central, Central, and Southwestern Montana. On Wednesday due to the cold frontal passage and upper-level trough it will colder across the area with light mountain snow. On Thursday there will be upper- level zonal flow with a brief upper-level shortwave over North- central, Central, and Southwestern Montana. This will bring another day with cool temperatures and light mountain snowfall. On Friday there will be upper-level zonal flow over North-central, Central, and Southwestern Montana. This will allow temperatures to warm up slightly with mostly dry weather. -IG - Forecast Confidence & Scenarios: From Great Falls up to Cut Bank there is a 10 - 40% chance for fog to form tonight. Along the Rocky Mountain Front there is greater than a 70% chance for fog to form tonight. The biggest uncertainty is that winds in some of those areas might not decrease enough to allow fog to from. On Tuesday there will be a strong pressure gradient for a few hours across North-central Montana and winds aloft will increase. On Tuesday the strongest winds will occur, in the areas where winds at low and mid levels peak in the mid to late afternoon. Another area of uncertainty is that cold air from Canada could move in faster than currently the models are projecting and undercut the strong winds along the Hi-Line. There is also a lower potential for a brief period of strong winds in Southwestern Montana Tuesday afternoon. On Tuesday there is greater than a 50% chance for wind gusts of 55 mph or greater across the lower-elevations of Cascade and Judith Basin Counties. Across the Rocky Mountain Front down to Macdonald Pass and the plains west of I-15 there is greater than an 85% chance for wind gusts in excess of 55 mph. Along the Rocky Mountain Front there is greater than a 80% chance for wind gusts in excess of 75 mph on Tuesday. As a result in these areas on Tuesday a High Wind Watch was issued. Across portions of Central and Southwestern Montana there is greater than a 50% chance for wind gusts of 55 mph or greater. There was low confidence in there being strong wind gusts in these areas for more than an hour or two. Future shifts will continue to monitor the need to expand the current watch to other areas. The areas that are currently in the watch are the areas where there is the highest confidence in receiving impactful wind gusts and or sustained winds on Tuesday. -IG && .AVIATION... 05/06Z TAF Period Initial concern will be for a wind shift to a more northerly direction over much of the plains through the remainder of the night. Some low clouds look to accompany this wind shift, though confidence is low in just how far south these low clouds make it through the day Sunday. A few showers look to develop across the Hi- Line Sunday, though are low probability to occur at any given location. -AM && .PRELIMINARY POINT TEMPS/POPS... GTF 28 49 30 57 / 10 10 10 0 CTB 26 41 26 53 / 10 30 10 0 HLN 32 60 34 62 / 0 0 0 10 BZN 29 63 32 62 / 0 0 0 10 WYS 20 56 24 59 / 0 0 0 0 DLN 29 64 34 66 / 0 0 0 0 HVR 29 44 28 51 / 10 20 10 0 LWT 28 50 28 49 / 0 20 20 10 && .TFX WATCHES/WARNINGS/ADVISORIES... High Wind Watch from Tuesday morning through Tuesday evening for East Glacier Park Region-Eastern Glacier, Western Toole, and Central Pondera-Northern High Plains-Southern High Plains- Southern Rocky Mountain Front. High Wind Watch from Tuesday morning through Tuesday evening for Cascade County below 5000ft-Judith Basin County and Judith Gap- Upper Blackfoot and MacDonald Pass. && $$ http://www.weather.gov/greatfalls