847 FXUS65 KTFX 052105 AFDTFX Area Forecast Discussion National Weather Service Great Falls MT 305 PM MDT Fri Jun 5 2026 .KEY MESSAGES... - Scattered showers and thunderstorms on Saturday then turning much cooler with additional showers Sunday. - Breezy conditions through the weekend, particularly along the Rocky Mountain Front and across Southwest Montana. - An active pattern is expected next week with daily chances for precipitation starting Tuesday. && .DISCUSSION... - Meteorological Overview: A low-amplitude upper level ridge transits the Northern Rockies and MT today bringing the warmest and driest conditions of the next seven days before an upper level low/trough, currently offshore of BC moves into the NW US this weekend. Breezy west to southwest winds develop today as flow aloft shifts more southwesterly behind the exiting upper ridge with gusts in excess of 35 mph primarily confined to areas along the Rocky Mtn Front as the surface pressure gradient across the Rockies increases today and over portions of SW MT where deeper afternoon mixing is achieved. A Pacific cold front crosses the Northern Rockies Saturday with moisture gradually increasing within the southwest flow aloft. A few showers develop behind the front across north-central/central MT early Saturday with showers and a few thunderstorms tracking northeast from southwest MT Saturday afternoon through eastern portions of north-central MT Saturday evening. A stronger shortwave rotates through the trough across the Rockies Saturday night through Sunday, spreading much cooler temperatures across the area along with more widespread showers and perhaps a few thunderstorms. Snow levels fall to around 7000 ft Sunday and potentially as low as 6000 ft with the coldest air aloft passing across the area Sunday afternoon. This could bring some snow as low as passes across central and southwest MT, however afternoon timing will limit the potential for accumulation. Gusty west winds and afternoon temperatures in the 50s (upper 30s/40s in the mountains) on Sunday may impact those with outdoor recreation plans in the mountains. Clearing is expected Sunday night as the trough lifts out of the area with overnight low temperatures reaching the 30s to around 40 across most of the forecast area. A fairly active/unsettled weather pattern persists next week with mainly dry conditions and seasonable warmth Monday before the next larger scale upper trough/low drops into the western US for the remainder of the week. While there is good overall agreement on the broader trough and increasing confidence in widespread precipitation, there is still a fair amount of variation in timing and placement of the upper low with probabilities for 0.50" or greater precipitation amounts (Tues-Thurs) ranging from 50-70% across much of the area. Hoenisch - Forecast Confidence & Scenarios: Thunderstorms Saturday: For our CWA, the highest instability will be across Southwest Montana into portions of Central Montana as far north as Fergus county. The 18Z HRRR suggested CAPE was less than 800 J/kg in the region which is enough to do something but not enough to create significant problems. One or two storms might attempt to misbehave but in general most of the activity is expected to stay on the low-end of things. Precipitation Sunday: More widespread precipitation is expected on Sunday. The highest probabilities for greater than a tenth of an inch lie south and east of a line between Havre to Great Falls to Missoula. For locations in central Montana such as the Little Belts, there is a 90% chance of at least 0.25" and a 75% chance of at least 0.5". Widespread flooding is not expected with this event, however, there is a possibility for some creeks might rise and low-lying, flood-prone areas might have some ponding. But there is no larger risk at this time. This will be monitored in case anything changes. In terms of snow, there is still some uncertainty as to how much will be able to accumulate. Right now, snow levels are expected to drop to around 6,000-8,000 feet which will allow for at least a dusting across much of the higher elevations. But finding amounts greater than 2 inches will be a challenge as As to whether locations below 6,000 feet might see snow that is still up for debate. With the timing of the precipitation still expected to be Sunday afternoon, it is unlikely that any of the valleys of Southwest Montana will see snow, however, it is not completely out of the realm of possibilities either. With this forecast package, snow levels went down slightly but not enough to increase confidence and the going thought is that, even if a couple flurries end up falling, it is highly unlikely there will be accumulating snow at or below pass level. But given the uncertainty, there is still always a chance that things could change from now until Sunday. -thor && .AVIATION... 05/18Z TAF Period VFR conditions are expected to prevail at all terminals through the period. Westerly flow aloft turns southwesterly later today and tonight with increasing high clouds this afternoon through tonight. Breezy southwest winds develop at most terminals this afternoon with gusts as high as around 30kts at KEKS and KCTB. Hoenisch/thor && .PRELIMINARY POINT TEMPS/POPS... GTF 49 72 46 59 / 10 20 50 60 CTB 44 66 39 57 / 0 30 10 30 HLN 49 74 45 59 / 0 30 40 60 BZN 46 80 44 62 / 0 20 40 80 WYS 39 76 41 62 / 0 10 20 40 DLN 46 78 44 61 / 0 20 30 60 HVR 48 77 45 64 / 20 20 50 50 LWT 46 77 42 58 / 10 20 50 80 && .TFX WATCHES/WARNINGS/ADVISORIES... None. && $$ http://www.weather.gov/greatfalls