Area Forecast Discussion
Issued by NWS Billings, MT
Issued by NWS Billings, MT
316 FXUS65 KBYZ 150820 AFDBYZ Area Forecast Discussion National Weather Service Billings MT 220 AM MDT Sat Jun 15 2024 .DISCUSSION... Today through Sunday Night... Scattered showers are evident on radar early this morning north and east of Billings. This activity will gradual move east out of the area through the early morning hours. Upstream, there are additional scattered showers that are expected to move through our western areas (west of Billings) through the later morning hours. This morning`s activity is expected to remain weak. By this afternoon, another round of showers and thunderstorms is possible across portions of the area (15-50% chance). This activity will be aided by a more vigorous shortwave aloft that is expected to traverse through northern Montana this evening. Even though the main shortwave will pass to our north, a cold front will pass through our entire area late this afternoon and evening. This cold front will bring gusty NW winds to the entire region, with wind gusts of 20 to 40 mph common. A few isolated to scattered showers and thunderstorms may accompany the front (15-50% chance, highest north of Billings), but this activity should remain relatively weak. The main threat will be localized areas of enhanced winds where these showers and thunderstorms develop. Outside of this frontal activity, stronger storms are also possible (20-30% chance) across far eastern Montana ahead of the front this afternoon where diurnal instability is expected to combine with sufficient shear and atmospheric moisture. The main threat with any storm that develops in this area will be large hail and strong winds, especially under the longer lasting cells. This lines up with the day 1 outlook from SPC which has a slight (2/5) risk for severe thunderstorms in our east today. Stronger southwesterly winds aloft look to move in ahead of the front today as well. This will create windy conditions in the mountains this afternoon, with wind gusts into the 50s (mph) possible over the higher terrain. If you have outdoor plans in the mountains today, including the foothills, prepare and be aware for windy conditions. Sunday will be mostly dry before chances of precipitation increase again during the evening/overnight in southeastern MT with a passage of another (weaker) shortwave (20-45% chance). Chances of precipitation will also increase in western areas during this time as our next system begins to move in from the west (more on this below). Temperatures today are expected to be in the 70s and 80s over western and central areas and near 90 in eastern areas. Sunday will be cooler with temperatures in the 60s and 70s. Arends Monday through Friday... The week ahead will be cooler and unsettled with Pacific trofiness over the area. That said precipitation amounts are significantly lower in the models over the past 24 hours as the core of the system is weaker and tracking further north. This puts our neck of the woods in the drier downsloping wind sector of the system. There will still be a good amount of instability with colder core of upper level air over the region, leading to widespread mean precipitation amounts of .25 to .60 inches across the area Monday into Wednesday, while probabilities for half an inch or more of precipitation range from 20 percent along the southern state line, to 60 percent along the Musselshell river valley. Monday night into Tuesday morning brings the best chance for snow with snow levels dropping to under 7000 feet by Tuesday morning. With precipitation amounts lower, snow accumulations decreased as well. That said, those traveling over the Beartooth Pass or into Yellowstone Park should expect wintry conditions and slick roads from late Monday through at least mid-day Tuesday. Weak ridging will dampen the chance for precipitation Wednesday into Thursday, though there will still be a chance of unorganized afternoon/evening showers and thunderstorms as temperatures warm up enhancing instability in the heat of the day. Another Pacific Trof works into the area Thursday night into Saturday. This system will pull enhance plains moisture into the region ahead of it setting up a better chance for substantial precipitation with shower and thunderstorm activity. Temperatures will be mainly in the 60s Mon/Tue,70s for the rest of the week. Chambers && .AVIATION... Light shower activity will persist over various parts of the area through the morning hours. By mid day expect Thunderstorms to develop over area mountains and move east-northeastward. Latest HRRR and NCAR models suggest strongest storms may develop around 19z over the Bighorn mountains and push east-northeast across SE Montana with damaging wind gusts to 50kts the main threat. Winds outside of Thunderstorms will be gusty (35 to 50kts) in the mountains and foothills by 18-20z, spreading into the lower elevations as a Pacific cold front moves into the area 21-23z. These gusty west to northwest winds late afternoon will linger into the evening hours, especially east of Billings. The west/northwest winds will bring an end to convection as they move through. Chambers && .PRELIMINARY POINT TEMP/POPS... Tdy Sun Mon Tue Wed Thu Fri ------------------------------------------------------- BIL 083 049/072 049/062 044/064 045/073 051/077 056/077 2/W 20/B 27/W 74/T 12/T 23/T 24/T LVM 076 038/068 041/056 036/060 037/069 043/074 049/075 5/T 30/N 38/T 74/T 23/T 33/T 24/T HDN 087 049/073 050/067 044/065 045/074 051/079 056/079 1/B 20/B 37/W 84/W 12/T 32/T 34/T MLS 088 051/072 051/064 047/064 045/072 052/077 056/077 2/W 30/U 36/W 94/W 22/W 43/T 44/T 4BQ 092 051/073 052/067 047/063 044/072 052/078 056/076 2/T 20/B 45/W 83/W 23/T 43/T 44/T BHK 090 049/072 047/065 046/063 042/071 050/075 054/076 3/T 50/N 44/W 84/W 12/W 43/T 44/T SHR 089 046/072 045/070 042/063 042/072 048/078 052/077 1/B 10/B 45/T 63/T 23/T 33/T 35/T && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$ weather.gov/billings