Area Forecast Discussion
Issued by NWS Billings, MT
Issued by NWS Billings, MT
115 FXUS65 KBYZ 162135 AFDBYZ Area Forecast Discussion National Weather Service Billings MT 335 PM MDT Sun Jun 16 2024 .DISCUSSION... Through Tuesday Night... Breezy west to northwest winds are beginning to decrease and turn more north to northeast this afternoon as an upper low crosses southern Canada and an associated cold front approaches. A weak shortwave will lift north and east through Wyoming tonight bringing isolated to scattered showers over portions of southeast MT (15-30%). Precipitation chances begin to increase overnight over the west as an upper trough and associated low approach the region. Shower and thunderstorm chances will increase from west to east on Monday (30-90%, highest west), as the aforementioned trough moves into the region. Central and eastern areas will likely remain dry for most of the day Monday, before easterly flow and instability working into the region begin generating showers and thunderstorms over these areas in the afternoon. MUCAPE values climb up to 1000-2000 J/kg in the afternoon with deep layer shear of 40-60 kts during the afternoon over southeast MT. SPC currently has a Marginal risk for severe thunderstorms for these areas on Monday, with hail and wind the main threats. Periods of showers and thunderstorms are progged through Tuesday as the low lifts north and east through Montana. Uncertainty still exists with the track of the low, with some guidance taking a more northerly track and others bringing the low across southern MT. A northerly track would likely mean less precipitation and warmer temperatures, so this is something to continue to watch. Have continued with an ensemble approach to precipitation amounts. Showers will decrease by Tuesday evening as the system lifts out of the area. At this time, much of the area will see between 0.25 to 1 inch of precipitation (rainfall and melted snowfall) through Tuesday. Locally higher totals are possible in the western mountains and with thunderstorms. Latest NBM probabilities for 0.25 inches or more range from 80% or greater in the north to 40-60% in the south outside of the mountains. The probability of 0.50 inches or more range from 30-70%, highest in the west and the north. Cooler temperatures will move into the area as the system lifts into the region, and snow levels will fall down to near 7000 feet by Monday night. Several inches of snowfall are possible in the mountains, including over the Beartooth Highway. Currently up to 4 inches of snowfall are forecast for the highway starting Monday afternoon, and continuing at times through Tuesday. We have gone ahead and issued a Winter Weather Advisory for the Beartooth Highway from Monday afternoon through Tuesday with this forecast package. Monitor the forecast and prepare for wintry conditions if you are planning to recreate in the high country. Temperatures are forecast to range from the 50s to the 70s on Monday, warmest over the southeast, cooling into the 50s and lower 60s across the area on Tuesday. Low temperatures will range from the lower 40s to lower 50s tonight, to the upper 30s to 40s on Monday night. Tuesday night looks to be the coldest with lows in the middle 30s to lower 40s for most locations, lowest over the west. STP Wednesday through Sunday... Wednesday and Thursday look to be mostly dry with warming temperatures as the trough starts to lift and a surface high to our east brings southerly winds and warm air advection. WPC clusters are in good agreement that Friday will seeing troughing return to the region. This will create a low pressure system over the northern plains with easterly winds advecting in plains moisture bringing precipitation chances back to the region. There is currently a lot of uncertainty with the deterministic models as to what this system will look like which is to be expected 5 days out. Overall, with the 12z runs, there seems to be a trend to lower precipitation amounts due to high pressure in the Canadian prairie limiting the northern extent of the low. The 12z ensembles don`t shown a similar decrease in precipitation but this will be something to watch over the next few days. For the weekend, ensembles are showing shortwave ridging coming in raising temperatures into the 80s and possibly 90s with dry conditions. Torgerson && .AVIATION... Winds will continue to decrease for most areas during the overnight tonight. Tonight there could be isolated (20%) showers across the region. Tomorrow around 15Z showers will start to make their way into KLVM and K1KM with showers becoming more widespread across southeast Montana by 21Z. There could be some stronger storms mixed in with these producing small hail and 50kt winds. Torgerson && .PRELIMINARY POINT TEMP/POPS... Mon Tue Wed Thu Fri Sat Sun ----------------------------------------------------------- BIL 051/066 045/061 042/073 049/080 057/078 057/080 056/086 14/W 76/T 11/U 01/B 25/T 43/T 11/U LVM 043/058 037/059 034/070 041/076 048/077 050/081 050/086 29/T 98/T 22/T 11/B 15/T 43/T 11/U HDN 049/069 044/062 038/076 048/083 056/079 055/081 053/087 25/T 86/T 11/U 12/T 35/T 54/T 21/U MLS 052/068 047/060 042/073 050/080 057/078 057/078 055/084 27/T 96/W 21/U 12/T 44/T 64/T 21/U 4BQ 052/072 048/061 042/072 051/079 058/079 058/080 055/084 25/T 93/W 12/T 22/T 45/T 54/T 21/U BHK 048/070 047/060 040/073 047/078 055/076 055/077 051/081 23/T 94/W 11/B 12/T 44/T 54/T 21/U SHR 044/075 040/061 037/073 046/080 054/079 053/080 052/086 25/T 74/T 12/T 11/B 45/T 54/T 21/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$ weather.gov/billings