Area Forecast Discussion
Issued by NWS Billings, MT
Issued by NWS Billings, MT
976 FXUS65 KBYZ 010650 AFDBYZ Area Forecast Discussion National Weather Service Billings MT 1250 AM MDT Mon Jul 1 2024 .UPDATE... The threat for severe thunderstorms in eastern Montana has diminished, as a result, Severe Thunderstorm Watch 493 for Custer, Fallon, and Rosebud Counties has been EXPIRED. No other updates made to the forecast. Matos && .DISCUSSION... Rest of Today through Monday Night... There are no big changes to today`s thunderstorm potential outside of the SPC`s Slight risk for severe thunderstorms getting pulled west through Livingston this morning. Showers and thunderstorms, some becoming strong to severe, are still expected to form around the western mountains and move east/northeast through central Montana this afternoon and evening. By midnight, this activity is expected to be moving into the Dakotas. While isolated showers and weak thunderstorms are ongoing west of Livingston early this afternoon, the main event looks to get started in the west around 2-4 PM MDT. The latest model guidance continues to suggest thunderstorms will track north of Billings this evening, but there remains a chance (30%) that Billings could still see a thunderstorm. With any thunderstorm that forms today, wind and hail are the main threats, with heavy rain and frequent lightning being secondary threats. The wind threat is the most concerning at this time with gusts up to 75 mph possible. As common with storms out here, these strong winds will likely also be felt outside of the storm itself, so areas like Billings could see increased winds without ever getting a storm overhead. In addition, today`s storms are following a cold front so locally enhanced winds from convection along the front is certainly a concern. One thing to note, as thunderstorms move into east central Montana this evening, some could intensify as they move into a better environment. After today`s activity, periods of showers and weaker thunderstorms look to develop tonight through Monday. With this activity, a few stronger storms are possible in southeastern Montana Monday afternoon. This activity will be limited by weaker instability though, so the threat for severe weather remains marginal. Monday night into Tuesday morning, snow levels are expected to drop around 10,000 feet in the mountains. This could lead to wet light snow at the highest peaks of the Beartooth/Absaroka Mountains, including the Beartooth Highway. Arends Tuesday through Sunday... Active weather will persist for much of the extended period. In fact, current indications are that an unsettled NW flow will last thru next weekend...a change from how things looked the past few days. Broad troffing/cyclonic flow and below normal heights will result in a daily chance (30-50%) of showers and thunderstorms Tuesday thru Thursday. The progressive nature of the flow will limit severe potential, but w/ seasonably low freezing levels just about any thunderstorm will produce small hail. Temps should max out in the 70s Tuesday & Thursday, but may eke into the lower 80s Wednesday per a brief period of pre-frontal warming. The 4th of July may turn out to be the coolest day of the week (low-mid 70s) and could also have breezy NW winds along with showers on the back side of a shortwave. That said, shower chances and wind should decrease in the early evening, resulting in comfortable (if not a bit chilly) conditions for Independence Day celebrations. Freezing levels should fall enough to produce a risk of snow showers Wednesday night into Thursday over the highest elevations of the Crazy & Beartooth-Absaroka Mountains. GFS/EC show wet bulb zero heights to 9.5-10kft, which if accurate would mean snow showers over Beartooth Pass above Vista Point. Something to be prepared for if you have outdoor recreation plans in the mountains this week. Latest snowfall probabilities for 1+ inches over the Beartooths are non-zero. Friday should trend warmer & drier as heights start to build, but additional energy in the NW flow may bring a few showers (especially in the east and southern mountains). To highlight today`s biggest change to the extended forecast, ensembles then show a strong Pacific coast high building far enough west to allow for more shortwave energy to drop out of western Canada into our region this weekend. There is plenty of spread here, of course, but it should be noted that the cluster analyses show highest probability of solutions on the cooler & wetter side. So, look for more potential showers & thunderstorms next weekend, w/ temps no warmer than normal (and possibly cooler). Overall this is shaping up to be a very comfortable start to July, with any potential "dog days" heat pushed back until after the 8th or 9th. JKL && .AVIATION... For the remainder of the afternoon, look for scattered strong thunderstorms to develop west of KBIL, possibly affecting KLVM-K6S0-K3HT with brief MVFR, strong wind gusts and possible hail before 00z. Thunderstorms associated with a cold front will arrive around 00z for KBIL and progress eastward between 00z and 06z. Primary hazards w/ these storms are strong wind gusts (45-65 knots) and hail, potentially impacting KBIL-KMLS-KBHK this evening. The potential for thunderstorms is much lower in far southeast MT and near Sheridan (but this will need to be watched). Additional showers and some embedded weaker tstorms are expected late tonight and Tuesday. Mountains will be occasionally obscured. TS POTENTIAL TIMES TODAY: KBIL: 23z-03z (20% chance, risk of strong wind & hail) KLVM: 20z-06z (40% chance, risk of strong wind & hail) KMLS: 02z-06z (40% chance, risk of strong wind & hail) KSHR: 22z-03z (10% chance, low risk of strong wind) JKL && .PRELIMINARY POINT TEMP/POPS... Mon Tue Wed Thu Fri Sat Sun ----------------------------------------------------------- BIL 060/079 056/079 055/081 053/075 053/083 057/085 058/083 35/T 44/T 14/T 55/T 21/U 12/T 12/T LVM 052/075 048/075 048/077 046/073 046/082 051/084 051/082 55/T 63/T 13/T 44/T 21/U 12/T 12/T HDN 057/079 055/079 051/082 051/075 049/083 053/085 054/084 25/T 54/T 14/T 55/T 21/U 12/T 12/T MLS 061/078 056/078 054/082 055/073 054/081 057/085 057/083 24/T 13/T 14/T 56/T 31/U 12/T 11/U 4BQ 061/079 056/077 053/084 054/073 053/080 056/085 056/083 17/T 34/T 03/T 55/T 22/W 12/T 11/U BHK 059/079 053/077 052/081 051/072 051/078 053/082 053/082 45/T 13/T 03/T 56/T 32/T 12/T 11/U SHR 055/075 050/076 048/081 048/073 047/080 051/083 051/082 18/T 76/T 22/T 44/T 22/T 12/T 12/T && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$ weather.gov/billings