FXUS65 KBYZ 020809 AFDBYZ Area Forecast Discussion National Weather Service Billings MT 209 AM MDT Wed Jul 2 2025 .KEY MESSAGES... - Quite warm through Thursday with many locations in the 90s. Areas in the river valleys (Hysham to Miles City) have 70% chance of triple digits today. - Near-normal temperatures return Friday with a daily chance of showers and thunderstorms through the holiday weekend. && .DISCUSSION... Today through Thursday night... Axis of upper ridge over us shifts a little east today opening up a better fetch of moisture in the S/SW flow. In the meantime, southeasterly low level winds will advect in moisture across our plains bumping our PWATs to between 0.85 - 1.00 (inches). A weak impulse is expected to track into SW Montana and then east/northeast through the evening to help initiate convection. Soundings suggest a modest wind threat from any stronger cells that form in the early to mid afternoon, but shear is relatively weak so the hail threat is not very high. Storms will move into a better moisture as they move east in the evening with heavy rain and strong winds possible in a well-mixed environment. Showers will linger late tonight into pre-dawn Thursday near the Dakota border. Another round is expected Friday with a more pronounced perturbation in the SW flow moving up from Wyoming toward SE MT. Recent progs suggest a weakly sheared environment, so only a modest hail threat. However PWATS may be 0.9 to 1.20 (inches) in the east Thursday which could lead to some very heavy rain with stronger cells. We expect today will be the hottest overall day of the week. Highs in the 90s with ensembles indicating a 70% chance of locations from Hysham to Miles City seeing the century mark or better. Temps will be a few degrees cooler Thursday thanks to depressed heights and increased cloud cover. BT Friday through Tuesday... Active weather is forecast through the holiday weekend as the upper level flow becomes more southwesterly behind an exiting upper level ridge. With this, cooler, near normal temperatures and daily afternoon and evening shower and thunderstorm chances are in the forecast. Those with outdoor plans for the holiday weekend should pay close attention to the forecast and remain weather aware. On Friday (the 4th), a robust shortwave trough looks to move through the region during the afternoon into the overnight hours. With this, high temperatures look to remain in the 70s and 80s with a moderate to high chance of precipitation across the area (50 to 80 percent, greatest over the mountains). While lower values of CAPE (250-500 J/kg) should limit the coverage of any strong thunderstorms, general thunderstorms are possible (20 to 40 percent chance). Those with outdoor plans should remember that lightning makes all thunderstorms dangerous. With the passage of the previously mentioned shortwave lingering into Saturday, scattered showers and thunderstorms are forecast on Saturday once again (20 to 50 percent chance). While the daily chances of precipitation remain in the forecast for Sunday into early next week, ensembles suggest the upper level flow may become more westerly. This may cut off some moisture and allow for more downslope, drying conditions. Will have to see how things trend. Arends/WMR && .AVIATION... VFR conditions will prevail. The chance for thunderstorms returns after 19z near KLVM and moves towards KBIL by 21z. Any of these storms could produce heavy rainfall and winds up to 40kts. Mountains will be partially obscured from 18z-04z. BT/WMR && .PRELIMINARY POINT TEMP/POPS... Tdy Thu Fri Sat Sun Mon Tue ------------------------------------------------------- BIL 096 065/091 063/086 058/077 055/083 058/087 059/0913/T 22/T 55/T 75/T 21/U 11/U 11/U LVM 091 056/086 053/080 049/075 048/081 050/086 052/089 2/T 25/T 57/T 86/T 22/T 21/U 11/U HDN 099 063/092 063/087 057/079 052/085 057/089 057/092 2/T 22/T 54/T 75/T 21/U 21/U 11/U MLS 099 067/095 067/088 061/078 055/083 059/089 061/091 2/T 31/B 52/T 65/T 31/U 21/U 21/U 4BQ 094 068/092 066/085 061/079 055/081 059/087 062/089 2/T 31/B 52/T 54/T 31/U 21/U 21/U BHK 092 065/095 064/084 057/077 051/078 054/084 058/088 1/U 31/B 52/T 55/T 31/U 22/T 21/U SHR 095 059/088 059/084 053/079 048/082 052/086 053/088 2/T 23/T 55/T 54/T 21/U 12/T 11/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...Heat Advisory in effect from 9 AM this morning to 9 PM MDT this evening FOR ZONES 30>32-173. WY...None. && $$ weather.gov/billings