WWUS20 KWNS 231958 SEL7 SPC WW 231958 MTZ000-240100- URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 617 NWS Storm Prediction Center Norman OK 155 PM MDT Sun Aug 23 2026 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Central and Southwest Montana * Effective this Sunday afternoon and evening from 155 PM until 700 PM MDT. * Primary threats include... Scattered damaging winds and isolated significant gusts to 80 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...Scattered thunderstorms are forecast to develop and intensify and spread from west to east across the Watch area this afternoon into the early evening. The threat for isolated large hail will accompany a few cells along with a risk for severe gusts. As additional storms develop and outflow congeals into one or more small clusters, an increase in the threat for scattered severe gusts (60 to 80 mph) will probably occur. The severe thunderstorm watch area is approximately along and 75 statute miles east and west of a line from 35 miles north northwest of Havre MT to 50 miles south southwest of Livingston MT. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 70 knots. A few cumulonimbi with maximum tops to 400. Mean storm motion vector 25030. ...Smith