High Wind in Southern High Plains, Montana

Montana Mesonet station Bynum W acebynum measured a 95 mph wind gust on top of many, many gusts in excess of 58 mph. In fact, sustained winds, averged over an hour, peaked at 54 mph. Other sensors to measure gusts of 58 mph or greater or sustained winds of 40 mph averaged over at least an hour include mesonet station HODMT Hodgkiss, mesonet station MCBMT McBratny - MCSCN, AWOS station K1FM Foxtrot, mesonet station DELMT Dellwo (MCSCN), Weather Underground site LF Ranch Main - KMTAUGUS23, Montana mesonet sensor Bowmans Corner NW acebowma, and mesonet station MTBOW Bowmans (MT DOT). Broadcast media shared a post with photos from the Willow Creek Reservoir area showing several damaged buildings. The post described the damage as One house was blown off its foundation and had debris scattered all around. Another prefab house was blown over onto its roof. The post mentioned gusts near 100 mph based on personal weather stations.

A robust trough digging southeastward from the Pacific Northwest brought a belt of strong mid and low-level westerly flow across the majority of the region December 18. Given the favorable timing of the strongest flow and cold front, winds were easily able to mix to the surface. A respectable pressure gradient also developed across the area, which helped a few sites reach high sustained winds. In northeastern areas the wind took longer to develop, eventually needing the surface low to pull away from AB toward SK. This propelled a front through the area that brought both strong winds as well as rain that fell onto very cold surfaces, resulting in slick roads.