High Wind in Beaverhead and Western Madison Below 6000ft, Montana

ASOS station KDLN measured multiple gusts in excess of 58 mph, including a peak gust of 97 mph at 931 AM. Power to the ASOS and surrounding community was lost as this peak gust occurred, resulting in limited observations elsewhere. Two other reports were received from the Dillon area stating that a large tree was uprooted and that the wind caused a greenhouse to collapse.

Robust low to mid level flow westerly flow associated with a potent shortwave and attendant cold fronts resulted in a prolonged period of high-end winds and gusts across the entire region Dec 17 into the 18th. Multiple gusts in excess of 90 mph were observed in populated areas, with a peak observed gust of 104 mph west of Bynum. Prolonged power outages were observed across the region, mostly due to trees being damaged/falling over completely. Additional societal impacts included extremely difficult to impossible travel conditions, which prompted a Civil Emergency Message for areas along the Rocky Mountain Front the afternoon of the 17th.