Scattered showers and isolated thunderstorms formed across the southern Absaroka Mountains near Washakie Needles in the early afternoon and then moved east across the southern Big Horn Basin. The showers and thunderstorms weakened fairly quickly as they moved east into Washakie County. However the extreme heat and low surface relative humidity made conditions favorable for dry microbursts. A dry microburst is a downdraft from a shower or thunderstorm that occurs from rain evaporating quickly in the dry air. Dry microbursts usually affect an area of less than 2 miles wide with little or no rain reaching the ground. In addition, little or no lightning might be present at the time of the dry microburst.
Estimated winds between 60 and 70 mph affected the Worland area between 315 and 330 p.m. Sunday afternoon. Known damage consisted of 15-20 power poles, several trees were toppled. A patrol car and at least one home were damaged by these downed trees. Also, one window was reportedly blown out at a residence. No injuries were reported.
Here are some damage photos from Worland courtesy of Mr. Yule.