FRI 08 JUN 2018We headed north after lunch in Chadron (NE) across the border towards Buffalo Gap (SD) towards a supercell that had developed over the Black Hills northwest of Rapid City (SD). Some of the CAMs (convection allowing models) were suggesting that this storm would weaken as it drifted away from the mountains, while new storms were expected to fire up well to the east.
|Hand drawn surface analysis at 15z (09:00 MDT). Isobars black, isodrosotherms green|
|SPC Tornado Probability Forecast|
On the SE side of the storm complex, a nice gust front was visible as this portion of the storm bowed out. We ambled southwards back over the border towards Valentine (NE), with the storm, now forming a squall line, very slowly drifting southeastwards towards us. The storms were very active with lightning, but most was inter-cloud or hidden in the wall of rain - with, by this stage, very little cloud-to-ground lightning, and hence not much worth taking a photo of.
|Gust front to the west of Mission (SD)|
|Mammatus to the south of Valentine (NE)|