High Wind in Pennington Plains, South Dakota

A potent short wave moved across the Montana/Wyoming border and into northwestern South Dakota after midnight. A line of thunderstorms developed as the wave moved across northeastern Wyoming and northwestern South Dakota. As the line of storms moved into northwestern South Dakota it encountered more stable and drier air. The thunderstorms quickly dissipated after producing a strong and persistent gust front. Behind the gust front a very tight pressure gradient was established. High winds in excess of 40 mph sustained with gusts to 64 mph were noted over the area. The high winds persisted for few hours before subsiding as the pressure gradient relaxed.