Showers and thunderstorms will wind down tonight with the loss of daytime heating. Expect plenty of sunshine with temperatures reaching close to their seasonal averages. An active weather pattern will emerge beginning Wednesday. A large trough will develop across the Pacific Northwest, and out ahead of this a southerly flow will develop. This will allow plenty of moisture from the south to push north into the Dakotas, with the air turning noticeably muggy. The energy of the jet stream will help to fire off thunderstorms, particularly across eastern Montana. These storms could push east into North Dakota, and with the amount of instability in the atmosphere, could remain strong to severe. Confidence at this point is not high on where storms will actually occur, nevertheless it needs to be paid attention to. In addition, high heat and humidity will lead to very hot heat indices, with temperatures only cooling off slightly during the night.
-Meteorologist Dave Holder