Parts of the northern Rockies and Upper Midwest should see more scattered thunderstorms Tuesday into Tuesday night. Any severe thunderstorms should be few in number and limited in scope. The next threat of more widespread severe thunderstorms returns by Wednesday and Thursday as the next southward dip in the jet stream pivots out of the Rockies into the Plains. A corridor of warm, moist, unstable air should set up from the southern and central Plains to the western Great Lakes by then. It does not appear this will be a destructive, widespread tornado outbreak, as happened last week in the South. The peak day for both areal coverage and intensity of severe thunderstorms appears to be Thursday. More