 A frontal system will cause showers and thunderstorms to develop, some of which may be strong to severe from the Great Lakes into the central and northern plain states today. Afternoon showers and thunderstorms will be developing over parts of the northeast as well as the Gulf Coast. We'll see monsoonal moisture produce a few showers and thunderstorms later today across parts of the southwest. Fair weather will prevail across parts of the west and the Pacific Northwest. With your three-day forecast, Carolyn Bloomberg 1130.