One to two inches of rainfall was widespread through the Plains on Tuesday, and there were isolated reports of more than 3 inches in the central Plains. This rainfall was caused by a slow-moving north-south frontal system with a good fetch of moisture ahead of it. Another system which moved into the Northwest brought mainly around 1/2 inch of rain to mainly western Washington.
The central U.S. frontal system will focus most of its energy and rainfall along the Gulf Coast during the next three days, with up to 4 inches of rainfall possible there, moving slowly eastward. The northwestern U.S. system will move quickly eastward to the western Great Lakes by Wednesday night, but little precipitation is expected with it. A more potent system will develop in the western Plains by Friday, and this could bring moderate snowfall to the higher elevations of the Northern Rockies late this week.