Wet weather is forecast to persist in the East, heat over the Mississippi and storms are expected to develop in the Northern Plains and Upper Midwest on Tuesday.
A low pressure system moving through eastern Canada will continue pushing a cold front southward through the East. On Tuesday, the system will kick up scattered showers and thunderstorms over the extreme Northeast, as well as the Mid-Atlantic and Gulf states. Strong winds, large hail and periods of heavy rainfall are likely.
Behind this system, a ridge of high pressure builds over the Plains and Mississippi River Valley. The ridge will allow for hot conditions to return to these areas, with high temperatures to reach over 100 from the Southern and Central Plains to the Mid- and Lower Mississippi River Valley. Heat indicies will surpass 110 degrees, thus, heat advisories have been issued across the region.
Meanwhile, in the North, another trough of low pressure will advance eastward off the Northern Rockies. As this system moves into the Northern Plains and Upper Midwest, it will create a warm front that will trigger heavy showers and thunderstorms. Some of these storms will turn severe with large hail, damaging winds and possibly a tornado or two. Flooding will remain of concern for the Missouri River and surrounding tributaries.
Out West, monsoonal moisture lingers over the Four Corners, allowing for more thunderstorms to develop across the deserts of the Southwest in the afternoon and evening hours. A trough of low pressure over the West Coast will create more low clouds and fog along the coasts, with sunny and warm conditions inland.
Temperatures in the Lower 48 states Monday ranged from a morning low of 33 degrees at Truckee-Tahoe, Calif., to a high of 107 degrees at Mineral Wells, Texas.