Flooding and severe weather expected as storms continue across the East

Hot and humid conditions will once again grip the Mid-Atlantic and Southeast today, while rounds of thunderstorms bring the threat of flo oding to parts of the eastern United States. Severe thunderstorms, heavy rainfall, and flash flooding concerns remind to parts of the Mid-Atlantic through Monday, while additional storms develop across the Northern Plains, Upper Midwest, and portions of the western United States. Severe Weather Threat The greatest threat on Sunday will be across the northern Mid-Atlantic, where a frontal boundary stretching from the region into the Great Lakes and central Plains will serve as the focus for widespread showers and thunderstorms. The Storm Prediction Center has placed portions of the northern Mid-Atlantic and Northern Plains under a Slight Risk (Level 2 of 5) for severe thunderstorms through Monday. Slight Risk: over portions of the Mid-Atlantic, northern North Dakota, and northwest/west Texas Storms could produce frequent lightning, damaging wind gusts, large hail, and a few tornadoes. The strongest thunderstorms are expected to develop during the afternoon and evening as warm, humid air fuels the unstable atmosphere. In addition to the severe weather threat, heavy rainfall is expected to create a significant flash flooding risk. The Weather Prediction Center has issued a Moderate Risk (Level 3 of 4) for excessive rainfall across parts of the northern Mid-Atlantic on Sunday Excessive rainfall is possible over parts of the Northeast, Mid-Atlantic into Southern New England on Monday. Slow-moving storms may dump heavy rain in a short amount of time, increasing the risk of flash flooding in urban areas, along roadways, near small streams, and in other low-lying locations. The unsettled pattern will continue into Monday as the frontal boundary shifts east. Showers and thunderstorms are forecast to spread across the Mid-Atlantic into southern New England, where additional heavy rainfall could lead to localized flash flooding. Related article Sizzling heat will bake the South while severe storms are set to threaten the North during the first week of July While the severe weather threat is expected to diminish somewhat, portions of the Mid-Atlantic and Upper Midwest will remain under a Marginal Risk (Level 1 of 5) for isolated severe thunderstorms capable of producing damaging winds or hail. Elsewhere, another cold front moving through the Northern High Plains and Great Basin will trigger scattered showers and thunderstorms from the northern Rockies into parts of Washington state. As the system advances eastward on Monday, storms are expected to expand into the Northern Plains and Upper Midwest. Moisture surging into the Great Basin will also help spark afternoon and evening thunderstorms through Monday, while the combination of daytime heating and abundant humidity will fuel the development of scattered storms along the Gulf Coast and across Florida.