The Eastern seaboard will see another active day Sunday. A low pressure system over the northern U.S. will continue tracking eastward as it pulls moist air up from the Gulf of Mexico while the back side pushes a cold front over the Mississippi River Valley.
On Sunday, the front will kick up showers and thunderstorms as it stretches from the Northeast over the Mid-Atlantic States and into the Southeast. Moisture-laden air will turn some of these storms severe, especially since the system has a history of producing strong winds, large hail, heavy downpours and even some tornadoes.
Behind this system, a high pressure ridge is building over the Plains, bringing a short respite from wet weather. Expect sunny skies and warm temperatures across the Central U.S.
High heat will persist in the Southern Plains, with daytime highs reaching over 100 degrees and heat index values up to 115 degrees.
Out West, monsoon moisture over the deserts of the Southwest is heading northward into the Central Rockies, bringing the possibility of more scattered showers and thunderstorms to develop. Some of this moisture may reach into southern California, but thunderstorms are more likely at higher elevations.
In the Northwest, a low pressure trough is expected to dip in from the Gulf of Alaska, bringing clouds, scattered showers and cooler temperatures to the Pacific Northwest.
Temperatures in the lower 48 states ranged Saturday from a morning low of 28 degrees at West Yellowstone, Montana, to a high of 107 degrees at Houston, Texas.
Weather Underground: http://www.wunderground.com
National Weather Service: http://iwin.nws.noaa.gov