Severe thunderstorms and flash flooding possible across portions of thecentral Plains and Midwest today......Unsettled weather with the potential for heavy rain and strong stormsenter the Lower Great Lakes and Upper Ohio Valley on Saturday......Dangerously hot conditions will continue from parts of the southernPlains to the Southeast this weekend...A low pressure system is pushing across the northern and central Plainsthis afternoon. The low pressure center is moving east along theU.S.-Canada...