Heat wave focus shifts to the Southeast, Mid-South, andcentral/southern Plains into midweek......Severe storms and flash flooding possible for portions of the UpperMidwest into Monday night, shifting a bit south Tuesday......Monsoon-like conditions persist for the Southwest/Four Corners Region...A broad upper-level ridge building over the west-central U.S. willcontinue to produce potentially hazardous heat over the next few days.Forecast high temperatures will continue to soar into the upper ...