Heavy rain and flash flooding concerns across the northern Plains tothe upper Midwest......Focus for record hot temperatures will shift into the Mid-Atlantic bySaturday......Heat building over much of the West...Tropical Storm Alberto made landfall in Mexico this morning and continuesto spiral rainfall into South Texas, which will slowly diminish intoFriday. Some of the tropical moisture from Alberto will be drawn northwardand energize the scattered showers and thunderstorms from the southern...