The zone from the central Plains to parts of the Mississippi and Ohio Valley to the Appalachians will be in the crosshairs of repeated downpours and the likelihood of flash flooding into next week, AccuWeather meteorologists warn. There will be some extension of flooding downpours into parts of the Atlantic Seaboard as well. First, an injection of tropical air will occur over the Mississippi Valley into this weekend as a tropical rainstorm along the north-central Gulf coast moves inland and is