An expansive, mid-summer heat wave will continue to dominate the western and central U.S. for the remainder of the week, with some eastward spread of significantly above-normal temperatures late in the week. Triple-digit (100-degree) temperatures will continue through the end of the week in several regions, including the central and southern Plains, occasionally reaching into the mid-South and western Corn Belt. The overnight hours will not offer much relief, with temperatures remaining consistently above 70°F as far north as the central Plains and southern Corn Belt.