NEW : No break from the heat week 's end , says The National Weather Service . the National Weather Service declared excessive heat warnings Sunday for several thousand states . High humidity has driven up heat indices , making it feel as hot as 126 degrees . The extreme heat is forecast to move east by Monday , affecting the East Coast .
NEW : No break from the heat Monday , says the National Weather Service . The National Weather Service declared excessive heat warnings Sunday for 14 states . High humidity has driven up heat indices , making it feel as hot as 126 degrees . The extreme heat is forecast to move east by week 's end , affecting the East Coast .