 As heat is the number one weather-related killer each year in the United States. More than tornadoes, hurricanes, and floods. So take the heat seriously. Lots of water, shade, sunscreen, and limit your time outside during the afternoon. It already feels like it's 99 degrees. And in several counties, it could be even more dangerous today with the intense heat. In Calvert, St. Mary's, and Charles counties in Maryland.