Dangerous Conditions From Historic Heat Wave in St. Louis and More Hot Summers Expected

    By Kathleen Berger, Executive Producer for Science and Technology

    The historic heat wave roasting St. Louis for several days in a row became some of the hottest conditions St. Louis has ever experienced. The unbearable heat and high humidity took its toll the week of August 20th.

    “For instance, in St. Louis today on this particular day (August 23rd), the temperature – I’m looking up at the thermometer – reads 96 degrees. The heat index, however, is 116 degrees. It feels like it’s 20 degrees warmer, because when I go outside, the air is so humid and muggy that my body can’t cool off by sweating,” said Michael E. Wysession, PhD, Professor of Earth, Environmental, and Planetary Sciences at Washington University in St. Louis.

    Wysession said the August heat and humidity in St. Louis is from this summer’s heat dome in the Southern U.S. extending into the Midwest.

    “The heat dome in the Southern U.S. has stayed locked in. And in this case, even though the heat dome has shifted some days and we don’t feel it in St. Louis at all, some days it does extend right up north past us.”

    Wysession is closely observing the historically hot summer.

    “We’re most familiar with the heat dome that has been sitting over, sort of, the South Central U.S., but there have been three other heat domes. There’s one in the Atlantic and one in North Africa and one in Asia,” he explained. “A heat dome is a case where the air currents keep a particular mass of hot air pushed down in a particular region of the Earth.”

    The month of July 2023 became the Earth’s warmest month on record. And Wysession said he expects 2023 may become the Earth’s warmest year on record. Wysession explained the dangerous heat is from global warming.

    “Most of that is due to the greenhouse gases in the atmosphere. And those have come from burning fossil fuels – coal, oil and natural gas.”

    When the summer of 2023 ends, Wysession said it’s not over. More dangerously hot summers are expected.

    “Climate forecasting is very analogous to weather forecasts,” he said.

    Wysession explains in HEC Media’s video story.