Among cities with the largest annual increases in days that reach 90 degrees Fahrenheit or hotter, there’s McAllen, Texas, with 31.6 more days per year since 1979; Baton Rouge, Louisiana, which had 24.2 more; New Orleans, which had 23.6 more; Miami, with 23 more; and Savannah, Georgia, which had 22.8 more.
In a number of Southern cities, extreme heat days reach far beyond summer months. Miami had 160.6 days extreme heat days on average over the last five years, for example.
Nearly a dozen US cities saw an increase of at least four “danger” days on average since 1979. A “danger” day is when the combined heat and humidity makes it feel like it’s 105 degrees Fahrenheit or hotter. McAllen saw an increase of 21.9 days since 1979, Houston had 9.6 more and Pensacola, Florida, had 5.9 days more, the report found.
doesn’t handle these extremely hot and humid days well, because sweat — your natural cooling mechanism — doesn’t evaporate when it’s really humid and you can’t cool down as well. It can also be hard to breathe.
For both conditions, “danger” days and “heat index” days, it can be dangerous to exercise outside and can lead to heat exhaustion
and heat stroke.
A number of sporting events around the world have had to cancel due to high temperatures, including the New York Triathlon in July. Last year, for the first time in the US Open’s history, an extreme heat policy was implemented to help male tennis players cope with temperatures around 100 degrees Fahrenheit in New York.
Standards vary on when practices or games are canceled and not every school or professional team has the proper equipment
to measure the true heat/humidity conditions on a practice field, according to the report.
Since 1995, 64 football players alone have died from heat stroke and 90% of them died during practice, an earlier study showed.
The rate of football heat stroke deaths fell in recent years, a decline researchers said supported continued efforts to train coaches, players and others about practicing in heat and hydrating properly.
The new report’s authors encourage coaches to follow the National Athletic Trainers’ Association
recommendations to limit players’ risk of practicing in the heat, including keeping fluids on hand at all times, encouraging rest breaks and watching for signs of heat-related illness.