Another intense heat wave this week threatens to increase health risks as nighttime temperatures remain high. According to the National Weather Service, over 90 temperature records nationwide are likely to be matched or surpassed by Wednesday. The majority of these records will involve overnight temperatures, presenting significant health concerns. Experts indicate that high nighttime temperatures pose more danger than daytime heat.
Unexpectedly Hot Start to Summer
Summer has started with extreme heat for many parts of the U.S., worsened by a persistent heat dome expected to cover much of the country. Recent weeks of scorching temperatures have contributed to several heat-related deaths in New Jersey and have intensified wildfires in the West.
No Respite During the Nights
In cities like Fort Lauderdale, Miami, Tampa, Galveston, and Charleston, temperatures won’t drop below 80°F (27°C) overnight. In typically cooler regions of the Midwest and Northeast, such as Fargo, International Falls, and Portland, nighttime temperatures will stay above 70°F (21°C). These high temperatures at night can be more hazardous than daytime heat.
Why High Night Temperatures Are Dangerous
High temperatures at night prevent the body from cooling down, raising the risk of heatstroke and cardiac stress, especially in elderly and vulnerable individuals. Marshall Shepherd, a meteorology professor at the University of Georgia, notes that the health effects are more severe due to the lack of cooling.
“That’s where the health outcomes are amplified, particularly for the elderly and vulnerable communities,” he says.
Invisible Dangers of Continuous Heat
Kristie Ebi, a public health and climate scientist, emphasizes that the body needs time to cool. Without cooler nights, symptoms such as heavy sweating, muscle cramps, and headaches can worsen over consecutive days.
“Mortality starts the second or third day” due to prolonged heat exposure, Ebi says.
Proactive Measures for Coping
During a heatwave, taking proactive steps is essential. Look for signs like heavy sweating and headache. Use air conditioning, or cool down with a cold towel. Check on vulnerable friends and family. Whether pregnant or with health issues, they may struggle with the heat.
Finding Relief Without Air Conditioning
For those without air conditioning, relief can be found in public spaces or at home. Visit air-conditioned venues like libraries or malls. Use fans, and keep skin moist with water. Resting feet in cold water and soaking clothes can also help. Remember to stay hydrated by drinking plenty of water.
Contributions to this report by Associated Press reporter Seth Borenstein.