By Kashmira Konduparty
A powerful heat dome is expected to bring dangerous and potentially record-breaking temperatures to much of the central and eastern United States through the Independence Day weekend, with forecasters warning that millions of Americans could face life-threatening heat and high humidity.
The National Weather Service said the sprawling high-pressure system will trap hot air over a large portion of the country, pushing temperatures into the upper 90s and low 100s across many states. Combined with high humidity, heat index values could reach between 100 and 115 degrees Fahrenheit in some areas, creating hazardous conditions for outdoor activities during one of the busiest travel weekends of the year.
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More than 130 million people are expected to experience moderate to extreme heat risk as the weather system expands across the Midwest, Great Lakes, Mid-Atlantic and parts of the Southeast. Cities including Chicago, St. Louis, Washington D.C., Philadelphia, New York and Boston could approach or break daily temperature records later this week.
North Carolina and Ohio are among the states expected to see especially dangerous conditions. In North Carolina, a forecaster warned that temperatures could climb into the triple digits by midweek, with heat index values exceeding 106 degrees in some locations. Overnight temperatures are also forecast to remain unusually warm, reducing opportunities for the body to recover from daytime heat exposure.
In Ohio, the NWS has issued heat advisories for parts of the state, warning that “feels like” temperatures could surpass 100 degrees through Thursday. Officials have cautioned that prolonged exposure to the heat increases the risk of dehydration, heat exhaustion and heat stroke, particularly for older adults, young children, outdoor workers and people with chronic health conditions.
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Meteorologists said the heat dome will likely peak around Thursday and Friday before lingering into the July 4 holiday weekend. While some areas of the Midwest and Northeast could see modest relief later in the weekend as thunderstorms develop, much of the South and Mid-Atlantic are expected to remain significantly warmer than average.
Health officials are urging residents to stay hydrated, limit strenuous outdoor activity during the hottest part of the day and spend time in air-conditioned buildings whenever possible. They also advised people to check on elderly neighbors and never leave children or pets inside parked vehicles, where temperatures can rise rapidly.