As a relentless heat wave continues to bake the western United States, life-threatening temperatures are poised to spread eastward, bringing scorching heat to the East Coast from Sunday through Wednesday. This development comes amid ongoing record-high temperatures in the West, where cities like Las Vegas and Sacramento have already faced extreme heat.
On Thursday, Las Vegas experienced its sixth consecutive day of temperatures at or above 115 degrees, peaking at a blistering 118 degrees. Sacramento saw temperatures reach 113 degrees, while Salt Lake City hit 106 degrees. Forecasts indicate that Las Vegas could soar to 115 degrees again on Friday, with Phoenix reaching 116 degrees and Sacramento hitting 111 degrees.
This weekend, the extreme heat will stretch from the Southwest into the Rockies and the Plains. Denver is under a heat advisory, with temperatures potentially exceeding 100 degrees, and an excessive heat watch has been issued as far east as Omaha, Nebraska, where the heat index could climb to 112 degrees.
By early next week, the heat wave is expected to move further east, bringing dangerously high temperatures to cities along the East Coast. Forecasts predict the heat index could reach 101 degrees in Atlanta and New York City, 105 degrees in Philadelphia, and 107 degrees in Raleigh, North Carolina, by Tuesday. Record highs are possible from Atlanta to Washington, D.C., to New Hampshire.
The implications of this heat wave are severe. Extreme heat poses an acute public health threat and can cause significant economic losses by disrupting infrastructure and increasing heat-related illnesses. Already, more than two dozen fatalities have been reported in the West, and this number is likely an undercount, according to the Washington Post. Fatalities have also occurred in Washington, D.C., where heat indices have sometimes exceeded 110 degrees.
The unusually strong heat dome dominating the weather pattern across the West is partly to blame. This heat dome is unlikely to loosen its grip entirely, even as the extreme heat spreads to other parts of the country. NOAA data shows that many regions, including the Southwest, Midwest, South, and East Coast, will continue to experience high heat through mid-July.
Human-caused climate change has significantly increased the likelihood and severity of heat waves, making them longer-lasting and more intense. According to the Climate Shift Index from Climate Central, human-induced climate change has made daily high and low temperatures in much of the West at least five times more likely compared to pre-industrial levels.
The ongoing heat wave has shattered hundreds of daily temperature records, including both daytime highs and overnight minimum temperatures. All-time records have fallen in several locations, including Palm Springs (124 degrees), Las Vegas (120 degrees), and Redding, California (119 degrees). The duration of the extreme heat is particularly notable; Las Vegas recently broke its record for the longest stretch of days with temperatures above 115 degrees.
The National Weather Service has emphasized the extreme risk of heat-related illnesses for many people, particularly those without access to adequate cooling or hydration. "Be sure to follow proper heat safety, which includes staying hydrated, wearing light clothing, avoiding outdoor activity, and using air conditioning," the Weather Service advised.
June was the second-warmest month on record in the Lower 48 states, according to NOAA data, with 24 million people experiencing their warmest June in terms of overnight minimum temperatures. This lack of cooler temperatures at night increases the risk of heat-related illnesses, as it deprives people of the ability to cool down and recharge.
Many cities, including Raleigh, Atlanta, Baton Rouge, Corpus Christi, Phoenix, Flagstaff, Las Vegas, Fresno, and Sacramento, are on track to have their hottest summers on record. Given current temperature trends, these cities are likely to solidify their rankings as the summer progresses.
