NEW YORK — Once again, the U.S. East was enveloped in an intense heatwave on Wednesday, setting new temperature benchmarks even as forecasts promised a sharp drop in the coming days. Anticipated temperature plunges in several regions might reach as much as 30 degrees lower.
This heat wasn’t quite as formidable as Tuesday’s, which set at least 50 heat records, with 21 sites sweltering in triple-digit temperatures. Around 127 million individuals remained under heat advisories from the National Weather Service, a slight reprieve from the prior day. Power suppliers worked tirelessly to meet the high demand for electricity, keeping spaces cool and illuminated.
Bob Oravec from the Weather Prediction Center commented, “It’s still going to be, I think, pretty bad across the East… today is probably the last day of widespread record potential. It might not be quite as hot as yesterday by a few degrees.” Highs in the upper 90s were anticipated across much of the East.
Warnings of “extreme heat” extended from North Carolina to New York, and as far west as West Virginia. Locations from New York to Richmond were expected to near triple-digit temperatures. Yet again, places like New York’s John F. Kennedy Airport, Newark, and Baltimore reported temperatures exceeding 100 degrees.
The unexpected warmth on Wednesday morning, due to northwesterly winds carrying heat from the previous day, caught many by surprise. Nantucket, Massachusetts, recorded temperatures over 90 degrees when only 82 was anticipated.
The steadily oppressive heat dome affecting the East was projected to dissipate. A cold front brought relief, sweeping down from New England, ready to cool the region significantly by the week’s close. Philadelphia, which hit an unprecedented 101 degrees on Tuesday, was set to see temperatures drop to the cooler low 70s by week’s end, according to Ray Martin of the National Weather Service.
“This is going to feel like a shock to the system,” mentioned Martin, but he noted it wasn’t unusual. Friday’s forecast for Boston predicted a 34-degree decline from Tuesday’s peak, dramatically shifting the feeling to another season entirely.
However, this cool respite is temporary. Slightly warmer-than-average temperatures are expected to follow, although not reaching the extremes experienced earlier in the week. Climate scientists point out that weather whiplash, shifting from one extreme to another, is increasing as global warming continues due to fossil fuel use.
Record-breaking heat was most brutal on Tuesday in Baltimore, reaching 105 degrees and breaking previous highs by four degrees. Nights offered little relief, with temperatures only dipping to 87 degrees. Coastal states from Maine to South Carolina saw locations hitting 100 degrees, with parts of Georgia and Florida reaching 99.
“With rising temperatures, the reliability and stability of systems are compromised,” noted Bernadette Woods Placky, Chief Meteorologist at Climate Central. Consequently, electricity demands surged. PJM Interconnection, the largest grid operator in the nation, reported peak demand since 2011, with only slight reductions later.
“We have an aging grid infrastructure in the United States, and this heat impacts it significantly,” explained Kate Guy, a senior research fellow at Columbia University’s Center on Global Energy Policy. Climatic changes are exerting unprecedented pressure on these systems due to rising demand and increasingly historic temperatures.
The extreme temperatures also caused infrastructure problems. In northern New Jersey, an interstate highway saw the pavement buckle in two locations. This prompted temporary lane closures while repairs were underway. Similarly, in Chicago, streets were closed for repairs after the high heat caused failings in the pavement.
The Illinois Department of Transportation mentioned that “Prolonged high temperatures can cause roads to expand, leading to buckling or blowouts,” affecting driving conditions. In Virginia, the heat caused a bridge in Chesapeake to malfunction, leaving it stuck open.