Nearly 200 million people in US are under heat, flood advisories

Nearly 200 million people in the United States, or 60% of the US population, are under heat warnings or flood warnings, or watch as high temperatures spread and new areas are announced for hurricanes. big.
The National Weather Service said a “dangerous” heatwave began to scorch the Northeast and mid-Atlantic on Thursday and will continue through the weekend. Severe thunderstorms and flash floods are possible in parts of the Northeast and South, New England and South Florida. Meanwhile, the string of record-breaking temperatures will span the Southwest and Midwest.
“It (hits) all the major cities,” said Bob Oravec, principal forecaster for the National Weather Service’s Weather Prediction Center. “That’s why the (affected) population is so high.”
Scientists have long warned that climate change, caused by the burning of fossil fuels, will lead to more extreme and prolonged weather spells.
Predictions for extreme temperatures continue to come a day after the World Meteorological Organization and the European Union’s Copernicus Climate Change Agency declared July 2023 the hottest month on record.
On Thursday, the heat and humidity in major cities along the East Coast, including Washington, D.C., Philadelphia and New York City, produced a real sensation of over 100 degrees Fahrenheit (37.8 degrees Celsius) . Weather forecasters expect some records to be broken on Friday with temperatures 10 to 15 degrees Fahrenheit (5.5 to 8 degrees Celsius) above average.
In New England, communities are bracing for a “double threat,” as Oravec calls it, extreme heat and flash flooding.
“You can have very high temperatures for a good part of the day and then have strong thunderstorms that produce heavy rain and then possibly flood,” he said.
The Southwest and the South continued to experience record heat. There, sweltering heat enveloped the area for weeks. One New Mexico-based meteorologist called the period of temperatures lasting above 100 degrees (37.8 C) unprecedented.
“They probably won’t have much sympathy for the rest of the country,” Oravec said.
Due to extreme heat, two of the nation’s largest power grids are under strain, which could affect Americans’ ability to cool.
The country’s largest grid, PJM Interconnection, declared a level one energy emergency warning for its 13-state grid on Wednesday, meaning the company is concerned about its ability to provide enough electricity.
“PJM currently has enough power to meet forecast demand, but operators continue to monitor grid conditions for any changes,” said Jeffrey Shields, a company spokesman.
PJM is not the only grid to issue such warnings. Independent system operator Midcontinent, which mainly includes states in the Midwest and Northern Plains, issued a similar warning on Thursday.
The California Independent Systems operator also issued an emergency energy warning Wednesday night, in part due to extreme temperatures in Southern California, but the warning expired the same day. Anne Gonzales, a spokeswoman for CAISO, said they hope to be able to meet demand in the next few days.
And a spokesman for the Electrical Reliability Council of Texas, which includes most of Texas, said they expect their grids to be up and running during this latest wave of severe weather across the country.
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Follow Drew Costley on Twitter: @drewcostley.
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