More than 40% of Americans are at risk of extreme heat today

A brutal heat wave is set to persist Thursday as more than 140 million Americans from coast-to-coast are under heat alerts, with parts of the Northeast expected to sizzle under their highest temperatures this year.

Dangerously high temperatures are creeping east into parts of the Midwest and Northeast over the next two days after extreme heat consistently smashed record highs in southern states in recent weeks.

“Low temperatures will range mostly from 75 to 80, with lower 70s in the far outlying suburbs. Coupled with elevated humidity this will make for uncomfortable conditions at night,” especially in New York City and northeast New Jersey, forecasters at National Weather Service in New York City said.

The looming threats have triggered officials to take a series of preventive steps aimed at reducing the harmful impacts of extreme heat, which kills more people than any other irregular weather event in the US.

Heat indices – a measurement of what the temperature feels like when accounting for relative humidity – are expected to top 100 degrees Fahrenheit across many areas in the Northeast and the Midwest.

Here’s how some places are bracing for potentially record high temperatures:

New York City: Nearly nine million residents across the nation’s largest city are under an excessive heat warning Thursday beginning 11 a.m. through 9 p.m. Friday. Temperatures are forecast to soar to nearly 100 degrees Fahrenheit, and the air will feel as high as 105 degrees. Thursday and Friday are expected to bring the highest temperatures seen in New York City this year.
Washington, DC: The nation’s capital is under an excessive heat watch as temperatures are expected to be nearly 100 degrees. But they will feel much hotter: Thursday may feel as high as 104 degrees while the “feels like” temperature could reach as high as 107 degrees Friday.
Baltimore: The Charm City in Maryland has activated the season’s first Code Red Extreme Heat Alert beginning Thursday through Saturday, according to a city news release. The declaration signals the city plans to open several cooling centers as temperatures in the region could feel higher than 100 degrees.
Connecticut: Gov. Ned Lamont activated the state’s extreme hot weather protocol, which is in effect through the weekend. Cooling centers across the state will be available, with the governor’s office warning that temperatures could feel between 95 to 105 degrees. Lingering impacts are expected to persist during the overnight hours, particularly in urban areas throughout the state, according to a news release.
Missouri: Heat indices across St. Louis and Kansas City will top 100 degrees Thursday and Friday, according to the National Weather Service. Temperatures could reach the low 100s in both cities, where heat advisories are in effect.
Minnesota: The Twin Cities are under an excessive heat warning Thursday, when heat indices are expected to hit 100 degrees. “Little cooling relief is expected tonight as temperatures remain in the 70s overnight,” the NWS in the Twin Cities said.
Indiana: The capital city of Indianapolis will see temperatures between 95 and 99 degrees Thursday and Friday, respectively. The heat index could be as high as 105 degrees Thursday.

As temperatures spike, PJM Interconnection – the nation’s largest power grid system – has declared an emergency alert. The move activates all systems to be online, including those with planned outages.

PJM coordinates electricity for more than 65 million people in all or parts of Delaware, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia and Washington, DC, according to its website.

President Joe Biden is expected to announce actions to combat extreme heat in a briefing Thursday morning as the dangerous heat wave expands across the US.

Extreme heat from coast-to-coast

The oppressive temperatures have put entire states under heat alerts.

Missouri, Iowa, Indiana in the Midwest are all under heat advisories while New Jersey is seeing a combination of heat advisories and excessive heat warnings, according to the NWS. Most of Illinois, Nebraska, Kansas and Oklahoma are also under heat advisories.

Heat alerts are also in effect for parts of Southern California and Arizona.

In the south, heat indices continued to break records Wednesday.

On Wednesday afternoon, Miami hit a heat index of 102 degrees, marking the city’s 46th consecutive day with the heat index exceeding 100.

El Paso hit a high temperature of about 107 degrees on Wednesday, which continues their streak of consecutive days of high temperatures over 100 to 41 days. The city is expected to exceed 100 degrees – again – on Thursday.

Phoenix reached 118 degrees, extending its streak to 27 consecutive days with a high temperature exceeding 110. The city also saw 17 consecutive days of low temperatures above 90 degrees.

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