About 65 million people were under a heat warning in the northeastern and midwestern states on Friday, as an early-season heat wave in the US continued to toast the region.
Record temperatures were achieved in some areas, with heat indexes combining temperature and humidity reaching 100F and 110F. Calendar day highs were broken in Maine, New Hampshire and Pennsylvania.
The National Weather Service warned that people without reliable air conditioning would be hardest hit. Across the Ohio River valley, the heat risk index was at level 4 – labeled “extreme” – for the next two days.
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“This rare and/or prolonged extreme heat with little to no nighttime relief affects anyone without effective cooling and/or adequate hydration,” the agency said, adding that it is likely to “affect most healthcare systems, heat-sensitive industries and sectors.” infrastructure”.
With temperatures dropping only slightly at night, the national forecaster advised people to “drink plenty of fluids, stay in an air-conditioned room, stay out of the sun and check on relatives and neighbors.”
The sudden intensity of summer heat in the region has been attributed to the northward movement of a high-pressure heat dome that had established itself over Mexico and the southwestern US in March.
He slowly moved north, breaking temperature records along the way. The climate group World Weather Attribution released a report on Thursday saying the southern heatwave at the end of May was 35 times more likely to be due to climate change, and was 2.5 degrees hotter.
In Texas, Governor Greg Abbott issued a disaster declaration for 51 Texas counties after Tropical Storm Alberto swamped parts of the state. New Mexico has also requested federal assistance after wildfires forced the evacuation of a city in the southern part of the state.
But forecasters have predicted that colder air with lower humidity will move across the Northern Plains and upper Midwest this weekend, and into the Northeast soon after.
Still, it will be uncomfortable in some regions until then. Temperatures are expected to soar into the 100s in the mid-Atlantic states “with record temperatures possible.”
The heat has caused infrastructure problems. In New York, hundreds of commuters were stranded on trains leaving Penn Station when a power outage and a wildfire in New Jersey’s Secaucus swamp area disrupted service.
US train operator Amtrak said its trains would have to run at lower speeds because of the heat.
