Multiday warnings of extreme heat were imposed by federal officials in New York City, Philadelphia, Boston, Washington, and other cities ahead of Fourth of July celebrations as temperatures neared or surpassed 100 degrees Fahrenheit combined with high humidity on Thursday.
“A strong upper-level ridge will remain anchored across the central and eastern U.S. through the weekend, supporting a [prolonged] and dangerous heatwave from the Midwest into the Ohio Valley, Mid-Atlantic, and Northeast,” said the National Weather Service (NWS) in a bulletin issued Thursday.
Widespread highs in mid 90s to low to mid 100s Fahrenheit, combined with relatively high dew points, will produce “heat indices between 100-115 degrees” on Thursday, the service said. Some areas will see daily temperature records as warm overnight low temperatures in the 70s or even 80s are possible….