(Reuters) - A unrelenting heat wave on Thursday was expected to scorch the U.S. East Coast and South for the third day as dangerously high temperatures had forecasters warning about the dangers of dehydration and exposure.
Heat warnings and advisories were in effect from South Carolina up into parts of New England as heat index values were expected to reach 110 degrees Fahrenheit (41 C) in Washington D.C. and near 100 degrees in New York City on Thursday, the National Weather Service (NWS) said.
The U.S. heat wave follows conditions in Europe this week that have touched off wildfires and set record temperatures in the kind of weather event that scientists say will become more frequent with climate change.
The NWS and local officials urged people to stay indoors, avoid strenuous activities and stay hydrated.
"To reduce risk during outdoor work ... schedule frequent rest breaks in shaded or air conditioned environments," the NWS said. "Anyone overcome by heat should be moved to a cool and shaded location."
The heat was expect to stifle the East Coast through the weekend as daily highs were forecast to remain in the 100s across the region, the NWS said.
Several cities issued heat emergencies and opened cooling centers in public buildings and urged people to take advantage of public pools.
The continued heat wave also was to stretch from Eastern Texas through Louisiana and Arkansas and into Central Alabama, where the temperature could soar above 110 degrees on Thursday afternoon, the NWS said.
"Overnight lows are likely to remain in the 80s in many spots, providing little nighttime relief," the service said.
Earlier this week, several spots in the South saw record daily temperatures, including Wichita Falls, Texas where a high of 115 degrees was recorded on Tuesday.
(Reporting by Brendan O'Brien in Chicago, Editing by William Maclean)