Sticky heat was expected to smother much of the country's midsection in coming days as hotter than usual temperatures continued to roast parts of the Midwest and South, forecasters said on Sunday.
Areas of Kansas, Missouri and Oklahoma were under excessive heat warnings with heat advisories issued for a large swath of the Central United States, according to the National Weather Service.
Heat and humidity were forecast to continue with air temperatures and heat index readings climbing well into the triple digits for parts of the region at least through midweek.
"It's pretty incredible to just be locked into a pattern of this kind of dry heat for this long for the Southern Plains," said AccuWeather.com senior meteorologist Dan Pydynowski.
"There doesn't seem to be any relief in sight," he said.
Dallas, for example, has reached or topped 100 degrees for nearly all of July.
"Yes, they are used to the heat, but to have this many days in a row of triple digit heat is extreme even for a hot place like Dallas," Pydynowski said.
The unrelenting stretch of hot, dry weather in Texas has sent an increasing number of people to emergency rooms for heat illness.
San Antonio paramedic Christopher Velasquez said too many people in Texas think they can handle the heat, and find out the hard way they can't.
And just a day after Tropical Storm Don failed to produce much needed precipitation over the rain-starved state, the next tropical system was developing in the Atlantic.
"All indications are that this will become Tropical Storm Emily at some point in the next day or two," said Pydynowski.
It remains too early to tell if the storm's projected path will move toward the United States, he said.
In parts of Minnesota and the Dakotas on Sunday severe thunderstorms could stir up high winds, hail and the potential for a tornado to develop, according to AccuWeather.com.
In New England, beachgoers were flocking to the shore to soak up sunny weather on Sunday. The Northeast was expected to be seasonably warm, but not endure extreme heat.