WASHINGTON (Reuters) - Fiery reds and oranges nearly covered the United States on meteorologist maps as a massive heat wave hit hard in much of the country on Saturday.
Temperatures averaged up to 15 degrees above normal, with most peaks in the 90s but triple digit heat expected to strike from Montana to New Mexico, according to lead meteorologists for The Weather Channel and The National Weather Service.
Paired with oppressive humidity, temperatures will feel even hotter, as measured by the heat indexes.
The NWS issued excessive heat warnings and watches for the Midwest from Texas to Canada, and heat index values over 110 degrees Fahrenheit (43 C) are possible for portions of the central and eastern United States by the middle of next week.
Locations affected are expected to see temperatures and heat indexes of up to 117 degrees (47 C), including cities like Minneapolis where that is extremely rare.
"The stage is being set for a massive heat wave to develop," the National Weather service warned on Thursday.
"When your body temperatures rises on a hot day, as much as two liters of sweat can pour out of ... sweat glands each hour," said Weather Channel Senior Meteorologist Jonathan Erdman, meaning your body has a harder time keeping cool.
Meteorologists predict the heat wave will hang on through as late as Friday of next week. Following record heat that has already blasted the country from early June, the prolonged high temperatures pose special dangers to children and the elderly and economic pain to farmers and ranchers.
While the year is entering its hottest time -- the latter half of July -- an exceptional drought is exacerbating summer heat that has broken daily, monthly and all-time record highs over the last couple of months.
The U.S. Department of Agriculture said on Friday that drought and wildfires through spring and early summer have affected millions of acres of cropland, forests and grasslands across the United States.
In a statement directed to farmers and ranchers in states affected by extreme weather, the USDA said drought conditions stretch from Arizona to the southern Atlantic states.
In Colorado, the NWS forecasts temperatures to soar near triple digits in the northern part of the state over the weekend, after 10 straight days of monsoon rains.
The southern part of the state did not see the rains, and it remains in the grips of a multiyear drought that prompted Colorado Governor John Hickenlooper this week to request federal drought assistance in eight counties.
Most of Utah is expected to see temperatures in the 90s over the weekend, according to the NWS, which also issued a red-flag warning for extreme wildfire conditions in the southwest and central parts of the state.
Several deaths in Tennessee, large swathes of which are rural and poor, have been attributed to the prolonged heat wave -- in a few cases, due to a lack of proper air conditioning.
Memphis Light Gas and Water began an emergency reconnection program Friday for people who had been cut off for lack of payment, letting them reconnect to the electricity that powers cooling systems for one price, no matter how much they owe.
Next week the massive high pressure ridge suppressing storm and cold fronts is expected to move from the central United States to the east, spreading increasing heat to the Mississippi and Ohio regions and East Coast.
(Additional reporting by Tim Ghianni in Nashville and Keith Coffman in Denver; Editing by Jerry Norton and Todd Eastham)
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