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KNOXVILLE, Tenn. - Parts of the Midwest and South will continue to bake Thursday as a heat wave that eased up a bit over the weekend returned with a vengeance.
The regional toll over the last two weeks has grown to at least 50, with one new death reported in Missouri and two in Alabama on Wednesday.
Sweltering heat was also expected to make life even more miserable in Ohio, where heavy rains have flooded towns and forced residents from their homes. The National Weather Service said temperatures are expected in the upper 90s in parts of Ohio, with heat indexes as high as 104.
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In Kentucky, a fire at a power substation Wednesday forced the nation's largest public utility to ask major industrial customers to reduce their electricity use as a heat wave continued to dog the region it serves.
The fire caused a partial shutdown at a Tennessee Valley Authority plant as temperatures were predicted to rise near 100 degrees through Friday in the Knoxville-based utility's seven-state territory.
12 days of 100+
In Nashville, Tuesday marked the 12th day of 100 degrees or above this month, the most recorded in any month for the city. Nashville set a daily record of 102 on Wednesday, while Memphis matched a 2000 record of 100.
Gov. Phil Bredesen announced Wednesday that the state will dip into emergency funds to reimburse community service agencies that buy air conditioners for low-income people suffering from the heat.
"We've contacted them today to say money is no object — if someone needs an air conditioner, we have emergency funds for those purposes," Bredesen said.
The heat wave has forced some schools to hold classes for only half a day and is renewing interest in a school calendar that delays the return to classes until after Labor Day, when the weather is usually cooler.
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Power plant fire
The blaze at the power plant was extinguished without injuries but knocked out a high-voltage transmission line to the Paradise plant near Drakesboro, Ky. The TVA had to shut down one of three 1,000-megawatt units at Paradise until the substation can be fixed, officials said.
An instrument transformer that measures the flow of power on transmission lines caught fire, the utility said.
"Extreme heat across the Tennessee Valley and heavy power loads on TVA transmission lines contributed to the device failure," spokesman John Moulton said.
For the first time since the heat wave began, the utility asked 25 major industrial customers that receive power directly from it for voluntary cutbacks. Utility officials said those efforts were paying off, saving about 120 megawatts.
The TVA also appealed to its 158 power distributors to turn up thermostats, turn off unnecessary lights and unplug unneeded electrical equipment in their offices. The utility adopted the move in its own buildings two weeks ago.
The agency set an all-time high of 33,499 megawatts on Aug. 16. TVA provides electricity to about 8.7 million consumers across Tennessee and to parts of Kentucky, Alabama, Mississippi, Georgia, North Carolina and Virginia.
A thousand megawatts would power about 550,000 homes in the utility's coverage area.
Copyright 2007 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
Record-high temperatures are being reported across parts of the Midwest and Southern United States. However, the extreme heat has turned deadly for many. Over 50 deaths are being blamed on the heat, with the latest deaths coming from Alabama and Missouri.

In Kentucky, a fire broke out at an electricity substation, forcing the Tennessee Valley Authority to request major electrical consumers to reduce their power use. 

In Nashville, yesterday's high temperature reached 102ºF. Nashville has seen 13 days this month where the high temperature reached above 100ºF.

The extreme heat wave is now expected to move into Ohio, a state where very heavy rainfall caused evacuations and considerable structural damage. The National Weather Service predicts heat indexes to soar as high as 104 degrees.