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Temperatures will rise to high 80s and low 90s over the next few days. Potentially dangerous heat indices will likely occur, according to the National Weather Service.

There are currently no excessive heat warnings or advisories in place, but some may be issued in the coming days, the MWS said in a statement.

Highest heat indices will occur across the central and southern valley area; including Morristown, Greeneville and Tazwell.

Although temperatures will rise to 93 degrees on Friday, Heat indices will approach and possibly exceed 110 degrees across the southern valley.

The National Weather Service encourages those who will be out in the heat to stay hydrated and drink lots of water, apply sunscreen regularly when outdoors, dress in light colored and lightweight clothing, take frequent breaks in the shade or in an air conditioned environment.

Young children and the elderly may be more vulnerable to heat related illnesses. The NWS encourages everyone to take precautions.

The American Red Cross listed the signs of Heat Exhaustion and Heat Stroke.

Heat Exhaustion: heavy sweating; cold, pale and clammy skin; fast, weak pulse; nausea or vomiting; muscle cramps; tiredness or weakness; dizziness-headache-passing out.

Heat Stroke: high body temperature (104°F or higher); hot, red, dry or damp skin; fast, strong pulse; headache-dizziness; nausea-confusion-passing out.

Heat Dome

The Associated Press is reporting that scorching temperatures brought on by a “heat dome” have taxed the Texas power grid and threaten to bring record highs to the state before they are expected to expand to other parts of the U.S. during the coming week, putting even more people at risk.

“Going forward, that heat is going to expand … north to Kansas City and the entire state of Oklahoma, into the Mississippi Valley … to the far western Florida Panhandle and parts of western Alabama,” while remaining over Texas, said Bob Oravec, lead forecaster with the National Weather Service.

Record high temperatures around 110 degrees Fahrenheit (43 degrees Celsius) are forecast in parts of western Texas on Monday, and relief is not expected before the Fourth of July holiday, Oravec said.

WHAT IS A HEAT DOME?

A heat dome occurs when stationary high pressure with warm air combines with warmer than usual air in the Gulf of Mexico and heat from the sun that is nearly directly overhead, Texas State Climatologist John Nielsen-Gammon said.

“By the time we get into the middle of summer, it’s hard to get the hot air aloft,” said Nielsen-Gammon, a professor at Texas A&M’s College of Atmospheric Sciences. “If it’s going to happen, this is the time of year it will.”

Nielsen-Gammon said July and August don’t have as much sunlight because the sun is retreating from the summer solstice, which was Wednesday.

“One thing that is a little unusual about this heat wave is we had a fairly wet April and May, and usually that extra moisture serves as an air conditioner,” Nielsen-Gammon said. ”But the air aloft is so hot that it wasn’t able to prevent the heat wave from occurring and, in fact, added a bit to the humidity.”

High heat continued for a second week after it prompted Texas’ power grid operator, the Electric Reliability Council of Texas, to ask residents last week to voluntarily cut back on power usage because of anticipated record demand on the system.

-The Associated Press contributed to this report.