Forecasts indicate heat indices will range from 107 to 112 degrees.
An Air Quality Alert also is in effect for several counties in the central part of the state, which will likely stay in effect through Saturday evening.
Warnings and advisories have been in place all week and Thursday's temperatures tied the record of 102.
On Saturday, Duke Energy was reporting as many as 8,000 customers in Durham and Wake Counties without power, while Progress Energy was reporting more than 7,000 without power in Raleigh.
Saturday's combination of heat and humidity from late morning through sunset will produce dangerously high heat indices, creating significant stress on individuals and increase the risk of heat related illnesses.
As expected when temperatures climb, officials are advising residents to stay indoors, but if you do have to go outside, limit activity to early morning or evening and drink lots of water. Also, don't forget about your pets, neighbors or relatives who may not have air conditioning.
If you work outside, wear lightweight, loose fitting clothes. The Occupational Safety and Health Administration suggests scheduling frequent rest breaks in shaded or air conditioned areas.
The NWS says little relief is expected overnight Saturday with heat indices remaining in the 80s.
Sunday is predicted to be the last day of triple digit heat. Cooler temperatures are expected next week with better chances for afternoon storms.