The National Weather Service in Charleston issued another heat advisory for today, the 56th day of the year in which temperatures have exceeded 90 degrees.

Highs are expected to reach in the mid-90s with a heat index as high as 110. There's a slight chance of showers between 2 p.m. and 10 p.m. Lows are expected to fall to about 76 degrees tonight.

The National Weather Service has issued 28 heat advisories or excessive heat warnings for its coverage area dating back to June 13, according to Meteorologist Ryan Aylward.

The high temperatures combined with moderate humidity levels can create conditions that lead to heat-related illnesses. Residents are urged to stay out of the sun as much as possible, drink plenty of fluids, and check on the elderly.

Another advisory is likely Thursday as temperatures are expected to remain in the mid-90s for the rest of the week.

"There's pretty much not an end in sight," Aylward said.