LANCASTER – Oppressive heat and humidity will be returning to our area. A heat advisory is in effect from noon today through 8 p.m. on Friday. Heat index values of 100 to 104 degrees are expected through the period. The hot temperatures and high humidity may cause heat related illnesses. Make sure that precautions are implemented such as drinking plenty of fluids like water and avoiding caffeinated drinks and alcohol, staying out of the sun and take frequent breaks if you must be outside, and staying in air-conditioned rooms and buildings.