This type of condition also makes it hard for our sweat to evaporate, which is a natural cooling process. That's why it's so important to get our bodies into the air conditioning, because even overnight weather conditions will be warm.
How high will the heat index get?
The heat index should climb to 95-99 on Thursday and Friday. By the time we get into the weekend, the afternoon heat index will range from 100-105. Add a mostly sunny sky, and it's just going to be sweltering outside.
How long should this last?
We are looking at seven or more days of oppressive heat and humidity. When looking at a few long-range weather models, I'm easily seeing highs above 90 through the Fourth of July.