By Jason Samenow - NOAA has upped its peak heat index prediction for D.C. Friday to a stunning, sweltering 116 degrees. Remarkably, it predicts there is a 90 percent chance it will reach at least 110 and a 100 percent chance of at least 105. Earlier today, NOAA was predicting a maximum heat index of 109 Friday. And poor Richmond, Va.! NOAA projects its heat index will soar to a stifling 118 degrees.

http://www.washingtonpost.com/blogs/capital-weather-gang/post/shock-forecast-noaa-predicts-heat-index-of-116-in-washington-dc-friday/2011/07/19/gIQAB3kWOI_blog.html