HEAT DOME EXPECTED TO BAKE THE UNITED STATES
As we descend into the depths of summer, some of the year's hottest temperatures may be soon upon us. Forecasters expect a high pressure ridge and extreme temperatures to combine to create what is referred to as a "heat dome" over large portions of the United States.
A heat dome occurs when high pressure in the upper atmosphere acts as a lid, preventing hot air from escaping. The air is forced to sink back to the surface, warming even further on the way. This phenomenon will result in dangerously hot temperatures that will envelop the nation throughout the week. Heat index values for parts of the U.S. are expected to reach 110 degrees or higher. In response, the National Weather Service has issued heat alerts for more than a dozen states across the U.S.
This map, based on data from NOAA's HRRR Model shows the predicted high temperatures on July 18, 2016 at 5 p.m. EDT. These temperatures reflect the beginning of the scorching heat wave that is expected to last throughout the week.
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