What Is A 'Heat Dome' And Why Is It Causing The Tri-State To Swelter?
by Justin Lewis, CBS2 Meteorologist
A heat dome is a considerably large geographic area under the influence of high pressure in which excessively hot and humid conditions persist.
A pattern sets up where hot air at the surface rises into the atmosphere, returns to the surface due to the high pressure - and the process repeats.
Since the hot air can't escape -- it's as if there's a lid in the atmosphere -- it is referred to as a heat dome.
LINK: Tips To Beat The Heat: Your Guide To Summer Safety
A simple pattern change usually breaks down a heat dome, such as the passage of a cold front, and, furthermore, replaces the hot air mass with a relatively cool one.
An Excessive Heat WATCH means Be Prepared.
— National Weather Service (@NWS) August 12, 2021
An Excessive Heat WARNING means Take Action!https://t.co/u6mRz1mO1W pic.twitter.com/VpTPuZumFw
This is the scenario we're anticipating over the weekend into early next week where temperatures will return to near normal.