No surprise here, but the National Weather Service has made it official: A heat advisory is in effect for Friday, from 11 a.m. to 9 p.m., for the entire metro region. High temperatures from the upper 90s to low 100s will produce heat index values of 105 to 109.

A heat advisory is not as extreme as an excessive heat warning, which was in effect last Friday, when heat indices exceeded 110. But tomorrow’s combination of heat and humidity could still produce heat-related illnesses or worse, so take it easy, drink plenty of fluids, and cool off in air-conditioned environments.

Check out today’s Weather Gang lab below where I discuss the heat as well as tropical storm Don:

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Sweat Ceiling, the sequel: Details on coming extreme heat and humidity

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