Dangerous heat and humidity continues across the Lowcountry as we get into the second half of the work week with fewer opportunities for relief from thunderstorms.

Heat and humidity will be particularly nasty on Wednesday, as ridging builds in aloft and air temperatures respond by heading into the upper 90s. Dewpoints in the low to mid-70s will help drive heat indices perhaps in excess of 112° near the coast, with heat indices running 108°+ further inland. This has prompted an Extreme Heat Watch for Berkeley and Charleston counties, while a Heat Advisory will be in effect for Dorchester County from 11am-7pm. Heat safety will be paramount, as the risk for illness and heat stroke will be elevated. If you’ll be outside during the height of the day, get plenty of shade and/or AC, and make sure you’re drinking plenty of water.

High pressure building in aloft will help tamp down on the coverage of showers and thunderstorms in the afternoons starting Wednesday. While a few storms should still form along and ahead of the seabreeze, they’ll be fewer and far between as the week goes on, limiting the relief that any thunderstorm may be able to impart. As is common this time of year, there is always an outside risk for a storm to produce damaging wind gusts, but widespread severe weather is not expected.

While dewpoints will mix out a little more Thursday and Friday, heat indices will still run well into the 100s, perhaps approaching 108° in the wake of the seabreeze where dewpoints will surge into the mid-to-upper 70s before air temperatures cool off some. More Heat Advisories seem plausible, but we’ll see how the details ultimately work out. More concerning will be the duration of the heat wave and the lack of recovery we’re getting overnight, with lows in the upper 70s away from the coast each day. It’s worse for Downtown and at the beaches, where temperatures may not fall below 80° for several more days. Cumulative heat stress can become quite a health issue. Be sure to check on the elderly and other vulnerable people in your lives to make sure they’re okay.

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