The weather story of this Fourth of July holiday looks to be the first big heat episode of the season across the Lowcountry. After highs in the low 90s on Saturday, air temperatures should top out in the mid-90s on Sunday, with heat indices running above 105° in the afternoon thanks to dewpoints in the low 70s. There will be a chance for an isolated shower or thunderstorm or two on the inland-advancing seabreeze in the afternoon, but the vast majority of us will stay rain-free — and hot.

The heat really begins to turn up heading into Monday and Tuesday. Air temperatures top out at 97° on Monday and 95° on Tuesday, but the continued influx of humid air will cause heat indices to meet or exceed 110°, which is heat advisory criteria for July 1 and beyond. Generally, when heat indices head north of 105°, the risk for heat stroke begins to increase, making this round of heat particularly dangerous if you’re not getting enough water and are outdoors over the next few afternoons.

This increased moisture will also help drive higher afternoon thunderstorm chances Monday and Tuesday, with maybe even an isolated severe storm on Tuesday. Regardless of severity, all thunderstorms are dangerous due to the lightning they produce. When thunder roars, go indoors!

Coastal flooding concerns continue each evening

Coastal flooding remains a concern with the evening high tides as we head into next week, with minor to moderate flooding possible. We scraped minor flood stage on Saturday evening as expected, and expect to see somewhat higher water levels for Sunday and beyond as the full moon arrives. The Sunday evening high tide at 8:03 PM should top out around 7.2-7.4′, which will be enough to close a few roads in downtown Charleston. Expect similar flooding Monday and Tuesday evenings as well, though high tide will get progressively later (8:58 PM Monday, 9:53 PM Tuesday). Keep an ear out for possible Coastal Flood Advisories from the National Weather Service.

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