Heat and humidity continues for Friday and the weekend with high pressure aloft the main weather driver. Atlantic high pressure will continue to drive high dewpoints into the area, and that not only will drive heat indices well into the 100s, but it will keep us quite toasty at night, too. Expect lows in the upper 70s each day, perhaps not dropping below 80° closer to the coast and downtown.

High pressure rebuilding aloft will bring more sunshine — but more heat, too. We’ll start Thursday in the mid-70s inland to upper 70s near the coast. From there, plenty of sunshine will drive highs into the mid-90s. Dewpoints will be fairly juicy — generally in the mid-to-upper 70s — and this will drive heat indices well into the mid-100s. Closer to the coast as well as in downtown, dewpoints near 80° will help drive the heat index up toward 108° for at least a brief period. Heat Advisory criteria is a heat index 108°-112° for two hours or more, and we certainly could be close in the coastal corridor. Regardless, be sure you’re taking frequent breaks in the shade with plenty of water if you’re working outside.

The pattern turns a little more settled as high pressure builds back in aloft. As a result, we will see more sunshine as the week progresses, though with that will come warmer temperatures, too, which could push Heat Advisory thresholds in spots.

Showers and thunderstorms will feature prominently in the forecast on Tuesday as they develop around a stalled boundary lingering to the south. Periods of heavy rain will be possible, and an area or two of freshwater flooding can’t be totally ruled out. However, severe weather is unlikely, and this will largely be a beneficial rainfall event. Even better, highs should peak below 90° for the first time since June 24. So, even though there will be rain, it’ll be awfully nice to not be baking.

The main flooding concern arrives with the evening high tide; minor to moderate coastal flooding will be possible between 7-10 PM. We’ll need to monitor where the rain is carefully; any rain that coincides will cause issues downtown.

After a week of consecutive heat headlines, whether they be Heat Advisories or Extreme Heat Warnings, a front dropping in from the north — and the accompanying unsettled weather — will take the edge off the heat for at least a few days.

A slower frontal progression from the north will allow air temperatures to head back into the mid-to-upper 90s on Sunday, prompting another round of Heat Advisories and juicing up the atmosphere for another round of strong to potentially severe thunderstorms in the afternoon and evening.

After another 99° day at the airport, we’ll take one more run at the century mark on Saturday before a front drops toward the area on Sunday, bringing about more unsettled weather that will keep temperatures a little more in check.

Charleston International Airport hit 100° today. It’s the first century-mark temperature reading there since May 29, 2019. There will be a couple more opportunities to get back there before the pattern changes to something more unsettled and cooler late this weekend into next week.

It was a stifling hot Wednesday in the Lowcountry, with highs reaching the upper 90s and heat indices peaking between 113-116° in parts of the metro area. Another round of high heat is in store for Thursday, as temperatures once again return to the upper 90s. Dewpoints near the coast and behind the seabreeze should surge well into the mid-to-upper 70s once again, sending heat indices between 108-113° (with locally higher readings possible) in the Highway 17 corridor. This has prompted another Extreme Heat Warning for Charleston County as well as the southern portion of Berkeley County that includes Hanahan and Daniel Island. Elsewhere, a Heat Advisory will be in effect for heat indices around 108-110°. Model guidance still suggests a few showers and thunderstorms will fire off along and ahead of the seabreeze, which will help cool some of us off. Coastward storm motions moving against the inland-moving seabreeze could cause some back-building of thunderstorms with some locally heavy rain. The strongest storms could produce damaging wind gusts, and a warning or two can’t be totally ruled out as a result.

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.