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.
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.
Another quiet day is on tap for Thursday with high pressure in control. Lows bottom out in the low 70s, warming to around 90° in the afternoon. Dry air (for this time of year, anyway) will hang on for one more day, though it will be a bit more humid than it was on Wednesday. High pressure and warm air aloft should keep a lid on thunderstorms for one more day as well.
Unsettled weather continues as the remnants of short-lived Tropical Storm Arthur move across GA and South Carolina late tonight into early Friday. From there, more typical summertime weather sets in.
We’re back in the 90s on Thursday as we get a brief lull in between disturbances, but showers and thunderstorms will return in the afternoon and evening as a slug of moisture from what we expect will be the remnants of Tropical Storm Arthur, which was christened earlier today, There will be a risk for a storm or two to produce some damaging wind gusts, but the overall severe weather threat this far to the east is fairly marginal. Will keep an eye out, though.
High pressure remains in control across the area, limiting afternoon thunderstorms and allowing heat to continue to build on Thursday. We’ll start in the mid-70s, warming to the mid-90s in the afternoon. Mix in dewpoints in the low-to-mid-70s and that will yield heat indices approaching or even slightly exceeding 100°. And while a brief popup sbower is never fully out of the question this time of year, the vast majority of us will stay rain-free.
High pressure at the surface and aloft will remain the primary weather driver for Friday and the weekend, with a bit more in the way of heat returning to the area starting Friday. Temperatures Friday start around 60°, warming to around 90° in the afternoon under mostly sunny skies. Dewpoints will remain generally in the 50s before the seabreeze pushes in a little more humid air from the Atlantic later in the day, but even then, they’ll only run in the low 60s with cooling temperatures behind them. It will be one of those rare days where the heat index may actually run slightly cooler than the actual air temperature, in fact, as the relatively dry air will allow sweat to do its thing.
Another comfortably warm day lies ahead for Thursday as high pressure at the surface and aloft remain the dominant weather features. Temperatures will once again start well on the cool side of normal for this time of year, bottoming out in the upper 50s away from the coast. We’ll warm to the mid-80s in the afternoon, but low-50s dewpoints will help not to make it feel terribly uncomfortable.
A cold front pushing southward overnight will stall out to our southwest, pushing some drier air into the area in the meantime and cooling things off a few degrees compared to the past few days. Friday still starts in the low 70s, but still a few degrees cooler than Thursday. Temperatures will head to the mid-80s in the afternoon with a few showers or storms possible midday, but otherwise, expect a quieter weather day compared to Thursday’s rambunctious thunderstorms which brought some much-needed rain to the Highway 17 corridor and points east.
Heat peaks Thursday before scattered to numerous showers and thunderstorms fire along the seabreeze in the afternoon. From there, a cold front sags southward across the area, and keeps shower and storm chances going through Thursday night. We’ll start the day on the warm side with lows in the mid-70s. More westerly winds will keep things a bit drier to start the day, but these winds will help enhance convergence along the seabreeze for those aforementioned showers and thunderstorms as we get into the afternoon. Before thunderstorms begin to disrupt the temperature curve, highs will peak in the low 90s, and heat indices will easily run in the mid-90s, perhaps getting closer to 100° than we’d like in the Highway 17 corridor.
Severe thunderstorms aren’t expected, but some gusty winds can’t be ruled out. There’s plenty of available moisture for a lot of rain to fall in a short period in a few spots, too, but not everyone will see a downpour. However, it seems probable that most of us should be able to measure precipitation by Friday morning.
