The high heat of the past couple days — we hit 98° again on Wednesday, just one degree off the record high — will let up on Thursday as high pressure aloft continues to weaken. Don’t misunderstand: it’ll still be plenty hot, but not to the Advisory-level thresholds we’ve hit recently. After a start in the mid-70s, likely in the wake of thunderstorms that are expected late tonight into early Thursday morning, temperatures in the afternoon warm to the low 90s. Dewpoints will mix down to around 70°, so heat indices should stay relatively tame, with a brief spike into the upper 90s possible as the seabreeze pushes inland. A few showers and thunderstorms could pop on the seabreeze, as is often the case this time of year, but nothing out-of-bounds is expected.
A very hot Tuesday is in the offing as high pressure at the surface and aloft remain in place, allowing temperatures to head into the upper 90s to around 100° across the area away from the coast, where temperatures should peak in the low to mid-90s. Regardless of where you are, heat indices should peak around 108-109° as well, prompting a Heat Advisory for the Tri-County area — the first of 2025 — that’ll go from 1-8 PM. If you are working outdoors during that period in particular, be sure you’re getting plenty of fluids and taking frequent breaks in the shade or, preferably, an air-conditioned environment. Be very vigilant about any children or pets in the car, too — it doesn’t take very long at all for temperatures to become very dangerous in cars, and we don’t want any hot car deaths. Look before you lock!
If a high of 100° verifies at the airport, it would be the first time since May 29, 2019 (the Before Times!) that the temperature at the airport reached 100° or higher. Triple-digit heat isn’t expected east of 17, including in downtown Charleston and at the beaches, but the closer proximity to higher-dewpoint maritime air will still send heat indices into the danger zone despite the lower air temperatures.
Looking for thunderstorms to cool you off? I wouldn’t count on it, though a stray storm can never be fully ruled out this time of year.
More heat and humidity are on tap for Thursday, but with a slightly better chance of storms in the afternoon especially as a front gets closer to the area. We’ll start the day in the mid-70s once again, warming back to the mid-90s in the afternoon. We’ll be keeping an eye on a line of thunderstorms to our northwest, which could help induce some stronger storms in the metro later in the afternoon through the evening hours. Damaging wind gusts would be the primary concern in the strongest storms, though the risk for severe weather is generally low (but not zero) across the area.
High pressure will continue to build in aloft, sending temperatures upward and storm chances downward. Tuesday will be another rather warm day, with lows in the mid-70s to start the day warming to the low 90s in the afternoon. Mix in dewpoints running in the low 70s, and that’ll yield heat indices right around the 100-101° mark during the height of the afternoon. Heat indices could even briefly spike in the immediate wake of the seabreeze as dewpoints surge before temperatures start to fall.
A storm or two will be possible along and ahead of the seabreeze, but with the capped atmosphere, it’s going to be tough to get much, if anything, to break through, much less sustain itself. Still, though, you can never completely rule it out this time of year.
After a quiet start to the day, another round of afternoon showers and thunderstorms are expected to develop and move across parts of the Tri-County on Thursday as we remain in an unsettled pattern. Alas, we will keep this going into the weekend, too.
Showers and storms, a few of which could be on the strong side, will be possible again on Tuesday, particularly in the afternoon, as low pressure aloft remains in place and the heating of the day kicks in. The warm and muggy airmass stays in place, with lows in the low 70s warming to the upper 80s in the afternoon before storms develop. Guidance suggests showers and storms develop in the 2-3 PM timeframe, and there will be the risk for a storm or two to become severe once again with damaging winds the main threat. The risk for severe weather is a little lower Tuesday, but will still need to be monitored especially after a rough day for Summerville.
Thunderstorms remain likely, especially in the afternoon, as low pressure lifts north and away from the area throughout the day. A warm and humid airmass remains in place, and this will get us off to a balmy start in the low 70s. Scattered to numerous showers and thunderstorms should redevelop by afternoon, keeping highs suppressed to the mid-80s. Rain could still be heavy at times, with spots potentially reaching another inch of rain or so before it’s over. Not everyone will see that kind of rain, though.
Breezy conditions remain possible especially at the coast and over the waters, so it’ll be another day where boating and beaching will be generally unadvisable. The good news, though, is that with the low pushing inland, the risk for any sort of tropical development — low as the risk was this entire time — has ended. (Take the wins where you get them.)
We’ve got one more day of quiet weather in store for Tuesday before low pressure offshore begins to send moisture back our direction starting Wednesday. Temperatures Tuesday start in the mid-60s, and we’ll warm to the mid-to-upper 80s under generally partly cloudy skies as high pressure builds in briefly from the north.
After a balmy start in the low 70s that could feature some patches of fog, temperatures will warm to near 90° in the afternoon before scattered to numerous showers and thunderstorms kick off courtesy of the seabreeze as well as some energy aloft. Heavy rain will be possible with these thunderstorms, and a few stronger storms with strong winds will be possible as well, with some of the high-res models pointing to clusters of storms developing and moving from southwest to northeast across the Lowcountry late in the day. Stay alert for rapidly changing conditions, particularly during the evening commute.
A reprieve from the early-season stretch of 90° temperatures commences Thursday in the wake of a cold front. We’ll start the day noticeably cooler and drier than previous days, with lows bottoming out in the mid-60s as opposed to the low 70s. Highs will still run a little warmer than normal, but upper 80s will still represent cooler highs, especially on the heels of highs in the low 90s the past few days. Despite the warmer-than-normal temperatures, the lower dewpoints in the mid-50s will send relative humidity values down to around 30% or so during the day, so at least any sweat will have a chance to do its thing to cool you off.
