Jared Smith founded @chswx on Twitter in 2008 as an experiment in disseminating weather data through social media. In the ensuing decade-and-a-half, @chswx has provided live coverage of tropical cyclones, tornadoes, severe weather, and even a couple bouts of winter weather to the good people of Charleston, SC.
The final week of August will end on a warm and more humid note than the past 7-10 days have offered across the area. Storms will take a pause, though, as high pressure aloft puts a lid on widespread cloud cover, much less thunderstorm development, for much of the week.
The stationary front that’s kept shower chances in the neighborhood over the weekend still lingers nearby, and a shower or two will be possible (though unlikely) on Monday. Dewpoints will continue their steady climb, peaking in the mid-70s, which will make the upper 80s feel more like the mid-90s.
High pressure aloft will become more entrenched across the area starting Tuesday, setting us up for a rain-free stretch through Friday that will feature warmer-than-normal temperatures for late August. We should see highs peak in the low-to-mid-90s each afternoon, and with dewpoints peaking in the mid-70s, heat indices should head back into the 100s especially Wednesday-Friday. We’ll fall short of the Heat Advisory threshold of 108°, but it’ll still be plenty warm with just a few clouds to hide the sun from time to time. The high pressure pattern will keep winds generally light, too, so there won’t be much of a breeze, either.
As we head into Labor Day weekend, the high pressure ridge aloft gets shunted south and west as a trough digs in a bit to our north. This will kick up the chance for a few afternoon thunderstorms and take some of the bite out of the heat, but it’ll still be plenty warm as we bid farewell to summer as meteorological fall begins on Sunday.
Cool high pressure will hang tough over much of the Carolinas heading into the weekend, though coastal areas could run a little warmer and more humid depending on the position of a stationary front/coastal trough nearby. The trough keeps cloud cover in the forecast for Saturday in particular, and that combined with northeasterly winds will keep temperatures down into the mid-80s in the afternoon after another mid-60s start. A stray shower or thunderstorm will be possible Saturday, particularly closest to the coast, with the nearby trough. A little more humidity creeps into the area for Sunday as winds just off the deck turn more onshore. It remains to be seen just how deep the moisture becomes with some fairly serious differences in model guidance showing up, but ultimately be ready for an isolated storm or two Sunday afternoon. We will see dewpoints return to the low 70s; as high temperatures head to the mid-to-upper 80s, that will yield heat indices in the low 90s. Nothing terribly heinous, though certainly not as comfortable as it has been.
While northeasterly winds continue around the high pressure wedge, the risk for coastal flooding around times of high tide has ended as the tidal departures will stay below flood stage (though they will creep into action stage from time to time). One less thing to worry about, at least. Enjoy the weekend!
The whiff of fall we’ve felt the past day or two starts to retreat a bit as we head into Friday and the weekend. (All good things…)
We do get one more really nice start on Friday, though. Expect to start the day in the mid-60s in much of the metro, running closer to 70° near the coast and even cooler further inland. We’ll warm to the low 80s in the afternoon under mostly cloudy skies. Dewpoints will be climbing back into the upper 60s, so while not terribly oppressive, the humidity will be a little more noticeable. It should also support the risk for a few showers and thunderstorms in the afternoon after a couple reasonably quiet days.
The warming trend continues into the weekend. We’re back in the mid-80s on Saturday and the upper 80s on Sunday as dewpoints return to the 70s. Scattered showers and thunderstorms will remain possible each afternoon, but not everyone will see rain, nor will it be the kind of rain to completely ruin the day, either. Just keep an eye out for possible storms and be ready to move outdoor activities inside for a bit.
We’ve got a reasonably comfortable day (especially as late August goes) for Thursday as cool high pressure continues to rule the meteorological roost in our neck of the woods. We start the day in the upper 60s in much of the metro, likely dropping even lower further inland and in more rural locations. Temperatures should warm to the mid-80s in the afternoon, but humidity will be quite tolerable with mid-60s dewpoints expected. Clouds will be on the increase as a coastal trough takes shape, and there will be a risk for a shower near the coast, but much of us get the day in rain-free.
The rest of the work week will feature a cooling trend as high pressure wedges into the area from the northeast and troughing aloft persists. Wednesday should feature a lower storm chance than we’ve seen the past couple days as some drier air takes hold across the area. Temperatures start around 70°, warming to the mid-to-upper 80s in the afternoon with dewpoints in the upper 60s expected.
Thursday into Friday will feature even cooler temperatures as the wedge intensifies over the area; expect mid-80s on Thursday and low 80s on Friday. The intensifying high pressure should lead to a tightening pressure gradient which will drive some gusty winds, particularly around the coast. The onshore winds combined with the recent lunar perigee will also promote coastal flooding around times of high tide (both morning and evening) starting Wednesday evening through at least Friday. Right now generally minor flooding is expected, which is enough to close some of the more vulnerable roads in downtown Charleston.
Shower and thunderstorm chances come back into play for Thursday and Friday as well as more moisture starts to work back into the area, with the best chances of rain closer to the coast. Inland locations may even stay rain-free where drier air is expected to hold firm. No severe weather is expected, though a downpour or two can’t be totally ruled out.
Tuesday looks a lot like Monday did (in the weather department, anyway) as a front continues to meander nearby, keeping the risk for a few showers and thunderstorms in the forecast in the afternoon primarily east of 17-A. Temperatures will follow a similar curve as well — we start in the low 70s (warmer toward the coast) and warm into the upper 80s to around 90° in the afternoon.
As far as storms go, a few folks could see some locally heavy rain thanks to slow storm motions, but otherwise, no severe weather is expected.
Another break from the heat is in the offing this week as cooler high pressure works its way into the area. We’ll really start to feel it beginning mid-week, and it should last well into the weekend.
One front gets by early Monday, stalling out nearby. This should cut down on coverage of afternoon storms, at least, but a couple storms can’t be ruled out as highs head to the low-to-mid-90s. The cooling trend begins on Tuesday as highs top out around 90°, and will continue for the rest of the week as highs fall into the mid-80s with minimal afternoon thunderstorm chances. Lows will bottom out in the upper 60s fairly routinely as well, with even some mid-60s possible in less urbanized locations.
Temperatures start to warm again as we get into the weekend, but highs should continue to run generally in the mid-to-upper 80s with scattered thunderstorm chances each day.
Well, we are back to the heat — briefly, at least — on Sunday as dewpoints head back to the mid-70s ahead of a cold front that could bring stronger storms later in the day. Expect air temperatures to peak in the mid-90s, with heat indices in the mid-100s — shy of the Heat Advisory criteria of 108°, but not by much — at the height of the afternoon.
Attention will then turn to the potential for strong to severe thunderstorms accompanying the front in the late afternoon and evening hours. A thunderstorm complex is expected to develop in the Upstate and will head to the Lowcountry as the day goes on. Given the heat and humidity, the atmosphere looks to be capable of sustaining strong to severe thunderstorms with damaging wind gusts as the main concern. Heavy rain will be a secondary concern, but these storms should be moving fairly quickly so any ongoing flooding shouldn’t worsen. Be ready for conditions to change in a hurry tomorrow evening, and keep an ear out for possible watches and warnings.
High pressure will gradually give way to another cold front this weekend, bringing humidity back to the picture particularly Sunday. However, the return to mid-70s dewpoints will be brief as slightly drier air moves back in behind the front next week.
Saturday will run a little warmer than Friday did. After another cool-ish (relatively speaking) start in the low 70s, temperatures warm to the low 90s in the afternoon as dewpoints creep back up to the upper 60s. This will make it feel more like 95° or so — not a huge jump, but certainly warmer than it’s felt the past couple days. Expect rain-free conditions on Saturday with one more day of high pressure in control before it cedes ground to the approaching front on Sunday.
Sunday starts warmer — back to the mid-70s — and warms to the mid-90s in the afternoon. Dewpoints in the low to mid-70s will yield heat indices around 100-102° at the height of the afternoon. As the seabreeze moves inland and the front draws closer, expect showers and thunderstorms to develop. Guidance doesn’t show much to write home about with the seabreeze activity — generally scattered coverage — but a round of thunderstorms ahead of the front looks like a good bet as we get into Sunday evening. Shear and instability will be favorable for a few severe thunderstorms, with damaging wind gusts the main concerns (though some hail can’t be ruled out, either). If we get greater coverage of seabreeze storms, that could lower the severe weather risk locally, but we’ll need to see how that materializes. Keep an eye on forecast updates for Sunday evening, just in case.
Friday and the weekend look mostly quiet as high pressure remains the main weather player for a few more days. We should start Friday in the mid-to-upper 60s in much of the metro (with low 70s on the coast); temperatures head to the low 90s in the afternoon under mostly sunny skies. With dewpoints in the mid-60s, the heat index could actually run slightly cooler than the air temperature (yes, this can happen!). So, while it’ll still be on the hot side, it won’t be quite as bad as it has been.
Winds go more southerly starting Saturday, and we’ll see a slow uptick in dewpoints as a result, but Saturday still looks quite good. We’ll start in the low 70s, warming to the low 90s in the afternoon under mostly sunny skies once again. Heat indices will run a degree or two warmer than the air temperature, but still generally not too out of bounds especially compared to what we’ve dealt with recently. Dewpoints creep back into the 70s on Sunday, and this will help drive a few scattered showers and storms in the afternoon and evening as another cold front approaches the area. We could see a stronger storm or two, but that’ll depend on the timing of the front. Overall, though, we should have a pretty good weekend of weather. And, given the fact that winds will go more southerly, the risk for coastal flooding is diminished for the upcoming weekend compared to yesterday’s forecast, though a little salt water on Fishburne at Hagood around the evening high tides could still be in play.