We will close out September with a weather winning streak intact. Temperatures will gradually moderate into the mid-to-upper 80s as we get into midweek with mostly sunny skies each day. We could see a front swing through later in the week; while it will be moisture-starved, it might be able to squeeze out a storm or two. Then, back into the low 80s for the weekend, with mostly sunny skies prevailing. Not a bad way to close out the month and head into the fourth quarter of 2021 (already!).
We will remain in a warm and muggy regime on Friday into the weekend as tropical moisture remains in place over the area. We should see a little less shower and storm coverage on Friday as compared to today without much in the way of forcing, but a few airmass thunderstorms will be possible especially ahead of the seabreeze. Saturday looks similar right now as forcing mechanisms remain few and far between. Heading into Sunday, though, upper-level energy will rotate into the area, and this should help enhance shower and thunderstorm coverage especially in the afternoon and evening hours. A total washout is not in the cards, though, so don’t go torching your weekend plans — just keep an eye on the forecast as there will be adjustments and fine-tuning throughout the weekend.
Temperature-wise, we’ll remain generally in the mid-80s each afternoon after starting out in the low 70s each morning (with perhaps some upper 70s to around 80° lows close to the coast, including downtown). Temperatures should be knocked down a peg for Sunday given more expansive cloud cover and shower and thunderstorm activity in the region.
Dewpoints are headed up, and that will bring along a slight chance of thunderstorms for Tuesday afternoon, primarily along and ahead of the seabreeze boundary as it moves inland. We’ll start the day in the low 70s across much of the area before temperatures head into the mid-80s in the afternoon. It won’t be sweltering, but it won’t exactly be fall-like, either.
It’s worth noting that we could see some patchy fog in spots tomorrow morning. Be ready for sudden changes in visibility during the commute, and don’t forget the low beams if you do encounter fog.
After a really nice weekend across the Lowcountry, we’ll get one more day of low humidity for Monday before high pressure weakens and retreats eastward, bringing back a more summer-like feel to the forecast (sans 90° temperatures, at least). Slight storm chances begin Tuesday afternoon, with more scattered coverage expected each afternoon through the weekend. Temperatures look to remain generally in the mid-to-upper 80s each afternoon, with lows rising into the low to mid-70s starting Tuesday.
We have a soggy Thursday coming up as Tropical Storm Mindy, which was named and made landfall on the Florida Panhandle in the space of four hours earlier this evening, moves to our south, bringing along a tropical airmass that will help squeeze out quite a bit of rain particularly in the morning. High tide at 10:19 AM will be of particular interest as high-resolution models strongly suggest that heavy rain will be in the area ahead of and around that time. This could spell a flooding concern for downtown Charleston depending on where the heaviest rain sets up. Be cautious during tomorrow morning’s commute, and be ready to use alternate routes.
The heaviest rain will fall in the morning, but there will be the risk of showers and thunderstorms through the evening as a cold front will move through the area. Once that front’s through, though, we’ll be set up for a nice weekend. Meanwhile, Mindy will be shooed away from the area along the aforementioned cold front, and there are no additional tropical concerns of note for now.
Temperatures will top out just in the low 80s thanks to the prevalent cloud cover and rainfall, well below early September norms. As we head into Friday and the weekend, temperatures will continue to run a little below normal — another taste of fall as we head deeper into September.
Scattered showers and thunderstorms will once again figure into the forecast for Wednesday. An approaching cold front as well as some upper-level help in the form of a trough will contribute to scattered to numerous storms in the afternoon and evening hours. Brief bouts of heavy rain will be possible, and a few storms could get gusty, but severe weather appears unlikely.
We’ll get off to another muggy start with mid-70s lows. Expect mid to upper 80s until storms get going in the afternoon. Mix in the humidity and it will feel closer to the upper 90s.
Finally, we will want to keep an eye on water levels around the 10:12 PM high tide for the potential for some minor salt water flooding as water levels could get near 7’. We might have some rain in the area around that time, too. Thus, time of high tide will merit close watch.
On balance, the week ahead actually looks pretty good. Rain-free but warm conditions (highs ~90°) continue Monday and Tuesday as the ridge of high pressure remains in place across the region. By Wednesday, a cold front and a slug of moisture at least partially sourced from the remnants of Hurricane Ida push southward across the area, scattering showers and thunderstorms across the metro area. The front should clear the area by Thursday, yielding partly cloudy skies and somewhat cooler temperatures with less humidity as we head into the weekend — the first weekend of meteorological fall, which runs from September 1-November 30.
High pressure will continue its influence on our weather as we head into the final weekend of August. Temperatures look to remain in the upper 80s to around 90° each afternoon with warm starts in the mid-70s away from the coastline, where temperatures continue to struggle to get below 80° each morning. The aforementioned high pressure will act to keep shower and thunderstorm activity to a minimum through the weekend, certainly welcomed considering how soggy of an August we’ve had.
High pressure will also keep Tropical Storm Ida, forecast to become a hurricane as it approaches the central Gulf Coast this weekend, out of our hair. Unfortunately, it looks to be another direct strike on Louisiana, an area that is very tropical-cyclone weary after the numerous storms it dealt with last season. If you have friends or family there (as well as in coastal Mississippi and Alabama), please make sure they understand that time is of the essence to prepare as tropical storm-force winds could begin as soon as Saturday evening along the coast. Ida is forecast to make landfall sometime Sunday evening along the Louisiana coast. From there, its moisture may get caught up in a frontal system and help provide the juice for another round of wet weather here next week.
For now, though, enjoy a relatively quiet weekend of weather in our neck of the world.
We’ll remain in a somewhat unsettled regime of afternoon showers and thunderstorms each day this week as tropical moisture continues to hang tough in the Lowcountry. Temperatures will generally top out in the upper 80s to around 90° each day. Mix in the humidity and it’ll feel closer to 100°. Not everyone will see rain every day, nor will it rain all the time, but you’ll want to keep a close eye on the weather if you have outdoor plans this week.
Taking a look at the numbers, it’s been a very, very soggy August. 10.83″ of rain at the airport — including August 15’s 4.08″ deluge — is good for fourth wettest to date (as of August 21). Only 1940, 1969, and 1974 have seen wetter starts to the month. We’re a few well-placed downpours away from making a decent run at August 1940’s monthly record of 17.24″ with ten days to go (including whatever falls between the trace of rain at 5PM through the end of the day).
If there’s one bit of good news, though, it’s that the tropics are largely quiet. Henri made landfall in New England earlier today, and with that, there are no named storms in the Atlantic basin. NHC is keeping an eye on an area of disturbed weather near the Cabo Verde Islands, but as of this writing only gives this disturbance a 10% chance of development over the next five days. Otherwise, a round of Saharan dust is going to help keep things at bay a little bit for at least the next few days — suffice to say, we will take whatever break we can get from the tropics in late August. The climatological peak of the season arrives September 10.
Fred may be long-gone, but its tropical moisture continues to linger across the Lowcountry for another day, making for another round of stifling heat for Thursday. Temperatures will head into the low 90s; combine this with heinous dewpoints in the upper 70s, and that will yield heat indices around 105°. This is getting to the point where heat stroke becomes a real possibility, so be sure to take plenty of breaks in the shade and get plenty of hydration if you must be outside in the heat of the day.
Some will see relief through showers and thunderstorms. In fact, there is a small chance of storms once again in the morning if the High-Resolution Rapid Refresh model has anything to say about it, so we’ll want to watch that trend. Otherwise, we should see another round of scattered afternoon thunderstorms as the heating of the day kicks in and the seabreeze makes its trek. Once again, storm motions won’t be terribly fast, and with precipitable water values at or over 2”, flooding certainly cannot be ruled out in spots.