Warmer-than-normal temperatures will persist for the next few days, especially ahead of a cold front that will bring some fairly solid rain chances to the area for the first time in a little while on Friday.
A warming trend begins Tuesday as high pressure to the north continues to weaken and winds turn more onshore, ushering in a much more summer-like feel over the next few days. Temperatures Tuesday start in the upper 60s to around 70°, warming to the mid-80s in the afternoon with a mix of sun and clouds. Factor in the upper 60s-lower 70s dewpoints and it’ll feel more like 90°. Like we saw on Monday, a few afternoon showers are possible, though the weakening high also will portend a weakening coastal trough, which should keep the risk for showers relatively low.
Astronomical fall begins on Monday with the autumnal equinox at 2:19 PM, but it will increasingly feel more like summer as the week wears on as above-normal temperatures take hold by midweek.
There’s not too much to write home about weather-wise for Tuesday other than it will be a really nice mid-September day across the Lowcountry. Below-normal temperatures continue, with lows in the low 60s warming to the low 80s in the afternoon under mostly sunny skies. Dewpoints mix down to the mid-50s in the afternoon, making the warmth comfortable. Plus, water levels will fall short of flood stage Tuesday as we get further away from the full moon and the recent perigee, so there are no coastal flooding concerns for the rest of the week, either.
The week ahead will remain generally quiet, but we’ll start to turn warmer later this week as high pressure ridges in aloft. Slight shower and storm chances return to the area for the weekend, particularly on Sunday.
A front which helped stir up another round of heavy rain and flooding in downtown Charleston on Sunday will clear the area overnight into early Monday, yielding a week of comfortable temperatures with occasional slight shower and storm chances.
After a few welcome rain-free days, shower and storm chances return to the forecast for Sunday as a cold front moves into the area. We’ll start the day in the low 70s, working our way into the upper 80s in the afternoon before showers and storms kick off. Some rain could be heavy at times, and lightning may be an issue particularly inland where some stronger storms may be possible. It won’t be an all-day rainout, thankfully, but you’ll want to have your indoor plans ready to go if thunderstorms approach.
Isolated salt water flooding may also be a concern around the 7:47 PM high tide. The current total water level forecast brings the tide right to around 7′, which may be enough to cause a little flooding on the most vulnerable roads in downtown Charleston. The risk for coastal flooding around times of high tide increase throughout the first part of the week with the combination of the full moon, lunar perigee, and northeasterly winds in the wake of Sunday’s front, so stay tuned for Coastal Flood Advisories from the National Weather Service.
Warmer and a little more humid air will return to the area Friday as winds go more southerly. With high pressure remaining in control for a few more days, though, we’ll stay largely quiet weather-wise this weekend before a front starts to affect the area later Sunday.
We’ll start to turn a little warmer on Thursday as high pressure to the northeast breaks down a bit, but we should still get one more good day of low humidity in before we start to see dewpoints begin to climb back toward 70° starting Friday. Temperatures on Thursday start quite comfortably once again, with mid-60s the general rule across much of the area. We’ll warm to the upper 80s on Thursday afternoon with plenty of sunshine. The only fly in the ointment may be some very minor coastal flooding around the 6:19 PM high tide, with water levels currently forecast just below 7′. If water levels trend a little higher, a Coastal Flood Advisory may be issued. Otherwise, though, it’ll be another really nice early September day in the Lowcountry.
The rest of the work week will remain generally quiet (weather-wise, anyway), as high pressure remains in control at the surface. Temperatures will be on a warming trend as we get over the hump and into the second half of the work week as the mid-level trough that’s kept us on the cool side flattens out and retreats a bit north. We’ll also start to see high pressure build back in from the Atlantic for a few days, which turns the flow at the surface more southerly and starts to bring that more warm and humid air back to the area. We’re in the mid-80s Wednesday, upper 80s Thursday, and likely back to around 90° on Friday, with lows steadily climbing with the dewpoints back to around 70° by Friday morning. However, we look to stay rain-free through about Saturday before another front approaches for late weekend/early next week.