Expect a bit more in the way of cloud cover and showers for Tuesday as a moisture plume courtesy of Tropical Storm Eta begins to spread northward. Temperatures will remain rather warm for this time of year. We’ll start the day in the upper 60s to low 70s (especially near the coast). Temperatures will top out in the low 80s, with periods of cooling where showers develop. Shower chances will continue to ramp up with time on Tuesday, with thunderstorms becoming likely as we head into Wednesday.
Temperatures will head back above normal this week with shower chances coming back into the picture starting Tuesday. Showers will be isolated to scattered at best for most of the week as a coastal trough persists. Onshore flow will keep dewpoints up, making for a warm and humid mid-to-late October week. Expect highs in the 80s just about every day with lows in the mid-60s. (Closer to the coast, take a couple degrees off the high and add it to the low.)
Astronomical influences and onshore winds will send water levels in Charleston Harbor well into flood stage at times of high tide this weekend. Moderate to major coastal flooding (8.0′ MLLW) will be possible with each morning high tide through at least Monday, while minor flooding is expected with each evening high tide. Road closures will be possible at times of high tide, with some routes becoming temporarily cut off due to salt water inundation.
If you step outside this morning, you’ll notice a welcome lack of humidity as high pressure wedges in from the north, drying out the air at the surface (though cloud cover will remain in place today thanks to some moisture trapped between 4-6,000 feet as well as some upper-level energy that will stir up high cloud cover later today). Dewpoints this morning were running well into the low 60s, with even a reading of 59° at Charleston International Airport at 8am.
Unfortunately, this surge of Fall weather will also come with several rounds of major coastal flooding this weekend into early next week.
So the first thing you will undoubtedly notice in the seven-day is that it is largely bereft of 90s (save for Monday). You may also notice a high of 79° for Sunday. Yes, that’s out there a ways and could still be tweaked upward, but it is just refreshing to see 70s for highs somewhere in the forecast. We’ll need to deal with some rain and coastal flooding to get here, though.
After a rather pleasant weekend, temperatures will begin to trend back above normal this week with chances of showers and perhaps a few thunderstorms each afternoon. Highs will be getting into the mid-80s by midweek, marking a return to that summer preview we were feeling toward the end of March. A cold front will move through the area sometime later this week, bringing a reduction in temperatures, but showers may yet stick around. It’s a fairly low confidence forecast looking toward next weekend with a fair bit of divergence in the models, so stay tuned for updates as things will undoubtedly need to be ironed out.
Holiday travel will become increasingly difficult as a low pressure system develops in the Gulf of Mexico and heads our way Sunday into Monday, bringing heavy rainfall, gusty winds, and the threat for coastal flooding to the area.
8:30 PM:This post has been updated with the latest forecast information.
Sunday will finish with a little more warmth than we’ve had the last couple days as high pressure slips offshore and a front stalls out nearby. Clouds will be on the increase throughout the day, but rainfall is expected to hold off until overnight. Highs will top out in the mid-80s; with dewpoints in the 60s, this will feel a little warmer and more humid than we felt on Saturday.
The second half of 2019 will get off to a fairly hot start, with heat indices running in the low 100s each afternoon. Scattered thunderstorms will provide relief, particularly later in the week. (Must be July in Charleston.)