Wet weather continues overnight Christmas into Tuesday, as showers and thunderstorms with occasional patches of heavy rain continue to move through the area. Flooding will be a concern particularly in the morning as high tide around 7:15am, which should exceed flood stage in Charleston Harbor, could coincide with periods of heavy rain. This combination may produce more widespread flooding than a typical tidal event, making roads impassable and causing them to close. Be ready to route around flooded roads and for delays — perhaps significant — if downtown is in your travel plans Tuesday morning.
Showers and thunderstorms look to continue for a fair bit of Tuesday. We should start to see rain begin to scatter out as we head into the evening, though lingering showers will be possible overnight. Temperatures will be rather mild — the low of 60° is pretty close to the normal high for December 26. We’ll warm to the upper 60s, limited mostly by rain in the area.
Cloud cover will break up some on Wednesday as some drier air moves in. It’ll be another warm day, with lows in the upper 50s yielding to highs around 70° in the afternoon. Some cooler air begins to work into the area on Thursday as cloud cover ticks down, with highs running about 5° or so cooler than Wednesday. Then, a cold front later Thursday will usher in even cooler air, knocking Friday’s temperatures well below normal. Expect lows in the mid-30s to yield to highs only in the mid-50s in the afternoon despite mostly sunny skies.
Unsettled weather arrives for Christmas as a complex and sprawling storm system begins to affect the area. We should see a few scattered showers in the morning through early afternoon, but expect shower coverage and intensity to tick up as we get further into the afternoon and evening hours. Temperatures on Christmas will run much warmer than climatology, though not into record territory. Expect lows in the mid-50s to yield to the low 70s in the afternoon before rain starts to kick in.
Water levels in Charleston Harbor look to reach flood stage (7′ MLLW) with the 6:30am high tide. This will put some salt water on some of the more vulnerable roads in Downtown Charleston, but no rain is expected to coincide, limiting the breadth of any flooding threat.
Generally quiet weather continues through the rest of the week as high pressure remains the prominent feature at the surface and aloft. A chilly night lies ahead Tuesday into Wednesday morning, with temperatures dipping into the 20s across much of the area away from the beaches and downwind from Lake Moultrie. Make sure plants are covered and pets are inside. Temperatures warm to the low 50s — a few degrees warmer than Tuesday’s high of 51° — with mostly sunny skies featuring some transient high clouds at times.
Thursday gets off to another sub-freezing start, but the warming trend becomes more pronounced as ridging aloft strengthens further. Expect highs on Thursday to top out around 60°, once again under partly cloudy to mostly sunny skies.
Friday will still get off to a chilly start in the mid-30s, though most of us should stay above freezing as the airmass continues to modify. Highs on Friday get to the low 60s under partly cloudy skies as mid- and high-level clouds continue to move by.
A cold front will swing through overnight, yielding a much chillier start on Tuesday as temperatures dip down to around freezing away from the coast and downtown. Breezy northwest-to-north winds will make it feel even colder, too, with morning wind chills dipping to the mid-20s across the area. Cold advection will continue throughout the day, and despite full sunshine, northerly winds will likely keep temperatures from heading above 50° in most locations.
Another chilly start is in store for Wednesday as high pressure to our north keeps some cool air blowing into the area throughout the night. This will send temperatures down to the mid-30s once again, with another shot at freezing in a few more secluded spots. Wind chills will dip below 32° at times in the morning, so be sure to dress appropriately. The good news is that we warm up some compared to Tuesday, heading to the low 60s in the afternoon under partly cloudy skies.
The brief warmup doesn’t last long, though: a reinforcing cold front comes through overnight Wednesday into Thursday, ushering in strong high pressure that will not only reinforce the chill — expect highs just to top out in the mid-to-upper 50s — but also kick up the northeasterly winds, which will start to drive tidal departures higher as well, which may lead to minor to moderate coastal flooding in the morning. This strong high pressure will lead to another mid-30s start on Friday, with highs struggling to the upper 50s despite mostly sunny skies. We’ll also need to watch Friday morning’s tidal departures for the risk for additional coastal flooding.
Tuesday will be another sunny day across the area, though you’ll want a jacket as cooler-than-normal temperatures continue. We start the day in the mid-30s, but the wind chill will make it feel around freezing. Some spots well inland could hit freezing, too. Bring in your pets tonight and cover or bring in any sensitive plants, just in case. Temperatures then warm once again to merely the mid-to-upper 50s despite mostly sunny skies as cool high pressure persists. This runs a few degrees below normal; the normal high for December 12 is 63°.
Another cool couple days lie ahead as a reinforcing front comes through early Wednesday morning. This will be a pretty solid shot of cool and dry air as high pressure builds in from the west. We’ll start Wednesday in the mid-40s, but the cooler air rushing in will limit the high to around 60° in the afternoon despite primarily sunny skies. It’ll be a bit breezy, with gusty winds out of the northwest at times, so some element of wind-breaking may be ideal.
Thursday will be the coolest day of the week. We’ll start the day in the mid-30s, with inland locations possibly approaching freezing. A light wind will make it feel a little cooler, with wind chills in the low 30s across the metro. Skies will once again be predominantly cloud-free, but the cold high pressure settling in will hold highs to the upper 50s to around 60°.
High pressure slips offshore Friday, and this allows some warmer air to move back in. We start Friday in the upper 30s to around 40°, but temperatures will warm back toward the mid-60s in the afternoon. Clouds will also be increasing as a coastal trough begins to take shape nearby, but rain is not expected.
A reinforcing shot of cool air arrives overnight, and by Tuesday morning, we’ll wake up to temperatures about 10-15° cooler than we woke up to on Monday. Expect to start the day in the mid-40s before warming to the mid-60s in the afternoon under partly cloudy to mostly sunny skies. These temperatures are right around normal for December 5.
A Freeze Warning is in effect for Tuesday night and Wednesday morning. Expect temperatures to fall into the 20s inland of 17-A, with temperatures around 30° in much of the rest of the metro area. Places closer to the water such as downtown and the islands should stay just above freezing, though frost will be a concern there as well. Bring in your sensitive plants and make sure your pets have a warm place to be tonight.
Tuesday will begin a string of a few chilly mornings across the metro area. Temperatures will start in the mid-30s; breezy northwest winds will make it feel closer to freezing, so bundle up accordingly. (There should be too much wind and too little moisture for frost formation, BTW.) Cloud cover will hang around for the morning before scouring out in the afternoon. Even so, highs will struggle to the mid-to-upper 50s as northerly winds continue to blow cold air into the region.
There will be a chance for a little salt water to creep up out of some drains around Lockwood as well as out of Gadsden Creek with Tuesday morning’s high tide, though it should peak just shy of coastal flood criteria. Still, you don’t want to drive through salt water if you can help it. High tide on Tuesday morning is expected to peak around 8:17am.