After topping out around 70° today, temperatures will aim ever warmer for Wednesday and Thursday before a dry cold front knocks temperatures down a bit for Friday. Mostly sunny skies will be the rule throughout, and with winds more out of the west, the risk for coastal flooding will decrease, too. Weather looks to get even warmer as we get into the weekend, too, with rain chances maybe returning to the forecast next Tuesday.
We’re getting close to the last freeze dates of the season (the median last freeze at North Charleston is March 8), but we can still have bouts of freezing temperatures well into early April, so be cautious if you begin planting. To that end, though, the National Weather Service has restarted the frost and freeze program as of today, which means Frost Advisories and Freeze Warnings will once again be issued by the NWS office when conditions become questionable for vegetation. If those end up being needed at any point, I’ll pass them on.
After topping out in the upper 70s today, we’ll likely see temperatures breach 80° for the second time this year on Wednesday away from the cooler coastline as southerly flow around Atlantic high pressure keeps a very mid-spring-like feel to our weather in place. The temperature difference between the coast and just 10 miles inland could be pretty abrupt — highs may struggle to 70° at the beaches — thanks to the cooler nearby shelf waters and the potential for sea fog (more on that in a second). This pattern stays in place through Friday before a front swings through and cools us off quite significantly for the weekend.
One fly in the ointment will certainly be the potential for sea fog given such warm air over relatively chilly shelf waters. Short-term high-resolution guidance is in decent agreement that a sea fog bank could creep up the coast throughout the day Wednesday, lowering visibilities at the beaches and keeping temperatures some 10-15° cooler where fog hangs around. Southwesterly winds look to keep fog from penetrating too far inland, but that’s something we’ll keep an eye on as well for potential travel impacts. Sea fog will remain a bit of a wild card in the forecast through the end of the week, so stay tuned for tweaks.
The rest of the work week will feature ever-warmer temperatures as a cold front approaches the area. Wednesday will be our last largely rain-free day, though, as shower chances enter the forecast for Thursday afternoon as the front gets closer. We could even hear some rumbles of thunder overnight Thursday into Friday morning. We’ll keep shower chances around for Friday, but peep those highs: mid-70s on Thursday and Friday. It’s been a while since we had a SEWE start out that warm, that’s for sure. Once the front is through sometime Friday evening, temperatures will calm down to more seasonable low-to-mid-60s highs for the weekend with a rain-free forecast expected.
After a couple really dreary days across the Lowcountry, we will finish the balance of the work week with much more sunshine as high pressure builds into the area from the southwest. This’ll not only help clear us out, but the westerly winds will help temperatures moderate as well, with temperatures heading a few degrees above normal to close out the week.
Wednesday may start with some patches of dense fog across the area, with a better risk of fog found inland of 17-A. We’ll want to watch surface temperatures closely, as some spots well inland could be at risk of some freezing fog overnight into tomorrow morning, potentially producing some slick spots on bridges and overpasses near the I-95 corridor. This does not appear to be a concern for Charleston proper, though. If they do form, any slick spots will not last terribly long after sunrise as temperatures quickly head into the 50s before peaking in the low 60s in the afternoon.
From there, the airmass will continue to moderate, allowing for highs in the mid-60s on Thursday and the upper 60s on Friday under mostly sunny skies. We’ll start those days generally around 40°, too, which is right around normal for this point in the year. All in all, not too shabby to close out the work week. Looks like we get Saturday in rain-free, too, but with a few more clouds before rain chances kick back up Sunday as a frontal system moves by.
Our warming trend continues as we head toward Friday before a cold front gets by and knocks Saturday back to normal. Wednesday features partly cloudy skies and highs topping out in the mid-60s, while we go even warmer on Thursday — low 70s for highs! — despite increasing cloud cover as the cold front draws nearer. By Friday, we stay in the 70s, but expect showers to begin to develop and move across the area ahead of said front. We turn much cooler for the weekend behind the front, and will likely stay unsettled pending the development of a coastal low that will head northeastward, keeping rain chances in our forecast into the new work week.
We remain chilly for the rest of the week with below-normal temperatures persisting, but this will feel warm compared to what we’ve got coming for the weekend.
First, though, we’ve got to get through the work week. A cold front comes through early tomorrow, helping to clear out the cloud cover and sprinkles we saw today. Cold air moving in behind said front will keep high temperatures suppressed into the mid-50s despite the increasing sunshine.
Cold air will continue to blow into the area on Thursday, allowing air temperatures to drop below freezing and morning wind chills to bottom out near 20°. It’ll be a good day to layer up; 52° isn’t terribly warm still, but it will certainly feel better than a feels-like temperature of 21° in the morning.
High pressure will then begin to give way to low pressure developing somewhere off the Southeast coast on Friday. This will help generate some scattered showers throughout the day into early Saturday before the low pressure system moves away from the area, potentially bringing quite a snowstorm to the Northeast before it’s all said and done. Said low pressure will drive a sharp cold front through, and lead to weekend highs in the 40s and a very chilly Sunday morning of low 20s.
The temperature rollercoaster will continue as we head into the rest of this abbreviated (for some, anyway) work week. Tuesday will be sunny but still quite chilly as the cold airmass that this weekend’s storm ushered in stays put for another day. High pressure slips offshore Wednesday, though, allowing temperatures to warm up into the low 60s in the afternoon with a little bit more cloud cover working its way in ahead of a cold front. That front will get a little closer on Thursday and could begin to spread some showers into the area into the afternoon hours, but should stay far enough west to keep us in the 60s one more day.
Then Friday rolls around, and the wheels come off in terms of forecast confidence. What is probable is that the front will keep some precipitation around on Friday, and temperatures will be significantly cooler behind said front. The NWS forecast highlights rain showers and highs in the low 40s for Friday as cold high pressure wedges southward. Beyond that, the forecast turns very tricky. Weather models continue to disagree on many of the details of what to expect this weekend, but the potential for at least a little winter weather is increasing. The GFS model has a double-barreled shot of mixed precipitation for Friday night and again over the weekend as it has low pressure developing near the coast and moving northeastward. The ECMWF (Euro) operational model generally shows the primary winter weather threat in the form of freezing rain on Friday night into Saturday followed by dry weather the rest of the weekend.
Suffice to say, it’s a tricky, tricky forecast with more questions than answers at the moment. There are many scenarios, including an all-rain scenario, that are very much on the table. I urge you to continue to monitor forecast updates throughout the week as the details continue to come together, especially with the potential for freezing rain to develop.
After one more freezing cold morning across the Tri-County — perhaps the coldest since late November with lows in the 20s spreading well into the metro area — a warming trend will commence to get us over the hump and into the end of the work week. Wednesday afternoon will feature temperatures running about 5-7° above where we topped out on Tuesday, with upper 50s expected under mostly sunny skies. Cloud cover will tick up overnight Wednesday into Thursday as a weak front approaches, possibly even generating a shower or two. We’ll see more sun on Friday with temperatures remaining within spitting distance of normal for mid-January here in Charleston.
After a couple chilly days post-storm, temperatures will trend back up in a big way for Wednesday as high pressure slips southward, sending winds in a more westerly direction. After just topping out at 54° today, look for highs in the mid-60s on Wednesday with a mix of clouds and sun as a coastal trough lingers nearby. The mid-60s continue into Thursday ahead of a cold front which could bring us a few showers late in the day. By Friday, the front will have cleared and temperatures will once again run in the mid-50s as cooler high pressure builds in from the west.
Expect these cool temperatures to persist into Saturday before warming up big-time on Sunday ahead of a more potent front, which by Monday evening into Tuesday could bring us an even cooler airmass linked to strong high pressure building out of the Plains.
Coastal flooding will once again be an issue with Wednesday morning’s high tide, predicted to peak around 7.5′ around the 10am hour. This will once again cause minor to moderate coastal flooding in parts of downtown Charleston and could close a few roads. Be ready to use alternate routes in case you encounter a flooded road.
2021 is going to close out on a very warm note for the Lowcountry. At the surface, subtropical high pressure will hold firm while the flow aloft continues in a zonal pattern, resulting in an inability to get any fronts through here until the first of the year.
We’ll have at least one or two more opportunities to break record highs before 2021 is all said and done. Wednesday should feature a little less cloud cover, allowing temperatures to challenge the record high of 79° set in 2015. Despite the possibility of some scattered showers Thursday as an upper disturbance ripples by, temperatures should still warm into the upper 70s. (This will fall short of the record of 82°, though, set in 2015.) Partly to mostly cloudy skies return Friday with highs in the upper 70s once again getting close to the record of 78° set in 1996. Indeed, it would be a fitting end to a year that started with a record high — 80° on New Year’s Day.
