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Author: Jared Smith

Jared Smith founded @chswx on Twitter in 2008 as an experiment in disseminating weather data through social media. In the ensuing decade-and-a-half, @chswx has provided live coverage of tropical cyclones, tornadoes, severe weather, and even a couple bouts of winter weather to the good people of Charleston, SC.

Turning cooler and sunny for Sunday

/ March 19, 2022 at 9:16 PM

After a somewhat confounding weather day on Saturday, Sunday’s forecast is much higher confidence with high pressure building in behind a cold front that will swing through overnight. This’ll cool things off nicely, with highs topping out around 70° under sunny skies and low humidity to boot. It’ll be a nice day to get out for a walk or get some yard work done. This will kick off a stretch of a couple days of quiet weather before our next storm system arrives by mid-week, bringing us another shot at showers and thunderstorms for the second half of the work week. (We still can very much use the rain.)

Watching for scattered thunderstorms and possible severe weather this afternoon

/ at 10:38 AM

We’ve gotten off to a fairly benign start here in the Lowcountry, but that may change later today as a cold front approaches. Temperatures as of this writing are in the low 70s already with dewpoints in the low to mid-60s, pretty ripe for this time of year. Cloud cover has ticked up somewhat in part due to anvil blow-off from some thunderstorms already firing in southeast Georgia. Winds have also ticked up some, with a gust to 23 MPH recorded at the airport as of the 10am observation.

High temperatures across the Charleston metro should top out in the mid-to-upper 70s this afternoon before the cold front gets closer to the area. It’s this surface feature, currently moving across Georgia and into upstate South Carolina, which should provide the needed lift to allow for scattered thunderstorm development this afternoon. Wind shear and instability will not be lacking, and with some capping in place limiting more widespread development to start, storms could initially start off as supercells, increasing the severe weather threat. The strongest storms will be capable of damaging straight-line wind gusts and large hail. A tornado can’t be ruled out, particularly where storms interact with the seabreeze, which is forecast to be near the coast for much of the day. Given strong SW winds keeping the seabreeze pinned to the coast, it is unlikely that cooler waters will have a significant impact on storm strength.

Given the initially isolated nature of these thunderstorms and the timing of the cap breaking, it’s going to be very tough to pinpoint who exactly will see storms and when. General thinking, according to NWS, is that the greatest risk of thunderstorms will generally run between 3-9 PM. Trying to pin down too much more detail may be foolhardy without clairvoyance beyond what the science can provide.

Today’s advice is familiar: Stay close to reliable, redundant weather warning sources, one of which should not be your smartphone. NOAA Weather Radio and broadcast stations are two great ways to fulfill this recommendation. Not everyone will see severe weather today — perhaps, deity of your choice willing, none of us will! — but if it does threaten your location, you’ll want to be prepared to receive that warning and take action on it by having a safe space indoors, away from windows.

I’ll have updates today as needed.

Friday & the weekend: Turning unsettled with strong storms possible, but a pleasant Sunday ahead

/ March 17, 2022 at 6:34 PM

It’s turned out to be a pretty nice Thursday after a very foggy start. Temperatures topped out in the low-to-mid-70s across the area with plenty of sunshine emerging in the afternoon.

As we head into Friday and the weekend, another storm system will approach the area, bringing with it another round of showers and thunderstorms for some. Much of Friday should remain dry; temperatures ahead of the front will get into the upper 70s under partly cloudy skies. Thunderstorm chances increase with some upper-level energy moving in Friday evening. There’s an outside shot for a storm to briefly become strong or severe, with damaging winds the main concern, but that risk is conditional on whether any instability can develop.

Saturday could have a bit better severe weather threat as the cold front moves through. Wind shear will be favorable, and as long as Saturday doesn’t stay too overcast or showery, some decent instability should develop. This could lead to thunderstorms with damaging winds and large hail. A tornado isn’t off the table, either, with a little low-level shear indicated in the guidance suite. Temperatures look to head into the upper 70s once again before the front gets through later in the day.

Sunday looks great, though! A cooler and drier airmass will move into the area overnight, yielding lows in the low 50s and highs topping out in the low 70s under mostly sunny skies. It’ll be a little gusty as high pressure builds in behind the front, but there are no other weather concerns.

Quiet weather continues Monday into Tuesday before the next storm system and accompanying thunderstorm chances arrives on Wednesday.

Thursday: Green in your beer, not on the radar

/ March 16, 2022 at 6:28 PM

After some beneficial rain so far this Wednesday, we’ll see shower and storm chances taper off this evening as low pressure lifts northeast and away from the area. There is still the risk of a strong to severe thunderstorm for the next few hours (generally through sundown), so we’ll want to be keeping an eye on the radar for the next little bit.

We take a break from rain on Thursday with partly cloudy to mostly sunny skies for St. Patrick’s Day. Temperatures will rise from the mid-50s in the morning to the mid-70s in the afternoon, and dewpoints in the 50s will make for a good middle ground between “too dry” and “too muggy.” Overall, not a bad St. Patrick’s Day, where the beer will hopefully be more green than the radar.


We’ll warm to near 80° on Friday with increasing cloud cover as another storm system moves through the Mid-South on its way to the Mid-Atlantic. Rain chances look to hold off until late, though. A few thunderstorms will be possible overnight Friday into early Saturday morning, and there once again is the potential for one or two of those to produce damaging wind gusts if conditions line up just right. We’ll keep an eye on how this evolves as nocturnal severe weather is, well, sub-optimal.

Slight shower and storm chances persist into Saturday, after which a cold front will come through and help deliver a rather beautiful Sunday with decreasing cloud cover and highs in the low 70s.

Rest of the work week: Stormy Wednesday, nice Thursday, warm Friday

/ March 15, 2022 at 6:54 PM

Up-and-down weather will finish out the work week with a nearly equal mix of nice and unsettled mixed in.

Wednesday will be the stormiest day of the set as surface low pressure and its parent upper low continue to rumble eastward into the area. Expect numerous showers and thunderstorms for a good bit of the day on Wednesday. One thing we’ll want to watch is if any instability can develop; if so, wind shear will be enough to support some strong to severe thunderstorms across the area. With rain in the area, highs should top out around 70° at best, which will put a governor on any severe threat that might materialize.

The storm system departs overnight Wednesday, and by Thursday, we clear out a bit, allowing for good sunshine and comfortable temperatures in the mid-70s in the afternoon. Should be a nice day to get out and about for lunch!

Friday starts out fairly nice as well — mid-50s for lows remain well above normal for this point in the year — before cloud cover increases ahead of another cold front. Showers could work into the area as early as the afternoon and evening hours, but the best risk of rain from this next storm system will be in the area for Saturday. Sunday, though, looks good with comfortable temperatures and ample sunshine.

Tuesday: Increasing clouds, maybe a shower late

/ March 14, 2022 at 6:43 PM

We’ll return to the 70s tomorrow despite increasing cloud cover as high pressure continues to extend offshore at the surface, pumping in some warmer air on the back end of its circulation. No frost or freeze issues are expected Tuesday morning as temperatures look to stay well in the 40s in the morning.

We’ll be watching an upper low as it cuts off around the Arklatex tonight and slowly rumbles through Mississippi tomorrow. This will help to spin up surface low pressure which will traverse the Gulf Coast Tuesday into Wednesday. Ahead of this low, moisture influx will increase, hence the increasing cloud cover. A few showers will be possible after sunset Tuesday as a coastal trough develops.

The bulk of the rain, though, looks to fall on Wednesday as the surface and upper lows move by the area. We get a break on Thursday before another storm system swings by Friday. Temperatures will continue to run above normal for this point in the year, with mid-70s expected by mid-week.

The week ahead: Warmth returns with some intermittent shower and storm chances

/ March 13, 2022 at 10:06 PM

The week ahead features a return to warmer weather with shower and thunderstorm chances mixed in as the pattern remains somewhat unsettled across the Southeast.

Frost and freeze conditions will give way to warmer — but still a touch below normal — high temperatures across the area on Monday as we warm into the mid-60s. Cloud cover will be on the increase as surface high pressure slips offshore and moisture return improves on the back side of the high. Rain chances begin to tick up later in the day on Tuesday as an upper-level low cuts off over the Arklatex and begins to move eastward, spreading some energy into the area and spawning a surface low pressure system. The cutoff low will move by the Carolinas on Wednesday, and with surface low pressure in place, this will help generate showers and thunderstorms across the area. A couple strong storms might not be out of the question on Wednesday, so that’ll be a trend to watch.

The upper low opens back up into a trough as it moves back into the Atlantic later Wednesday into early Thursday, leaving behind a little bit of ridging and thus quiet weather for the better part of Thursday heading into Friday. Another upper-level low will be moving across the mid-South on Friday, and the associated surface front will approach the area heading into the weekend, bringing some showers and maybe a thunderstorm into our forecast.

Thankfully, there’s no further return to winter in this forecast; no frost and freeze concerns are expected after Monday morning, and temperatures will generally run above normal throughout the week, ranging from the mid-60s on Monday to the low-to-mid-70s Tuesday through Thursday before warming up into the upper 70s to near 80° for Friday and Saturday.

A sunny Sunday, but with an Arctic chill

/ March 12, 2022 at 6:28 PM

After today’s rather impressive cold frontal passage, an Arctic airmass settles into the area tonight into Sunday. A Freeze Warning is in effect through Sunday morning as lows head into the 20s across much of the metro area. Regardless of where you are, I’d take precautions with your plants tonight with freezing temperatures possible all the way to the coast.

Sunday won’t warm too terribly much. Highs will only top out in the low 50s despite full sunshine as the abnormally cold and dry airmass dominates our weather. It’ll be exceptionally dry, too, with relative humidity values dropping below 25% in the afternoon. Jackets and lip balm will be important on Sunday!

The good news is that this is March, and this will be relatively short-lived — we’ll be back in the 70s by Tuesday after one more light freeze possibly Sunday night into Monday morning.

Saturday: Wild day of weather starts with severe storms and ends with an Arctic blast

/ March 11, 2022 at 4:23 PM

Saturday could be a bit of a wild day of weather across the Lowcountry. We’ll start with a strong cold front bringing a risk for strong to severe thunderstorms in the morning, and we’ll finish with Arctic air rushing into the area, leading to a hard freeze for many of us Sunday morning.

Read more »

Friday & the weekend: Rough start, then getting quite cold

/ March 10, 2022 at 6:21 PM

This weekend’s weather encapsulates the power of March in a nutshell: Cold air damming, followed by a severe weather threat, followed by an Arctic blast.

We’ll start Friday within the cold wedge that’s kept it cloudy and chilly across the area today. During the day, a warm front should lift north of the area, scouring out the wedge and putting us back in the warm sector of an approaching storm system. Showers and thunderstorms will be on the uptick as the front approaches, and a few of those could turn strong to severe especially as we get into Saturday morning. Guidance is pretty consistent in depicting a squall line-like feature moving through the area to start Saturday, promoting a damaging wind threat. A tornado or two could be possible inland as well, with that risk decreasing as you get closer to the coast and significantly cooler shelf waters.

After the front gets through Saturday morning, conditions will turn quite windy by afternoon as Arctic high pressure builds in from the northwest. The high temperature will be attained in the morning as we’ll cool off fairly substantially post-frontal passage, with temperatures just in the mid-50s in the afternoon.

Saturday night into Sunday morning, clocks will spring forward and temperatures will fall way back into the 20s in much of the metro area, with freezing temperatures possible to the coast. I’d advise everyone with tender vegetation to be ready for a freeze regardless of where you are; cover or bring in those sensitive plants and do not forget about your pets, either!

The chill will be short-lived heading into the new work week; we’ll be back in the 70s by Tuesday (along with another storm system).