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.
Expect less in the way of cloud cover on Tuesday as the front that helped focus some shower and thunderstorm activity across the area on Monday meanders north and high pressure builds in aloft with plenty of dry, sinking air to be found. We’ll stay on the toasty side of normal for mid-May, with lows in the low 70s warming to the low-to-mid-90s in the afternoon. Dewpoints aren’t terribly out of control, thankfully, so heat indices won’t be too much of a factor, only running about 2-3° or so above the air temperature. That said, it’s still quite warm for this point in the year — the normal high for May 20 is 84°.
The week ahead starts with a continuation of the abnormally warm temperatures we’ve been feeling for the better part of the past week, though some relief is in sight as a cold front brings cooler and drier air to close out the week and head into Memorial Day Weekend.
The main weather story for Friday and the weekend will be the unusual midsummer-like heat, especially Friday and Saturday. We may break a record high on Friday — the record high is 94° set in 1941 — as temperatures head into the mid-90s under partly cloudy to mostly sunny skies. Heat indices will peak around 100° or so — not into heat advisory territory but still on the high side for mid-May.
Partly cloudy skies continue into Saturday, though a stalling front could pop a stray storm or two especially further north. Otherwise, expect another quiet and very warm day, with highs in the mid-90s once again expected after a low-70s start. The front meanders around the area on Sunday, keeping partly cloudy skies in the forecast with a stray storm not out of the question. Temperatures should run a touch “cooler” — and by “cooler” I mean around 90° as opposed to 95°.
The 90s stick around well into next week before the next front approaches by mid-week with the next mentionable shower and thunderstorm chances.
Wednesday was the warmest day thus far of 2025, with a high of 89° recorded at the airport. This distinction will be short-lived as high pressure continues to build in on Thursday, sending us to what should be our first 90° readings of the year in the afternoon. Mostly sunny skies are expected to prevail, so be sure to apply sunscreen if you are headed outside for a little pre-summer preview.
We have one more day of scattered storms in store as low pressure aloft opens up into a trough and interacts with the seabreeze in the afternoon. Once again, we get off to a very mild start with lows in the upper 60s expected. Temperatures will head to the mid-80s before scattered storms initiate along and ahead of the seabreeze. Some brief downpours will be possible, but not expecting a repeat of what we saw this past weekend, either.
Much quieter weather is expected for Tuesday as a surface front moves by, shunting the plume of deep moisture that has absolutely soaked us for the past few days offshore and allowing the sun to break out. There’s still going to be some cloud cover, but we should get a good chance to dry out today.
There is going to be the risk for a few isolated storms to pop back up late today into tonight, but otherwise, it should be a good weather day with highs topping out in the low to mid-80s.
Shower and storm chances return Wednesday, but will be relatively short-lived as high pressure builds back in to close out the week, bringing us a sustained stretch of 90°+ highs and perhaps some even warmer heat indices as well.
A pesky mid-level low will continue to keep scattered to numerous showers and thunderstorms in the forecast for the first part of the upcoming week. From there, high pressure returns and sends us right into summer to close the week.
After a reasonably quiet Friday, shower and thunderstorm chances return to the forecast for the weekend, bringing with it a decent shot at some much-needed rain but also the risk for a strong storm or two on Saturday.
May Day will be a partly cloudy affair across the Lowcountry as Atlantic high pressure continues to exert influence over our weather. We’ll start near 60° away from the locally warmer coastline, warming to the mid-80s in the afternoon. It’ll be a bit breezy especially as the seabreeze gets by in the early afternoon, but otherwise no major concerns are expected.
