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.
Heat and humidity will continue to rule the roost for Tuesday and for the next couple days as we stay within southerly flow at the surface and aloft, keeping the moisture pump moving right along. This will also lead to periods of storms. Guidance is hinting at another round of morning showers and storms near the coast as the land breeze develops before afternoon storms develop further inland. Coverage will generally be scattered in nature, and not all of us will see rain as a result. Highs top out in the low 90s after a start in the upper 70s; expect heat indices to get close to advisory criteria in the afternoon, perhaps approaching 107°.
I’m back…just in time for more rain. Showers and thunderstorms figure prominently in the forecast this week, especially in the afternoons and evenings, as the pattern generally keeps a trough in the east and a ridge in the west. This keeps us within southwest flow aloft, which keeps disturbances rippling through the area at times and the flow of moisture open from the Gulf. This, in turn, translates to potentially numerous showers and thunderstorms each afternoon and evening as daytime heating kicks in and the sea breeze makes its inland trek.
After reaching 99° at the airport on Sunday — the warmest it’s been since May 29, 2019, when it was 101° in the midst of the Memorial Day heat wave — air temperatures make another run for the upper 90s on Monday after another steamy start in the upper 70s to low 80s as a deep-layer ridge stays in place. Given the moisture in place, heat indices should once again reach or exceed Heat Advisory criteria (108°) in many spots, especially in the Highway 17 corridor. A few showers and thunderstorms will be possible once again Monday afternoon and evening along and ahead of the seabreeze, but with the ridge in place, coverage will be scattered at best. Much like Sunday, we can’t rule out a stronger storm where one does fire if it can realize the considerable instability that will be available to it. Additionally, storm motions should again be fairly slow, and with a juicy atmosphere, some localized flooding will be possible if a storm does fire and hang out for a bit.
We’ve got a couple fairly active weather days ahead as low pressure nudges a front back inland across the area starting Friday. Then, heat really starts to build in on Sunday, with a stretch of heat indices well into Advisory territory expected to last several days.
Guidance suggests we could get off to an early start to spotty showers and thunderstorms on Friday before coverage becomes more widespread as the seabreeze kicks in later in the day. Temperatures start in the upper 70s to low 80s, warmest near the coast, warming to the low 90s in the afternoon in-between storms. Factor in dewpoints in the mid-70s and it’ll feel closer to the low 100s. Many of us should see some decent rain; an inch of rain looks to be a good bet in many spots, with some spots receiving upwards of 2″ (and maybe even a little more where locally heavy rainfall occurs). Severe weather is not expected, but minor flooding could occur where storms train. As the sun heads down, expect coverage to decrease.
Storms will continue into Saturday as energy aloft and low pressure at the surface affect the area for one more day. They’ll be a little more scattered in nature, though many of us could see some measurable rainfall once again. After another upper 70s to low 80s start, temperatures head back into the mid-90s in the afternoon with some spots flirting with Heat Advisory conditions (heat indices 108°+) in between storms.
Sunday will turn even hotter, with temperatures heading into the upper 90s in the afternoon. Heat indices should venture into Heat Advisory territory, with fewer storms to cool some of us off as the pattern shifts back to a more traditional summertime setup with the Bermuda high to our east and the seabreeze pushing inland to kick off showers and storms. You’ll want to make sure you’re taking heat precautions if you find yourself out and about during the height of the afternoon. The hot temperatures look to stick around into at least the first part of next week, too, with heat indices perhaps approaching 110° at times with scattered afternoon storms to cool a few of us off.
A stalling front will briefly usher in slightly drier air on Thursday, helping to keep heat indices below heat advisory levels, but it’ll still be plenty warm with air temperatures peaking in the mid-90s and heat indices in the mid-100s expected. We should still see a few showers and thunderstorms pop in the afternoon, but like Wednesday, coverage should be reasonably limited.
Another hot and potentially stormy day is on tap for Wednesday. We’ll start the day in steamy fashion once more, with upper 70s to start the day away from the even warmer coastline. We’ll warm to the mid-90s in the afternoon, and this combined with mid-to-upper-70s dewpoints will yield heat indices in Heat Advisory territory once again. We should see showers and thunderstorms initiate once again in the afternoon along and ahead of the seabreeze, though it’s worth noting that this evening’s convection-allowing models are showing a bit of a quieter day. We’ll see, though, as it’s often the small-scale influences that can help to drive development this time of year.
Thursday should be a little more active as a front stalls out to our west and a mid-level disturbance approaches from the east. Before storms fire, though, it’s another day in Mother Nature’s sauna with air temperatures in the low to mid-90s feeling like the mid-100s, perhaps flirting with Heat Advisory levels once again. Storms should be generally scattered to widespread in the afternoon and evening with heavy rain once again a possibility.
The aforementioned disturbance interacts with the stalled front to keep showers and storms in the area for a good bit of Friday, with coverage peaking in the climatologically favored afternoon and evening. This will keep temperatures from getting too far out of hand, with highs potentially falling short of 90° for the first time in over a week, though it’ll still be plenty warm. Heavy rain and maybe a strong storm or two remain the main concerns as we sit in a rather moisture-rich environment ahead of the stalled front to the west.
Scattered showers and thunderstorms will stay in the forecast for much of the day Tuesday. While it won’t rain all day at any one location, a shower or storm will be possible pretty much anytime especially beyond 10am. Locally heavy rainfall will be possible, but severe weather is unlikely.
We start the day in the upper 70s to low 80s at the coast, warming to the low 90s in the afternoon. Dewpoints in the upper 70s yield heat indices in the mid-100s (though just shy of advisory criteria), which will continue this stretch of uncomfortably steamy weather.
A surface trough and the seabreeze keeps shower and thunderstorm chances in the forecast each afternoon for much of the upcoming week. We’ll stay on the steamy side, though, with temperatures generally in the low to mid-90s each afternoon and lows in the upper 70s inland to low 80s near the coast, where additional record high minimum temperature records could be broken this week.
The Fourth of July should be a generally quiet weather day across the area, featuring partly cloudy skies and generally near-normal temperatures (read: still fairly hot). We start the day in the mid-70s and will warm to the low-to-mid-90s away from the coast, which looks to run more into the upper 80s to around 90°. The heat index will run around 100° as dewpoints remain a touch lower than they have been (generally low 70s). You’ll want the sunscreen with the UV index expected to run close to 10 at the height of the afternoon. Ridging aloft will keep a lid on any thunderstorm activity, removing Mother Nature’s fireworks from the equation this go-around.
After a brief reprieve Tuesday, the heat is turning back up as we head into the Fourth and beyond. Winds stay onshore for one more day Wednesday, which will keep temperatures “only” in the upper 80s to low 90s. Mid-70s dewpoints, though, will make it feel like the upper 90s during the height of the afternoon. Ridging building in aloft will keep a lid on any shower and thunderstorm development.