After some of us got a day to dry out, showers and thunderstorms look to resume possibly as early as late tonight as a disturbance aloft possibly spawns a little surface low in southeast Georgia. This possible low, if not the associated surface trough, will help to keep numerous showers and thunderstorms in the forecast for Friday and into Saturday as well. We could see storms ongoing Friday morning for the commute, so be ready to take it a little slower on the roads. Heavy rain and lightning will be the primary issues from any thunderstorms. The atmosphere remains juiced with plenty of moisture: precipitable water values (the amount of water you can wring out from a column of air) will continue to run very close to 2″. This moisture combined with ample instability will likely lead to some pockets of very heavy rain rates and a risk of minor flooding to go along with it. Also, it’s worth noting that high tide will peak around 10:17 AM in Charleston Harbor. Guidance does show some heavy downpours coming ashore ahead of and around this time, which could enhance the flood threat in coastal communities including downtown Charleston. With the prevalent storms and cloud cover, highs should top out in the mid-80s at best. It’ll be quite humid, though, and so heat indices could run up toward 90° especially if some sun peeks out.
Saturday looks like it could get off to a similar start as broad surface low pressure may be moving through the area during the morning. Additional showers and thunderstorms could then fire in the afternoon in the wake of the low depending on how well the seabreeze ultimately develops. Temperatures should stay capped in the mid-80s once again, owing to the unsettled weather that’s expected. Something tells me the details around Saturday will be refined some more, too, so stay tuned.
Sunday will be a little more summer-like in nature with more widely scattered thunderstorms, particularly in the afternoon. Temperatures will rebound from previous days into the mid-to-upper 80s.
After record rainfall today — 1.87″ of rain at the airport breaks the record of 1.54″ set in 2000, while stations in West Ashley picked up 2.5-3″ — more storms are on the horizon for the next few days as we remain within a very humid airmass with plenty of upper-air and surface features to help spur on shower and thunderstorm development.
Thursday looks to go similarly to the past couple days, though there may not be quite as much coverage as we’ve seen thus far this week. We could see showers and storms forming early in the day near the coast, with storms becoming scattered to numerous while translating inland with the seabreeze throughout the afternoon. With precipitable water values near 2″, we once again could see pockets of very heavy rainfall. The past couple days have seen a couple 4″ bullseyes, and I can imagine that will be the case somewhere again tomorrow. The severe weather risk remains very low given the very saturated atmosphere, but lightning and isolated bouts of excessive rainfall will make any thunderstorm dangerous. High temperatures will remain suppressed in the mid-80s, though the humidity will still be rather swampy.
A front will sag southward across the area on Friday, bringing with it some cooler temperatures and a slight chance of afternoon thunderstorms. We’ll lop about 6-8° off today’s observed high of 96° tomorrow as winds turn a little more onshore as the front gets by. Only a few of us will see storms tomorrow, so keep the watering gear on standby as you’ll probably need it for a few more days.
Ridging aloft will continue to build into the area for the weekend, but east to northeast winds at the surface will help keep temperatures and humidity (to an extent) in check. Expect highs in the upper 80s to around 90° each afternoon with dewpoints running in the upper 60s, yielding heat indices in the low 90s. Mostly sunny skies will be the rule with the somewhat drier atmosphere and sinking air keeping updrafts in check. While the air won’t feel quite as nice as last weekend, it’ll still be a good couple beach days. Pack the sunscreen!
Thursday will be the hottest day this week as air temperatures return to the mid-to-upper 90s across the Lowcountry in the afternoon. Unfortunately, dewpoints will also have recovered back into the 70s, and that could put us close to heat advisory territory for Thursday afternoon as heat indices could approach 105°. There will, however, be a shot at some isolated thunderstorms later in the afternoon into the evening hours as the seabreeze makes its move inland. Lightning and gusty winds will be the primary concern from any thunderstorm that forms, but so far widespread severe weather doesn’t look likely.
We have another potentially boy-band-hot (98°) day on tap for Friday as temperatures soar ahead of a cold front. Expect heat indices to once again approach 110°, with a heat advisory a near-certainty as a result. Said heat and humidity will translate to plenty of thunderstorm fuel for potential strong to severe thunderstorms in the evening hours ahead of the front. There’s still model disagreement about exactly when and where thunderstorms will fire, but if and when they do, a few will be capable of damaging wind gusts. You’ll want the weather radio nearby tomorrow evening, especially if you are out and about.
The front gets through late Friday into early Saturday, shutting off rain chances and even helping to dehumidify us a touch. Saturday will still be hot, with air temperatures reaching the mid-90s, but dewpoints in the upper 60s as opposed to the mid-70s will keep heat indices generally below 100°. Sunday looks even better — honestly a pretty fantastic day to get outdoors, particularly in mid-June — with a punch of cooler and drier air keeping air temperatures to the mid-80s for much of the area. The respite will be short-lived, though, as temperatures soar once again by the middle of next week, possibly flirting with 100° on Wednesday.
Thursday will run a little cooler — 91° with a heat index of 94° certainly qualifies — as onshore flow behind a backdoor cold front gives us a little break before the heat picks back up on Friday. With the slightly cooler weather comes a somewhat more stable atmosphere, which will keep the risk for afternoon showers and thunderstorms to a bare minimum. All in all, should be a fairly decent day for an outdoor dinner. (Might still be a bit much for eating lunch outside, though.)
Friday and the weekend will remain on the warm side, with the best chance at showers and thunderstorms coming on Saturday before tapering off on Sunday.
We’ll be the beneficiary of some drier air on Friday, which should help keep thunderstorms to a minimum and put a little governor on the humidity. This will be short-lived, though, as the front that helps to usher in this drier air lifts back north of the area, putting us back in the soup on Saturday. It looks like showers and thunderstorms will begin to break out by mid-morning and continue well into the evening hours. Exact placement of storms will be driven by where storms initially fire and the subsequent propagation of outflow boundaries and the seabreeze. The trough driving some of this unsettled weather begins to lift north on Sunday, leaving us with generally standard chances of thunderstorms on the seabreeze in the afternoon.
Overall, expect highs around 90° each day ahead of thunderstorms, with heat indices generally in the mid-90s. This’ll feel cool compared to what’s coming down the pike for next week — it looks like we might have a few days of near-heat advisory conditions (heat indices 105°+) with little in the way of storms to help cool things off at least temporarily. We’ll want to watch trends closely for this potentially sweltering heat!
Despite the air temperature topping out around 91°, Thursday’s going to be the hottest day of the week because of quite a bit of humidity. Heat indices could approach 100° in the afternoon before scattered thunderstorms develop along the inland-moving seabreeze. A storm or two could be on the strong side where outflow boundaries intersect, but as is typical in the summertime, any severe weather will be quite localized. Heat will certainly affect everyone, though, so be sure that you’re getting plenty of water and shade if you’re outdoors in the height of the afternoon.
We have one more fairly hot day in store before a cold front moves into the area later tonight, bringing with it some unsettled weather — perhaps a strong thunderstorm or two — before moving through and stalling out to our southeast, keeping rain chances in play for the weekend (though turning a little better by Sunday).
Today will start as the past few days have, with temperatures heading into the 90s by early afternoon. Around 2-3 PM, we should start to see showers and thunderstorms fire on the seabreeze — perhaps as close to the coast as the US-17 corridor — before gradually moving inland with time. At the same time, we’ll be watching the cold front to our north and west continue to press into the Carolinas. With the seabreeze, other colliding outflow boundaries, and the approaching front, a couple storms could turn strong to severe, particularly inland. Damaging wind gusts are the primary concern.
The convection-allowing models hint at a lull in the activity this evening before the front gets through the area, perhaps spreading some showers and a few thunderstorms into the area after midnight. Once the front gets through, we will feel somewhat cooler temperatures for the weekend courtesy of winds turning east and northeast as high pressure wedges in from the north. Winds could be a little breezy thanks to a pressure gradient between the aforementioned high pressure and what is expected to be Tropical Storm Alex as it passes well to our south. Alex could also help bring some additional moisture into the area particularly on Saturday, which will keep shower and thunderstorm chances elevated throughout the day (though the highest in the afternoon with daytime heating). By Sunday, the atmosphere dries out a little, but a few hit or miss showers and thunderstorms remain possible into the early evening.
Bottom line for your weekend: It won’t rain all day at any one particular location, but have that rain plan ready to go for any outdoor activities, particularly on Saturday when the probability of precipitation is higher. (And enjoy the cooler temperatures!)
Another hot day is in store for Thursday as highs once again soar into the 90s under partly cloudy skies. Add humidity in, and heat indices could reach 96-97°. There’s a slight chance of a popup thunderstorm or two tomorrow, but the vast majority of us once again look to remain rain-free. If storms do fire, they could produce some gusty winds, heavy rain, and cloud-to-ground lightning, so be ready to move indoors if you’ve got outdoor plans tomorrow afternoon.