Update Thursday 2:30 pm ET: Thunderstorms are blossoming across South Carolina at this hour. The strongest activity was noted on radar north of Columbia, near Rock Hill and Lancaster, where several Severe Thunderstorm Warnings have been issued. Another strong cluster of storms have developed in the Pee Dee region just inland from Georgetown and Myrtle Beach. The storms are expected to continue developing across the Palmetto State this afternoon, capable of producing wind damage, dangerous cloud-to-ground lightning and very heavy rain.
Original post from Wednesday...
The grill won’t be the only thing sizzling this 4th of July in South Carolina. And fireworks won’t be the only booms heard in the sky.
Sizzling Before the Storms
Temperatures will once again soar to the middle 90’s across the state on Independence Day, and the humidity will make it feel hotter. The afternoon heat index will range between 100 and 105 in most areas, and it could even feel close to 110° in parts of the Lowcountry by early evening.
This same level of heat prompted the National Weather Service to issue a Heat Advisory Wednesday for the Pee Dee region, where forecasters said the heat and humidity could make “heat illness more possible”. The South Carolina Department of Health and Environmental Control also issued a “Code Orange” alert for “unhealthy concentrations of ground level ozone air pollution.”
It's not a good day in #SouthCarolina for those sensitive to poor air quality or extreme heat. A "Code Orange" is in effect for the #Midlands and a Heat Advisory has been issued for the #PeeDee region through early evening. #SCETVwx pic.twitter.com/UIEYRITgfD
— SCETV (@SCETV) July 3, 2019
Both of the these alerts are issued when conditions are expected to make it unhealthy for people sensitive to poor air quality or extreme heat. Similar conditions could also occur on Thursday, the Fourth of July.
Nature's Fireworks First
Residents of South Carolina who plan to celebrate the holiday outdoors will want to keep an eye to the sky and the radar. Numerous thunderstorms are expected in the afternoon and early evening hours, some of which could become strong. Atmospheric conditions are expected to be marginally favorable for some cells to produce damaging wind gusts up to 60 mph, small hail, and frequent cloud-to-ground lightning.
The storms are most likely to develop in the early afternoon hours across the Midlands and Upstate region, then move or redevelop further south and east toward the Lowcountry and Pee Dee areas of the state. The slow-moving nature of the downpours could also lead to localized flooding of low-lying or poorly drained areas.
Most of the nature’s fireworks are likely to end in time for the man-made kind that are anticipated across the Palmetto State after sunset. Confidence is high that most areas will be dry by 9 pm, except for areas immediately near the coast in the Lowcountry where showers could linger a bit longer.