The moist and unstable environment is expected to persist on Thursday and Friday across South Carolina. There’s a chance for flash floods, as well as severe thunderstorms, to develop, especially on Thursday.
The forecast calls for isolated severe storms to impact the central region of South Carolina on Thursday. We are experiencing a significant amount of moisture from the Gulf of Mexico that will interact with a trough approaching from the west. With enough lifting in the atmosphere and enough moisture, as well as heat in place, there could be isolated, severe thunderstorms developing across the eastern portion of the Upstate and through the Midlands and the Lowcountry. The main risk from these severe thunderstorms will be damaging wind gusts that could reach at least 58 mph.
Another factor that must be considered is the chance of flash floods. The Weather Prediction Center continues to put much of South Carolina, except the coast, under a marginal risk, level one of four, with flash flood risk. The ground is well saturated from recent rains, and this trough, along with the moisture and heat, could ignite enough thunderstorms and downpours that another 4 inches could fall.
Friday’s forecast also remains unsettled. Although the trough will be moving away from the area, a few isolated thunderstorms may still occur, especially across the Upstate and the Midlands in the afternoon hours. Keep in mind that the risk for flash floods will be highly dependent on where the highest amount of rain falls on Thursday. If these same regions receive rain on Friday, the possibility of flash floods could increase.
The weekend
A high-pressure system will take the reins on the weekend. We’ll return to regular summer programming, with heat in place, as well as isolated thunderstorms. Temperatures will be between 2° and 4° above average in the afternoon for this time of year, with highs remaining around the low to mid-90s. Lows will stay around the mid-70s.