MYRTLE BEACH, S.C. (WBTW) — It has been an eventful Fourth of July thus far, especially along the Grand Strand. Showers and thunderstorms fired up around noon and there have been some extremely heavy downpours. On average, the coast received 2-4 inches of rain in just three hours. Totals were significantly higher along the South Strand. Garden City Beach reported 6.6 inches of rain and isolated totals in the vicinity saw almost eight inches. A flash flood warning is in effect for coastal Horry and Georgetown counties until 7 p.m.

Rain is expected to clear out between 8 and 9 p.m. which seems to be perfect timing for firework festivities. Isolated rain chances still cannot be ruled out, but mostly cloudy skies will take over and temperatures will bottom out in the mid-70s. Another extremely humid night.

Beginning tomorrow the main focus is going to be on extreme heat, especially throughout the Pee Dee. No heat advisories are in place, but that is likely to change. Triple-digit heat indexes are forecasted tomorrow through Thursday. Tomorrow high temperatures will be in the low-90s for the Pee Dee and mid-80s inland with a heat index in the mid-90s for the beaches and near 102 degrees inland.

Tomorrow will see isolated showers and thunderstorms during the afternoon and that will be the case for most of the week. The hottest day is Wednesday mid-90s inland and near 90 degrees on the coast. The heat index will be near 100 degrees for the Grand Strand and topping 105 degrees throughout the Pee Dee.