The period was marked by increased thunderstorm activity across the state and above-average temperatures heading into the weekend.
On Monday, August 24, warm moist air over the region produced scattered storms, with heavy rain and some stronger thunderstorms in the parts of the Lowcountry. There was minor tree damage reported from storms in Allendale, Colleton, and Orangeburg counties. Heavy rain caused street flooding in the Holly Hill area in Orangeburg County and near Mount Pleasant and Shadowmoss in Charleston County. Evening storms near-shore produced wind gusts of 40 mph at locations around the Charleston Harbor, including a WeatherFlow station at Fort Sumter. The National Weather Service (NWS) station in Laurens reported a 24-hour rainfall total of 2.25 inches ending on Tuesday morning, which broke the previous daily record of 2.00 inches set back in 1905. The unsettled weather continued through midweek and a wind gust of 47 mph at a WeatherFlow station at Plum Island. There were multiple reports of minor wind damage from strong thunderstorms in Beaufort, Charleston, and Colleton counties on Wednesday. Lightning from one of the strong thunderstorms caused a structural fire in Bluffton.
Elsewhere, Hurricane Laura made landfall near Cameron, Louisiana, during the early morning of Thursday, August 27, as a powerful Category 4 storm with maximum wind speeds of 145 mph.
At the end of the period, temperatures across the state were five to ten degrees above average, and multiple stations reported high minimum temperatures that either tied or broke the previous records. The NWS at the Greenville-Spartanburg International Airport observed a low of 74 degrees on both Friday and Saturday, breaking the last daily records on both mornings. The NWS stations in Florence and at the Charleston International Airport tied their low records on the 28th with values of 77 degrees. The station on the campus of the University of South Carolina in Richland County reported 79 degrees, and the station at the Columbia Metropolitan Airport measured a low of 78 degrees. These values replaced the records established at both stations in 2006. With the warmer temperatures and humid airmass, scattered afternoon storms developed over the region on Sunday. Thunderstorms caused heavy rain in Bluffton on Sunday, and standing water was reported on portions of Buckwalter Parkway, and lightning near Pritchardville cause minor roof damage to a residential building. The same complex of storm knocked down numerous large tree limbs on Okatie Highway.
(Note: The highest and lowest official temperatures and highest precipitation totals provided below are based on observations from the National Weather Service (NWS) Cooperative Observer network and the National Weather Service's Forecast Offices.)| Weekly* | Since Jan 1 | Departure | |
|---|---|---|---|
| Anderson Airport | 0.21 | 45.51 | 16.1 |
| Greer Airport | 0.08 | 53.48 | 21.1 |
| Charlotte, NC Airport | 0.25 | 37.19 | 8.7 |
| Columbia Metro Airport | 1.23 | 43.92 | 12.1 |
| Orangeburg Airport | 0.41 | 31.22 | -1.9 |
| Augusta, GA Airport | 1.47 | 44.51 | 13.8 |
| Florence Airport | 1.15 | 46.36 | 16.0 |
| North Myrtle Beach Airport | 0.96 | 37.14 | 2.1 |
| Charleston Air Force Base | 4.02 | 39.82 | 4.4 |
| Savannah, GA Airport | 2.06 | 37.70 | 3.5 |
| *Weekly precipitation totals ending midnight Sunday. M - denotes total with missing values. |
4-inch depth soil temperature: Clinton: 90 degrees. Columbia: 82 degrees. Barnwell: 77 degrees. Mullins: 74 degrees.
Two main portions of the state reported more than half an inch of rain, the Upstate, north of the Interstate 85 corridor, and locations to the south and east of the Interstate 20 corridor. Some places in these two areas measured more than two inches of rain. A CoCoRaHS observer near Edisto Beach recorded 8.10 inches over the period, with more than half the amount measured in a 24-hour total. Not every location picked up beneficial rain over the period. Portions of the Upstate and Piedmont, including locations from Anderson to the Rock Hill/Fort Mill area, recorded less than a quarter of an inch of rainfall. The year-to-date rainfall totals continue to be near- to above-normal values across much of the state. The heavy rain in the Lower Savannah River Basin and Lowcountry continued to help ease the dry conditions that developed in the region due to below-normal precipitation in June and July.
The USGS streamflow data across the state show most of the gauges are reporting normal to much-above-normal values at 14- and 28-days. The streamflows in the regions that received more substantial amounts of rain saw the streamflow values rise, while those gauges in areas that missed out on any rainfall during the period have dropped off.
