On Monday, October 9, dry air and high pressure continued to provide clear skies and cooler conditions across the state. Morning lows were up to fifteen degrees below normal, with temperatures dropping into the 40s across much of the state. Despite the sunny skies, the afternoon high temperatures only climbed into the mid-70s, which was between five and ten degrees cooler than average for many locations. Temperatures on Tuesday morning were still ten degrees below normal, with the National Weather Service (NWS) station near Andrews in Williamsburg County recording a low of 40 degrees for the second day. Moisture returned to the region as a frontal boundary stalled to the north of the area. Temperatures were slightly warmer than average, reaching the low to mid-80s.
A low-pressure system moved across Florida on Wednesday, October 11, increasing rain chances across the state, especially in the Central Savannah River Area and southern Midlands. The rain started late Wednesday night and lingered into Thursday morning. CoCoRaHS observers in Aiken and Orangeburg counties reported 24-hour rainfall totals ending Thursday morning between two and four inches. With the widespread cloud cover, temperatures were cooler on Wednesday and Thursday. The NWS station at North Myrtle Beach tied its daily record low maximum temperature on Thursday of 64 degrees set in 1952. The NWS station at the Charleston International Airport measured a high of 66 degrees, while the cloud cover cleared in parts of the Upstate, allowing the temperature to hit 72 degrees at the NWS Greer site. The tidal levels at the Charleston Harbor gauge ranged between 7.16 and 7.19 feet MLLW on Thursday, Friday, and Saturday, causing shallow saltwater flooding in low-lying coastal areas.
Even though Friday, October 13, started with clear skies, clouds increased throughout the day, and scattered showers developed during the late evening and overnight. By Saturday morning, some locations in Berkeley, Charleston, Georgetown, and York counties had recorded over an inch of rain. A low-pressure system moved along the Coastal Plain on Saturday ahead of a strong cold front to help keep moisture across the region. The primarily cloudy conditions limited the view of the annular solar eclipse. The cold front moved offshore by Sunday morning, and cooler air filtered into the region due to northwesterly flow. A weak surface trough formed over the area and provided scattered showers late in the evening.
(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.) The highest temperature reported was 84 degrees on October 10 at the station in Santuck in Union County and on October 11 at the NWS stations near Barnwell in Barnwell County and McCormick in Edgefield County. The lowest temperature reported was 32 degrees at the NWS station near Jocassee in Oconee County on October 9. The maximum 24-hour precipitation reported was 3.96 inches at the NWS station near North Augusta 2.3 SSE in Aiken County, ending on the morning of October 12. The CoCoRaHS station North Augusta 1.5 WSW (SC-AK-39) reported a 24-hour precipitation total of 3.43 inches, ending on the morning of October 12.| Weekly* | Since Jan 1 | Departure | |
|---|---|---|---|
| Anderson Airport | 0.96 | 40.94 | 4.2 |
| Greer Airport | 0.73 | 45.87 | 6.3 |
| Charlotte, NC Airport | 0.97 | 37.37 | 2.1 |
| Columbia Metro Airport | 1.53 | 47.46 | 10.1 |
| Orangeburg 2 (COOP) | 3.71 | 51.18 | 9.1 |
| Augusta, GA Airport | 3.96 | 56.00 | 19.6 |
| Florence Airport | 0.87 | 40.57 | 2.8 |
| North Myrtle Beach Airport | 1.49 | 35.51 | -4.7 | Charleston Air Force Base | 1.74 | 45.23 | 0.5 |
| Savannah, GA Airport | 1.15 | 36.30 | -4.7 |
| *Weekly precipitation totals ending midnight Sunday. M - denotes total with missing values. s - denotes total with suspect data. |
4-inch depth soil temperature: Clinton: 63 degrees. Columbia: 68 degrees. Barnwell: 63 degrees. Mullins: 60 degrees.
Unlike the previous period, there was widespread rainfall over the seven days, with most of the National Weather Service and CoCoRaHS stations recording at least half an inch of rain and many stations reporting over an inch. On Thursday, some CoCoRaHS observers in Aiken, Georgetown, Horry, and Orangeburg counties recorded between three and four inches of rain from showers and storms. Due to the limited rainfall in previous periods, moderate drought (D1) conditions expanded to include most of the Upstate on the US Drought Monitor (USDM) map released on October 12. Additionally, abnormally dry (D0) conditions were introduced in Beaufort and Jasper counties.
Despite the rain, the previous drier periods led to the continued drop in the streamflow gauge values along most of the state’s rivers. Multiple gauges in the Broad, Catawba, Pee Dee, and Saluda River basins dropped to much below normal values, while additional gauges in the watersheds reported below-normal flows. The gauges in the ACE River basin reported 14-day average streamflow values within the normal range, but flows had dropped off from the previous period. While the river height gauges across the state reported levels below flood stage, tidal gauges reached moderate heights on Monday due to the astronomically high tides.
