After a preview of fall-like weather last week, the pattern this week shifted back to a more summer-like regime. A strong upper-level ridge signaled the return of hot and humid conditions to the Palmetto State for the start of the week.
The morning of Monday, August 27, started off with minimum temperatures in the low to mid-60’s across the Upstate and even into parts of the Midlands. A few stations reported morning temperatures up to 4 degrees below normal, including the National Weather Service station in Winnsboro that observed a low temperature of 64 degrees. By the afternoon, high temperatures across the state climbed into the upper-80's to mid-90's. The only portion of the state that escaped the midday heat was the NWS station at Caesars Head, which reported a high temperature of 74 degrees. Spotty shower activity fired up during the late afternoon along coastal portions of Charleston County and the CoCoRaHS stations on Johns Island, Morris Island and near Mount Pleasant reported between 0.50 and 1.00 inches of rainfall. Tuesday, August 28, was essentially a repeat of Monday's weather, as the high pressure at the surface and aloft remained in control and temperatures were about 5 degrees above normal. The NWS stations in Clemson, Greenville-Spartanburg Airport and Pickens observed high temperatures in the low to mid-90's. Showers and thunderstorms developed due to a shortwave across the Lowcountry and rainfall totals up to two inches were reported in many locations along the coast.
The weather pattern continued to be stagnant going into Wednesday, August 29, however, the strong upper-level ridge began to weaken, allowing a weak cold front to approach from the north and a return of moisture into the state. The CoCoRaHS station Mount Pleasant 1.0 WSW (SC-CR-99) reported 2.14 inches of rain for the 3-day period, with most of that total from the rainfall on Monday. An isolated storm in Greenville County dumped 1.30 inches of rain, observed by CoCoRaHS station San Souci 3.3 ENE (SC-GV-27). Despite the isolated shower activity, this was the second week with little to no rainfall over large portions of the state and leading to the expansion of abnormally dry conditions (D0) via the U.S. Drought Monitor. As of Thursday, August 30, the D0 Drought Classification has been added to Calhoun, Chesterfield, Darlington, Fairfield, Kershaw, Lee, Lexington, Richland and Sumter counties.
A weak cold front stalled north of the Piedmont on Friday, August 31, but provided the environment for thunderstorms to form near the South Carolina and North Carolina line. Thunderstorms produced strong winds near Fort Mill, SC (York County), knocking down trees and power lines around the area. CoCoRaHS stations around Rock Hill reported up to 1.81 inches from these isolated storms, while the remainder of the state was dry. The hot and humid air returned for the weekend, and on Saturday, September 1, high temperatures across the state were more than 5 degrees above normal, with the NWS station in Darlington tying a record high temperature of 97 degrees, set back in 1993. Thunderstorm winds knocked down trees and power lines in the greater Tigerville area in Greenville County on September 2, and, on the same day, Clarks Hill broke a record of highest minimum temperature with 73 degrees; the previous record was 72 degrees set back in 2016.
During August, only areas around Charleston and Greenville had near normal rainfall totals. Many stations reported no rain for more than 15 days during the entire month. The NWS Station in Andrews had 24 days with no measurable rain, and the stations in Saluda, Laurens, Anderson, Florence and Chester had 22 days with no reported rainfall. Both maximum and minimum temperatures were slightly above normal across the state, though there were some NWS stations in the Upstate, such as Walhalla, that were slightly below normal.
(Note: The highest and lowest official temperatures and highest precipitation totals provided below are based on observations from the National Weather Service Cooperative Observer network and the National Weather Service's Forecast Offices.)
The highest temperature reported was 99 degrees at the Orangeburg 2 station in Orangeburg County on August 27 and Cades in Williamsburg County on September 2..
The lowest temperature reported was 53 degrees at Caesars Head in Greenville County on August 27.
The maximum 24-hour precipitation reported was 1.24 inches at the National Weather Service Station in McClellanville in Charleston County ending at midnight on August 28. This total also serves as the weekly total from the station.
The CoCoRaHS Station Fort Mill(SC-YR-52) reported a 24-hour precipitation total of 1.81 inches, ending at 8:00 a.m. on September 1 and is the only rainfall measured during the week at the station.
The state average precipitation for the seven-day period was 0.50 inches.
| Weekly* | Since Jan 1 | Departure | |
|---|---|---|---|
| Anderson Airport | 0.00 | 39.26 | 9.4 |
| Greer Airport | 0.21 | 36.72 | 3.8 |
| Charlotte, NC Airport | 2.44 | 31.77 | 2.8 |
| Columbia Metro Airport | 0.12 | 23.36 | -9.0 |
| Orangeburg Airport | 1.10 | 29.08 | -4.7 |
| Augusta, GA Airport | 0.06 | 31.21 | 0.0 |
| Florence Airport | 0.15 | 32.02 | 1.1 |
| North Myrtle Beach Airport | 0.55 | 38.32 | 2.2 |
| Charleston Air Force Base | 0.40 | 38.22 | 1.9 |
| Savannah, GA Airport | 0.17 | 26.49 | -8.4 |
| *Weekly precipitation totals ending midnight Sunday. |
4-inch depth soil temperature: Clinton: 77. Columbia: 82 degrees. Barnwell: 75 degrees. Mullins: 73 degrees.
Rainfall was sparse across the state the week of August 26-September 2, as only portions of the Lowcountry and some isolated locations in the Piedmont and Upstate received any measurable rainfall. Most of the rainfall that fell during this week was less than one inch, with higher amounts in localized areas. This continued lack of rainfall elsewhere across the state led to a continued drop off in streamflow values in some of the area creeks and rivers; especially in the upper Pee Dee region. The Lynches River near Bishopville is reporting streamflow of 80.5 cubic feet per second (CFS), below the minimum flow of 115 CFS in 2011. Other rivers across the state, such as the Broad River near Carlisle, the Edisto River near Givhans and the Pacolet River near Fingerville are now reporting below normal streamflow values. Only a few rivers across the state, such as the Saluda River near Greenville and the Santee River near Pineville, reported slightly above normal streamflows going into the week of September 2.
Charleston Harbor (CHTS1): 85.1 degrees.
Capers Nearshore Buoy (Station 41029): 83.3 degrees.
Fripps Nearshore Buoy (Station 41033): 84.0 degrees.