Despite high clouds passing across the region, the period started with warm and dry conditions on Monday, September 25. Maximum temperatures were up to five degrees above normal, with stations observing highs in the upper 80s. A weak front boundary moved through the state on Tuesday, increasing moisture and rain chances. Most of the rain reported during the period occurred on Tuesday, mainly along the area where the boundary stalled.
High pressure built southeastward along the Appalachians, creating cold-air damming conditions on Wednesday. Cloudy skies and scattered showers were reported across most of the state, and maximum temperatures were up to ten degrees below normal. Highs struggled to reach the mid-70s, and the National Weather Service (NWS) stations in Greenwood and Rock Hill recorded maximum temperatures of 69 degrees. Thursday’s temperatures were still cool under mostly cloudy skies, but clouds eventually eroded by the afternoon, and overnight temperatures in the Upstate dropped into the lower 50s by Friday morning.
High pressure moved back into the region on Friday, controlling the weather pattern through the weekend. Cloudy skies gave way to mainly clear skies and a return to seasonable temperatures. High temperatures were warmer on Saturday and Sunday, with temperatures climbing from the upper 50s and low 60s from the mornings to the mid-80s by late afternoon.
The major story during the period was the astronomical high tides observed from Tuesday, September 26, through Sunday, October 1, at coastal gauges along the South Carolina coast. The tidal levels at the Charleston Harbor gauge ranged between 7.24 and 8.06 feet, with the highest tide occurring on Thursday evening when the gauge recorded a height of 8.06 feet MLLW. The tidal gauge at the Spingmaid Pier also measured its highest tide of the period on Thursday, with a height of 7.97 feet MLLW. These high tide values caused moderate to major saltwater flooding in low-lying coastal areas.
(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 | Trace | 39.97 | 4.7 |
| Greer Airport | 0.00 | 45.14 | 7.3 |
| Charlotte, NC Airport | Trace | 36.39 | 2.7 |
| Columbia Metro Airport | Trace | 45.93 | 10.1 |
| Orangeburg 2 (COOP) | 0.09 | 47.47 | 7.2 |
| Augusta, GA Airport | 0.66 | 52.01 | 16.9 |
| Florence Airport | 0.00 | 39.70 | 3.8 |
| North Myrtle Beach Airport | 0.00 | 34.02 | -4.0 | Charleston Air Force Base | 0.11 | 43.49 | 1.1 |
| Savannah, GA Airport | 0.20 | 35.15 | -3.8 |
| *Weekly precipitation totals ending midnight Sunday. M - denotes total with missing values. s - denotes total with suspect data. |
4-inch depth soil temperature: Clinton: 70 degrees. Columbia: 74 degrees. Barnwell: 67 degrees. Mullins: 65 degrees.
Very little rain fell across the state during the seven days. Areas north and west of the Interstate 95 corridor recorded no rainfall, though a few locations reported totals from trace amounts up to a tenth of an inch. Some interior portions of the Pee Dee region recorded about half an inch of rain from storms on Tuesday, with more widespread coverage with low amounts of rainfall in the Lowcountry. A CoCoRaHS observer near Moncks Corner recorded over two inches of rain from Tuesday’s storms. The US Drought Monitor (USDM) released on September 28 depicted areas of abnormally dry (D0) and moderate drought (D1) conditions in portions of the Midlands and Upstate, with the expansion of D0 conditions to include Anderson, Cherokee, Greenville, Pickens, and Spartanburg counties.
With drier conditions across the Midlands and Upstate over the last two periods, many of the streamflow gauge values dropped below normal, especially in the headwaters of the Broad and Saluda river basins. Some gauges reported streamflow values much below normal, including the Pacolet River near Fingerville and the Chattooga River near Clayton, GA. In the northern Midlands and Pee Dee watersheds, flows on Black Creek and the Lynches River decreased. At the same time, streamflow gauges across the Lowcountry continued reporting streamflow values that were above average, mainly from rain during the period. While the river height gauges across the state reported levels below flood stage, tidal gauges reached moderate to major flood stage heights throughout most of the period due to the astronomical high tides.
