On Monday, September 18, a strong high pressure moved in behind the cold front that controlled the weather through the middle of the work week. The quiet start to the period was marked by dry air and mostly sunny skies. Overnight temperatures on Monday, Tuesday, and Wednesday were in the upper 50s to low 60s, up to ten degrees below normal, feeling more like early October than the middle of September. Maximum temperatures were near average, with highs ranging from the upper 70s to low 80s across the state.
There were generally fair conditions across the region on Thursday, as high temperatures were slightly cooler than usual under a mixture of sunshine, clouds, and some scattered showers. On Thursday, an area of low pressure off the Florida and Georgia coasts organized into Potential Tropical Cyclone (PTC) 16, eventually becoming Tropical Storm Ophelia on Friday afternoon.
Tropical Storm Ophelia made landfall near Emerald Isle in North Carolina on Saturday morning and moved northward through Virginia and across the Delmarva Peninsula by the end of the period. While most of the storm's impacts remained north of the state, portions of Georgetown and Horry counties recorded between two and three inches of rain. High surf and rip current advisories were issued for the coast. By Sunday, the remnants of TS Ophelia continued to move through the Mid-Atlantic, and dry air funneled back into the region, providing fair weather headed into the next work week.
(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 | 0.00 | 39.97 | 5.5 |
| Greer Airport | Trace | 45.14 | 8.3 |
| Charlotte, NC Airport | Trace | 36.39 | 3.6 |
| Columbia Metro Airport | 0.00 | 45.93 | 11.1 |
| Orangeburg 2 (COOP) | 0.00 | 47.38 | 8.3 |
| Augusta, GA Airport | Trace | 51.35 | 17.1 |
| Florence Airport | 0.70 | 39.70 | 4.8 |
| North Myrtle Beach Airport | 0.98 | 34.02 | -2.7 | Charleston Air Force Base | 0.06 | 43.38 | 2.4 |
| Savannah, GA Airport | 0.01 | 34.95 | -3.0 |
| *Weekly precipitation totals ending midnight Sunday. M - denotes total with missing values. s - denotes total with suspect data. |
4-inch depth soil temperature: Clinton: 69 degrees. Columbia: 74 degrees. Barnwell: 70 degrees. Mullins: 65 degrees.
The highest rainfall totals during the period were from CoCoRaHS observers in Charleston County, reporting their 24-hour amounts ending on Monday morning. A few observers in Georgetown and Horry counties measured seven-day totals of over three inches of rain. However, outside the coastal areas, most rainfall totals reported across the state were less than an inch, with most of the Upstate recording no rain. The US Drought Monitor (USDM) released on September 21 depicted lingering areas of abnormally dry (D0) and moderate drought (D1) conditions in portions of the Midlands and Upstate, with D0 conditions being introduced into Abbeville, Greenwood, and McCormick counties.
Streamflow values across the Midlands and Upstate remained within the normal range. However, some gauges reported streamflow values below normal, especially in the upper Broad and Saluda River basins. Values in the Pee Dee watershed were slightly above normal. At the same time, streamflow gauges across the Lowcountry continued reporting values that were above average from the heavy rain from Sunday, September 17. River height gauges across the state and tidal gauges along the South Carolina coast reported levels below flood stage.
