On Monday, April 21, a strong area of high pressure over the western Atlantic contributed to persistently warm temperatures that lasted through Tuesday. High temperatures of as much as ten degrees above average were recorded. A weak cold front approached the state on Tuesday, stalling over the Midlands and increasing rain chances. Severe thunderstorms swept through parts of Chester and Lancaster counties, causing significant wind damage. Emergency management reported fallen trees, power lines, and structural damage near Fort Lawn and Richburg. Damage was also noted at the Lancaster County Airport, with quarter-sized hail measuring 0.75 inches reported in Richburg.
The stalled frontal boundary led to unsettled weather on Wednesday, and additional severe thunderstorms formed. Wind damage was reported in Allendale County, and hail was recorded in several counties, including Hampton, Georgetown, Horry, McCormick, Greenwood, Newberry, and Lexington. Hail sizes ranged from 0.5 to 1.75 inches. Heavy rain resulted in localized flooding in Barnwell on Thursday, with more than four inches recorded at nearby CoCoRaHS and NWS stations.
The risk of rip currents was elevated along the coast on Friday, and a rip current rescue occurred at the north end of Hilton Head Island. Warm southeasterly winds persisted through Friday and shifted to southwesterly on Saturday ahead of an advancing cold front. Isolated thunderstorms on Saturday produced hail up to 1.5 inches, which was reported near Bonneau in Berkeley County, while hail measuring 1 inch was observed in Greenville County near Mauldin. With the passage of the front, breezy conditions prevailed with northeast winds, bringing a cooler and drier air mass to the region by Sunday. The tidal gauge at the Charleston Harbor recorded a water level of 7.85 ft. MLLW, which resulted in moderate coastal flooding in low-lying 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 | 1.01 | 12.05 | -3.5 |
| Greer Airport | 2.24 | 15.16 | -2.2 |
| Charlotte, NC Airport | 0.22 | 9.89 | -4.2 |
| Columbia Metro Airport | 0.79 | 10.02 | -3.0 |
| Orangeburg 2 (COOP) | 0.89 | 11.00 | -3.7 |
| Augusta, GA Airport | Trace | 10.98 | -3.3 |
| Florence Airport | 0.39 | 9.41 | -2.6 |
| North Myrtle Beach Airport | 0.17 | 7.13 | -5.1 | Charleston Air Force Base | 0.02 | 6.06 | -6.7 |
| Savannah, GA Airport | Trace | 6.81 | -5.9 |
| *Weekly precipitation totals ending midnight Sunday. M - denotes total with missing values. s - denotes total with suspect data. |
4-inch depth soil temperature: Columbia: 71 degrees. Barnwell: 65 degrees. Mullins: 65 degrees.
Measurable rain fell across parts of the state during the period, with areas north and west of the Interstate 20 and 77 corridors reporting widespread totals of at least half an inch of rain. Locations in parts of the mountains received more than two inches of rain. Isolated portions of Barnwell County recorded more than four inches of rain, and about three inches of rain fell in parts of Berkeley, Georgetown, and Williamsburg counties, with most of those totals the result of one event. Scattered showers produced limited precipitation in parts of the Pee Dee and northern Midlands. With the lack of rainfall during previous periods and before the data cutoff of Tuesday morning, the U.S. Drought Monitor map, released on Thursday, April 24, showed the area of severe drought (D2) increased and expanded from northern Charleston County into Georgetown and Horry counties. The moderate drought (D1) conditions were expanded into northern Greenville, Oconee, Pickens, and Spartanburg counties.
Rainfall in the headwaters of the Broad, Saluda, and Upper Savannah river basins helped increase the 14-day average streamflow values at some of the gauges along the main stems and tributaries. However, gauges in the same basins continued to record below normal values, such as Rocky River near Starr, Broad River near Carlisle, and Saluda River at Chappells. Some of the gauges south of the Fall Line, especially in the Pee Dee Basin, also decreased streamflow values, with a few recording values well below normal, including the Waccamaw River at Longs and the Black River at Kingstree. The height levels at the river gauges remained below the flood stage, while tidal gauges recorded minor flooding due to the April King Tides.
