Rainfall totals from the passage of a cold front ending the morning of Monday, April 15, were between one to two inches in the Upstate, with a report from a CoCoRaHS station in the Pickens area of 2.14 inches. As the cold front moved offshore, high pressure built over the region and would remain in control of the weather pattern through much of the work week. Gusty winds, up to 30 mph, prompted the National Weather Service (NWS) in Charleston and Columbia to issue Lake Wind and Small Craft Advisories for portions of the Midlands and Lowcountry. Temperatures started the day in the upper 40's to mid-50's and rose to the high 60's to mid-70's across much of the state, under clearing skies. Low temperatures on Tuesday morning were up to ten degrees below normal for this time of year, with many of the stations reporting minimum temperatures in the low 30's to low 40's. The NWS station at Ninety-Nine Islands in Cherokee County recorded a low of 32 degrees. Even with the brisk start to the day, temperatures rebounded into the mid-to-upper 70's, with the NWS station in Darlington topping out with a high temperature of 79 degrees.
The quiet and dry conditions continued into Wednesday, April 17. Minimum temperatures across the Palmetto State dropped to the upper 40's in the Upstate to the low 50's in areas closer to the coast. With the continued clear skies and abundant sunshine, maximum temperatures reached the low to mid-80's. By Thursday, the high pressure began to move offshore, as the weather pattern started to shift ahead of an intense low-pressure system in the central United States. Observed low and high temperatures on Thursday continued to run slightly above normal across much of the state. Portions of the Upstate recorded low temperatures in the mid-40's and highs in the upper-70's, while locations along the coast reported low temperatures near 60 degrees, and highs in the low to mid 80's.
On Friday, April 19, morning temperatures were ten to fifteen degrees above normal, with many stations reporting lows in the upper 50's to mid-60's, ahead of a strong cold front. The high temperatures for the day ranged from the low 70's in the Upstate, due to rain, to the low 80's in areas head of the front. For the second time in less than a week, another widespread severe weather event impacted the state. The Storm Prediction Center issued a Moderate Risk for severe weather on Friday morning, which was the first time for much of the state since April 2017. Multiple rounds of thunderstorms moved through the region, but the main event was associated with a squall line that pushed through the state during midafternoon. More than 150 local storm reports, mostly of wind damage from across South Carolina, as observed wind gusts up to 60 mph were reported at many of the airport stations, with some gusts up to 70 mph observed at isolated locations along the coast. As of this report, there have been six confirmed tornadoes, one in Florence County (EF0), two in Newberry County (both EF1), and two in Orangeburg, one of which was an EF2 with maximum winds of 115 mph, that moved through the Branchville/Rowesville area. The tornado did considerable damage, snapping and uprooting many hardwood and softwood trees, and felling trees on homes and vehicles along its 11-mile-long path. Another EF2 tornado was confirmed in Clarendon County, with maximum winds of 120 mph. The tornado touched down at Camp Bob Cooper and moved across a cove on Lake Marion, causing significant damage to trees and structures near Wilsons Landing. Training lines of showers and thunderstorms across portions of the Upstate caused heavy rains, especially over Oconee and Pickens counties where nearly 20 CoCoRaHS observers reported 24-hour rainfall totals over five inches, with a few close to eight inches.
A weak surface trough lingered across the region on Saturday, April 20, and prevailed through most of the day. Low temperatures were in the upper 40's to near 50 degrees across the state, and the residual shower activity and cloud cover kept high temperatures up to 20 degrees colder than normal. The NWS station at the Greenville-Spartanburg Airport reported a new low maximum temperature for the day of 53 degrees, breaking the record of 54 degrees set back in 1984. Many stations reported their top ten coldest April 20 on record, including the fifth coldest at the Charleston International Airport and sixth coldest at the Columbia Metropolitan Airport. By Sunday, high pressure had moved into the area, and even with the clearing skies, high temperatures were still slightly below normal for this time of year, with daytime temperatures ranging from the upper 60's to low 70's across the state. The high pressure would continue to be in control of the weather for the start of the new work week before another cold front was forecast to move through the state.
(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.)| Weekly* | Since Jan 1 | Departure | |
|---|---|---|---|
| Anderson Airport | 0.73 | 16.64 | 2.3 |
| Greer Airport | 1.46 | 19.19 | 4.5 |
| Charlotte, NC Airport | 0.18 | 18.93 | 6.1 |
| Columbia Metro Airport | 0.30 | 9.36 | -3.4 |
| Orangeburg Airport | 0.51 | 9.87 | -3.8 |
| Augusta, GA Airport | 0.40 | 10.78 | -3.3 |
| Florence Airport | 0.79 | 10.91 | -0.4 |
| North Myrtle Beach Airport | 2.22 | 10.16 | -3.0 |
| Charleston Air Force Base | 0.47 | 6.07 | -6.4 |
| Savannah, GA Airport | 0.29 | 7.63 | -4.8 |
| *Weekly precipitation totals ending midnight Sunday. M - denotes total with missing values. |
4-inch depth soil temperature: Clinton: 56 degrees. Columbia: 65 degrees. Barnwell: 55 degrees. Mullins: 50 degrees.
The rainfall totals across the Palmetto State ranged from half an inch in isolated portions of the Lowcountry, Midlands and Piedmont, with localized amounts up to eight inches across localized parts of Oconee and Pickens counties. Much of the rain during the period fell as the result of two events, a cold front that moved out of the state earlier in the week, and a second cold front that impacted the state on Friday. The significant rain from the event on April 19, caused rivers and streams to rise in portions of the Upstate rapidly. Much of the rain fell in the Piedmont and Upstate, where the year-to-date rainfall totals in parts of the Upstate are over thirty inches, and much of the area is reporting rainfall between four and eight inches above normal, and streamflow values continue to be much above normal in the region. Many of the rivers and streams in the Midlands and Pee Dee responded to the isolated rainfall by remaining in moderate flood stage at the Pee Dee near Pee Dee and the Santee near Jamestown, and minor flood stage along the Congaree and Santee rivers. Despite the rainfall during the week, streamflow values remained near normal along many rivers and streams in the Midlands and interior portions of the Lowcountry and Pee Dee. Areas of the Lowcountry and Pee Dee are four to six inches of rain below normal for the year, having received less than ten inches of rain since January 1, and rainfall totals for portions of the coast are running close to ten inches below normal.
Charleston Harbor (CHTS1): 68.4 degrees.
Capers Nearshore Buoy (Station 41029): 67.3 degrees.
Fripps Nearshore Buoy (Station 41033): 67.5 degrees.
