The week started with the first King Tide event of 2020 causing saltwater flooding in low-lying areas along the coast. The tidal gauge at the Charleston Harbor reported values of 7.20 feet mean lower low water (MLLW) on Monday morning and 7.23 feet during the evening hours. Temperatures through the first part of the work week ranged from lows in the upper 50s to low 60s to highs in the low to upper 80s. The National Weather Service (NWS) station at the Greenville-Spartanburg International Airport set a new daily maximum temperature of 88 degrees on Wednesday, April 8, which broke the previous record of 85 degrees set in 2015. Isolated to scattered thunderstorms overnight Monday into Tuesday morning produced the threat of small hail and strong winds with some of the stronger storms across portions of the Catawba and Pee Dee areas. A storm spotter reported pea-sized hail from an isolated thunderstorm near Dalzell in Sumter County, and quarter-sized hail damaged roofs near Boiling Springs in Spartanburg County.
On Tuesday, April 7, the South Carolina Forestry Commission issued a statewide burn ban until further notice to help stop the spread of potential wildfires, partly due to weather, but mainly because of the COVID-19 pandemic and the ability for first responders to combat any fire activity.
The above normal temperatures continued through Thursday, before a strong cold front pushed through the state. The colder air lagged behind the front, allowing temperatures to climb into the upper 80s. However, the air mass was noticeably drier behind the front. Dewpoint temperatures across the state dropped into the single digits in the Upstate and lower 20s near the coast, producing relative humidity values between 20-30 percent. Red flag warnings were issued due to the low humidity values, and Lake Wind Advisories were posted as wind gusts up to 35 mph were reported across the Midlands.
Heading into the weekend, the cooler Canadian air mass built into the region on Friday, April 10. Temperatures moderated to near normal with lows in the 40s and highs in the mid-60s in the Upstate and Midlands to the low 70s along the coast. On Saturday, some locations reported light frost and freeze conditions as overnight lows dropped into the low 30s, before rebounding into the 60s by the afternoon. Moisture returned into the region ahead of a potent storm system that would impact the state late Sunday into early Monday morning. As the warm front lifted northward across the state, temperatures surged in the late evening hours from the 60s into the low to mid-70s, providing an unstable atmosphere that would produce one of the state’s biggest tornado outbreaks on record early Monday morning.
(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 | 0.56 | 21.78 | 8.4 |
| Greer Airport | 0.98 | 22.22 | 8.5 |
| Charlotte, NC Airport | 0.69 | 14.92 | 2.9 |
| Columbia Metro Airport | 0.69 | 16.18 | 4.2 |
| Orangeburg Airport | 0.04 | 12.74 | -0.1 |
| Augusta, GA Airport | 0.16 | 17.22 | 4.0 |
| Florence Airport | 0.26 | 14.33 | 3.8 |
| North Myrtle Beach Airport | 1.14 | 13.66 | 1.3 |
| Charleston Air Force Base | 0.04 | 10.37 | -1.2 |
| Savannah, GA Airport | 0.11 | 12.07 | 0.6 |
| *Weekly precipitation totals ending midnight Sunday. M - denotes total with missing values. |
4-inch depth soil temperature: Clinton: Not Available. Columbia: 67 degrees. Barnwell: 62 degrees. Mullins: 68 degrees.
For the second week in a row, rain totals across the state were less than an inch, despite widespread rainfall during the beginning of the period. The highest rainfall amounts were observed across portions of the Pee Dee and localized areas of the Lowcountry. The breaks between the rainfall events allowed fields to dry out, so agricultural planting could take place in areas that have received above-normal precipitation during the winter
The headwaters of the state’s watersheds in North Carolina continued to miss out on the beneficial rainfall, which resulted in a slow decline in the river and streamflow values at gauges in portions of the Pee Dee and Santee river basins. However, the streamflow levels were still normal due to the multiple weeks of rain that fell during the previous periods.
