An active period started on Monday, May 13, as high pressure moved offshore, allowing for southerly flow and increasing moisture throughout the day, leading to widespread clouds and rain. High temperatures were cooler than normal on Monday and Tuesday, with highs in the upper 60s to lower 70s. Showers and thunderstorms developed late Tuesday morning and continued throughout the day as a warm front lifted through the region Tuesday night and into Wednesday morning. Thunderstorms produced wind damage in Marion and Marlboro counties, and a funnel cloud was spotted near Green Sea in Horry County. The low pressure that pushed through the state on Wednesday created strong to severe thunderstorms along and near the associated cold front. There were reports of downed trees in Aiken, Darlington, Edgefield, and Lexington counties. Heavy rain was reported with some of the storms, and flash flood warnings were issued in portions of Cherokee County near Gaffney. A few thunderstorms produced hail, including quarter-sized hail in Horry County, ping pong-ball-sized hail in Florence County near Lake City and Georgetown, and golf-ball-sized hail in Clarendon and Williamsburg counties.
Weak high pressure built into the area on Thursday, May 16, providing a brief break in the unsettled weather conditions. Under sunny skies, high temperatures climbed into the mid- to upper 80s by Thursday afternoon. Chances for showers and thunderstorms increased on Friday as a slow-moving low-pressure system approached the region. Periods of widespread showers and thunderstorms occurred during the weekend. Heavy rain on Sunday caused flooding in Charleston and forced the closure of multiple streets downtown. A lightning strike caused minor structural damage to a home in Awendaw. The National Weather Service station at the Beaufort MCAS recorded a 68-mph wind gust, and there were reports of penny- to golf-ball-sized hail across Beaufort County.
(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 | 0.44 | 24.50 | 6.5 |
| Greer Airport | 1.15 | 26.02 | 7.1 |
| Charlotte, NC Airport | 3.69 | 21.79 | 5.4 |
| Columbia Metro Airport | 0.53 | 20.32 | 5.1 |
| Orangeburg 2 (COOP) | 0.56 | 15.10 | -2.2 |
| Augusta, GA Airport | 0.28 | 14.91 | -1.2 |
| Florence Airport | 1.27 | 16.54 | 2.2 |
| North Myrtle Beach Airport | 2.43 | 14.09 | -0.2 | Charleston Air Force Base | 0.58 | 18.95 | 4.2 |
| Savannah, GA Airport | 2.96 | 18.70 | 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: 76 degrees. Columbia: 72 degrees. Barnwell: 66 degrees. Mullins: 65 degrees.
The unsettled pattern provided measurable precipitation across most of the state. Areas along Interstates 77 and 85 recorded more than two inches of rain, with some isolated locations reporting over three inches of rain, especially near Gaffney in Cherokee and Clover in York County. Over the weekend, the low-pressure system helped contribute to the two to three inches of rain that fell over portions of Beaufort, Charleston, and Colleton counties. A few locations recorded less than a quarter of an inch of rain, including Allendale and Hampton counties.
With more than five inches of rain falling over the past two periods, most of the 14-day average streamflow values along rivers and streams north and west of the Interstate 20 corridor reported much above normal values. The gauges on the Pee Dee River near Bennettsville and on Rocky Creek near Great Falls recorded high values. River height gauges across the Coastal Plain reported heights in minor flood stage as the water moved through the watersheds. Along the coast, tidal gauges reached the action stage toward the end of the period due to the upcoming full moon.
