During the early morning of Monday, May 13, a cold front pushed through the state and offshore, ushering cooler and drier air into the region for the beginning of the new work week. CoCoRaHS observers in Georgetown and Horry counties reported between two to four inches of rain from the front, the only rain that was reported across much of the state through the period. The morning low temperatures at many of the National Weather Service (NWS) stations started in the mid-50’s in the Upstate to the mid-60’s near the coast. Behind the front, high temperatures peaked in the upper 70’s to mid-80’s. As the high-pressure system shifted over the area, strong radiational cooling occurred and the lows on Tuesday morning were up to ten degrees below normal, with observed temperatures in the upper 40’s to low 50’s across the state. Most of the NWS stations reported maximum temperatures in the mid-70’s, including a high of 72 degrees at the Greenville-Spartanburg Airport and Charleston International measured a high of 77 degrees. Due to the persistently dry conditions in the Lowcountry, the Drought Response Committee convened on Tuesday, May 14, and based on reports, added 15 counties to the Incipient Drought Category due to lack of rainfall, low soil moisture levels, abundant dry fuels for wildfires and increasing water demands.
The cooler than normal temperatures continued through the middle of the work week. A new daily record low temperature of 46 degrees was set in Andrews on Wednesday, May 15, breaking the previous record of 47 degrees set back in 1996. The morning was also the second coldest low temperature in Charleston (50 degrees), and the fourth coldest minimum temperature on record in Columbia (47 degrees). Cooler high temperatures were on tap again with observed highs across the state in the mid-to-upper 70’s, nearly ten degrees below normal for the middle of May. The temperatures on Thursday morning started in the mid-to-upper 50’s and rose to the low to mid-80’s as the high-pressure system moved off the Southeast coast. The Charleston Harbor tidal gauge observed an astronomical high tide value of 7.21 ft. mean lower low water (MLLW) on Wednesday night and 7.08 ft. MLLW on Thursday night, which caused some shallow coastal flooding along the lower South Carolina coast and in low-lying areas around Charleston.
As the upper-level ridge began to set up across the region, on Friday, May 17, minimum temperatures returned to normal, with lows observed in the upper 50’s to mid-60’s. With the return of southerly flow across the area, the high temperatures climbed into the upper 80’s to mid-90’s across the area, swinging temperatures that had been running below normal for most of the week to above normal for the remainder of the weekend. On Saturday, the temperature quickly climbed from the upper 60’s to low 70’s into the low-to-mid 90’s at many of the NWS stations. The high temperature of 91 degrees at the NWS station located at the Anderson Airport made it the sixth warmest May 18 on record. Due to the increased moisture and warm temperatures, isolated thunderstorms developed during the late afternoon. Multiple reports of hail came in from across the state; dime- to nickel-sized hail near Conway in Horry County; penny-sized hail near Cades in Williamsburg County; up to quarter-sized hail in Pickens County with reports of hail in Pickens, Easley and near Pumpkintown; and pea-sized hail in Saluda County near Batesburg. The summer-like temperatures continued into Sunday as the high pressure continued to dominate the weather pattern. Many locations only dropped to the upper-60’s overnight and rose again into the upper 80’s to mid-90’s, and the trend was forecast to last through the upcoming work week, with temperatures pushing 100 degrees.
(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 | 0.05 | 18.84 | 1.7 |
| Greer Airport | 0.00 | 21.04 | 3.1 |
| Charlotte, NC Airport | 0.00 | 21.48 | 5.8 |
| Columbia Metro Airport | 0.00 | 11.71 | -3.6 |
| Orangeburg Airport | 0.00 | 11.17 | -4.9 |
| Augusta, GA Airport | 0.00 | 14.48 | -1.8 |
| Florence Airport | 0.00 | 12.74 | -1.2 |
| North Myrtle Beach Airport | 0.00 | 11.30 | -4.6 |
| Charleston Air Force Base | 0.01 | 6.92 | -8.1 |
| Savannah, GA Airport | 0.07 | 10.44 | -4.4 |
| *Weekly precipitation totals ending midnight Sunday. M - denotes total with missing values. |
4-inch depth soil temperature: Clinton: 78 degrees. Columbia: 77 degrees. Barnwell: 71 degrees. Mullins: 73 degrees.
Another week of dry conditions occurred across the Palmetto State, with isolated afternoon thunderstorms producing heavy rainfall in some locations, with widespread rainfall falling as a result of a cold front on May 12 and 13. Locations in Georgetown and Horry counties reported totals of up to four inches, especially in the area near Murrells Inlet and Pawley’s Island. Year-to-date rainfall totals of between five and ten inches of rain have been measured in areas from the Interstate 95 corridor to the coast. These totals are six to eight inches below normal for this time of year in the Lowcountry and Pee Dee, and rainfall totals for portions of coastal Charleston and Georgetown counties are running close to ten inches below normal. Spotty showers fell in the Midlands and Upstate, mainly due to the development of afternoon thunderstorms once the warm weather returned to the region during the last part of the week. The dry pattern and lack of widespread rain caused the remaining rivers to drop below action stage. Streamflow values across the state dropped off, and gauges along the Black, Catawba, Edisto, and Wateree rivers were below normal for this time of year. Despite the lack of rainfall, the year-to-date rainfall totals in the Upstate remained well above normal for this time of year, with more than 20 inches reported at many locations and over 30 inches in some of the more mountainous areas. Ten to twenty inches of rain have fallen since the beginning of the year in the Midlands, but the Central Savannah River Area is close to six inches below normal.
Charleston Harbor (CHTS1): 77.9 degrees.
Capers Nearshore Buoy (Station 41029): 77.2 degrees.
Fripps Nearshore Buoy (Station 41033): 76.1 degrees.
