With a dry high pressure over the area, cooler than average temperatures that started during the weekend continued through the first half of the period. Temperatures ranged between five and fifteen degrees below normal. Highs on Monday and Tuesday were in the low to mid-70s, and overnight temperatures were in the low 50s, with some stations dropping into the upper 40s. By Wednesday, daytime temperatures had warmed slightly, and much of the state reported highs in the lower 80s.
On Thursday, May 12, a low pressure off the coast drifted toward the region, causing cloud cover to increase throughout the day. Locations under the cloud cover recorded below normal highs, while the sunny Upstate had highs slightly above normal temperatures. Scattered showers accompanied the clouds, and the showers became more widespread by Friday. Rainfall totals were generally less than half an inch, but higher amounts were observed in locations impacted by thunderstorms.
The Charleston Harbor Tidal Gauge recorded high astronomical tides ranging between 7.13 feet and 7.4 feet MLLW starting on Thursday morning and lasting through Saturday evening. There were a few reports of shallow flooding in low-lying areas of the coast.
The weekend ushered in a return to more summer-like weather with temperatures in the upper 80s and humid conditions across the state. Despite some lingering cloud cover Sunday night across the state, many were able to observe the lunar eclipse.
(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 | 0.07 | 15.95 | -1.6 |
| Greer Airport | 1.98 | 20.95 | 2.5 |
| Charlotte, NC Airport | 0.08 | 17.31 | 1.3 |
| Columbia Metro Airport | 0.68 | 14.58 | -0.2 |
| Orangeburg 2 (COOP) | 0.12s | 17.42s | 0.7s |
| Augusta, GA Airport | 1.44 | 15.32 | -0.5 |
| Florence Airport | 0.29 | 14.74 | 0.9 |
| North Myrtle Beach Airport | 0.15 | 12.41 | -1.5 | Charleston Air Force Base | 0.13 | 8.54 | -5.9 |
| Savannah, GA Airport | 0.06 | 7.36 | -7.1 |
| *Weekly precipitation totals ending midnight Sunday. M - denotes total with missing values. s - denotes total with suspect data. |
4-inch depth soil temperature: Clinton: 68 degrees. Columbia: 71 degrees. Barnwell: Not Available. Mullins: 67 degrees.
Rainfall totals varied across the state, with most locations south of the Fall Line recording less than a quarter of an inch of rain, and less than a tenth of an inch was measured in the Upstate. The highest rainfall amounts fell again in the Central Savannah River Area, Midlands, and portions of the interior Pee Dee region, where totals were closer to a half an inch. A few higher amounts were measured under localized thunderstorms triggered by the sea breeze in Charleston, Colleton, Georgetown, and Horry counties. With the generally decreased precipitation over the past few weeks, the United State Drought Monitor introduced severe drought (D2) conditions into portions of Beaufort and Jasper counties and expanded the abnormally dry (D0) and moderate drought (D1) designations further inland from the coast.
The lack of widespread precipitation for another week caused an additional drop in the streamflow values across much of the state. The 14-day streamflow averages at many of the gauges of the four main watersheds in the state fell below average. While the Little Pee Dee River gauge at Galivants Ferry continued to measure average flows much below the long-term average flows, three new gauges dropped below 10% of their normal streamflow; the North Tyger River near Fairmont, Rocky Creek at Great Falls, and the Coosawhatchie River near Hampton. All the state’s rivers observed heights below the flood stage.
