High pressure off the Atlantic Coast on Monday, June 17, dominated the weather through Thursday. It provided drier conditions, partly cloudy skies, and seasonable temperatures, with lows in the mid-to-low 70s and highs in the lower 90s.
A tropical disturbance moved onshore along the northeast Florida coast on Friday. Combined with the position of the Bermuda High, southerly winds brought hotter, more humid weather into the region. The circulation and deep moisture associated with the tropical disturbance helped trigger isolated showers across sections of the Coastal Plain on Friday and into the weekend.
Well above normal temperatures and high dewpoints on Saturday and Sunday caused heat index values to rise over 100 degrees. The National Weather Service station at Myrtle Beach recorded a new daily record high minimum temperature of 80 degrees on Saturday morning. Locations in the Upstate recorded heat indices in the upper 90s, with a few stations reporting values over 100 degrees on Sunday. The NWS station at the Florence Regional Airport reported a heat index of 107 degrees on Sunday afternoon, and many locations in the Midlands had heat index values near 105 degrees.
(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 | 0.00 | 27.05 | 4.3 |
| Greer Airport | Trace | 28.88 | 5.3 |
| Charlotte, NC Airport | 0.00 | 23.32 | 2.4 |
| Columbia Metro Airport | Trace | 22.03 | 1.4 |
| Orangeburg 2 (COOP) | 0.33 | 16.97 | -6.3 |
| Augusta, GA Airport | 0.48 | 18.24 | -3.0 |
| Florence Airport | 0.00 | 17.44 | -2.0 |
| North Myrtle Beach Airport | Trace | 16.63 | -2.0 | Charleston Air Force Base | 0.99 | 22.98 | 2.0 |
| Savannah, GA Airport | 1.49 | 22.11 | 0.4 |
| *Weekly precipitation totals ending midnight Sunday. M - denotes total with missing values. s - denotes total with suspect data. |
4-inch depth soil temperature: Clinton: 80 degrees. Columbia: 82 degrees. Barnwell: 76 degrees. Mullins: 75 degrees.
Most of the state recorded less than a tenth of an inch of rain, and many locations in the Upstate reported no rainfall during the period. Storms at the end of the period produced high rainfall totals in parts of Berkeley, Charleston, Colleton, and Dorchester counties. However, the extent of the abnormally dry (D0) on the U.S. Drought Monitor expanded across the Coastal Plain into parts of the Midlands and Pee Dee regions. Conditions worsened in portions of Berkeley, Clarendon, Dorchester, and Sumter counties, so moderate drought (D1) was expanded into these areas, with a small portion of severe drought conditions (D2) added to Clarendon and Sumter counties.
The continued lack of widespread rainfall caused the 14-day average streamflow values at gauges across the state to decrease further, and most of the gauges reported flows below average. In addition to the streamflow values on the Black River at Kingstree, additional gauges in the Pee Dee and the headwaters of the Santee-Broad watershed dropped to below-average levels. River height gauges across the state remained below the action stage. Tidal gauges recorded some tide levels reaching the action stage due to the relatively dry week.
