The main weather story for the week was the record high temperatures, continued lack of rainfall that contributed to the worsening of dry conditions, and increased wildfire risk across much of the Palmetto State.
On Monday, September 30, a weak back door cold front slid into the region and increased the chance of showers during the afternoon and evening hours. Some locations picked up beneficial rain, up to an inch, from the isolated storms. The storms that developed in portions of the Lowcountry produced pea to quarter-sized hail near Cottageville and wind damage along HWY 601 in Crocketville and HWY 64 in Walterboro. Along the coast, the King Tide caused a tidal level of 7.55 ft. MLLW at the Charleston Harbor gauge, and shallow flooding was reported in low-lying areas of the coast.
High-pressure at the surface and aloft provided dry and warm conditions on Tuesday, that would persist through the remainder of the workweek. Minimum temperatures started in the lower 70s, nearly fifteen degrees above normal, and rose into the upper 80s to low 90s under mostly sunny skies. This pattern continued into Wednesday, as low and high temperatures remained well above normal for the beginning of October. By Thursday, October 3, National Weather Service (NWS) stations throughout the Midlands and Upstate recorded maximum temperatures in the upper 90s. The NWS station at the Greenville-Spartanburg Airport set a new daily high temperatures record of 98 degrees, which surpassed the original high temperature of 90 degrees in 1986. The record heat continued into Friday, as another back door cold front started to approach the state. The NWS station located on the campus of the University of South Carolina in Columbia reported a maximum temperature of 100 degrees, breaking the daily record of 97 degrees set back in 1954. By the end of the fall heat wave, 40 new daily maximum temperature records were set and 11 were tied, while 13 high minimum temperature records were broken, and six tied the previous records.
The cold front brought a welcome break from the record heat on Saturday for portions of the Midlands, Piedmont and Upstate, with temperatures close to 25 degrees cooler than had been 24-hours prior. In some locations, the high temperatures ranked in the top five coolest on record, including NWS stations in Little Mountain, Saluda, and Winnsboro. Cloudy skies kept temperatures cool and scattered rain showers produced the first measurable rainfall in some parts of the state since the beginning of September. The NWS station at the Wateree Dam reported a 24-hour total of 1.50 inches from a localized thunderstorm. The cool down was short-lived as more seasonable temperatures gave way to highs in the warmer temperatures and clear skies to end the weekend.
September 2019 was the fourth warmest and sixteenth driest statewide since 1895. The National Weather Service (NWS) station in Greenville reported a monthly average temperature of 79.0°F, 6.9° above normal, and September 2018 was the fifth driest on record for the Greenville area since 1884. The NWS station at the Columbia Metro Airport had a monthly average temperature of 80.9°F, 6.2°F above normal. Multiple stations across the state reported 0.00” rainfall during September, including stations in Anderson, Cherokee, Edgefield, Greenville, Greenwood, Laurens and York counties, while many locations reported less than 0.25”. Only locations along the coast had near-normal precipitation for the month due to the heavy rainfall from the passage of Hurricane Dorian at the beginning of September.
(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 | Trace | 26.94 | -7.2 |
| Greer Airport | 0.07 | 36.55 | -0.1 |
| Charlotte, NC Airport | 0.03 | 39.36 | 6.8 |
| Columbia Metro Airport | 0.34 | 27.62 | -8.5 |
| Orangeburg Airport | Trace | 18.55 | -19.4 |
| Augusta, GA Airport | 0.03 | 36.04 | 1.2 |
| Florence Airport | 0.27 | 33.25 | -1.6 |
| North Myrtle Beach Airport | 0.01 | 42.58 | 0.1 |
| Charleston Air Force Base | 0.00 | 36.05 | -6.7 |
| Savannah, GA Airport | 2.64 | 33.71 | -6.3 |
| *Weekly precipitation totals ending midnight Sunday. M - denotes total with missing values. |
4-inch depth soil temperature: Clinton: 71 degrees. Columbia: 77 degrees. Barnwell: 72 degrees. Mullins: 65 degrees.
Most of the rainfall over the seven days fell in the Upstate, mainly through portions of Greenville, Oconee and Pickens counties, where observers reported up to two inches of rain, and with most of those totals the result of one event. Rainfall totals in the Upstate over the last 30- to 60-days are well below normal. Outside of the localized portions of the Upstate, less than half an inch of rain was recorded across the remainder of the state. Streamflow values continued to drop in many of the state's streams and rivers, with several reported flows in the southern portion of the state well below normal for this time of year. The USGS river gauges show below normal to much below normal flows on their 14-day flow product along much of the Savannah (despite being regulated) and in portions of the ACE and Santee Basins. At the time of this report, the real-time streamflow values are much below normal across the ACE Basin in the Lowcountry and along the Savannah. Elsewhere in the state, many gauges are reporting below-normal flows, and those that are reporting ‘normal’ flows are in the lower range of the percentile bracket. Portions of Allendale, Barnwell and Hampton counties in the Lowcountry, along with portions of Orangeburg County, continue to be the driest areas of the state, reporting less than twenty-five inches since the beginning of the year. Totals of over forty inches were present along the immediate coast of the southern coastal counties, while interior locations within those counties measured lower amounts.
Charleston Harbor (CHTS1): 81.9 degrees.
Capers Nearshore Buoy (Station 41029): 81.5 degrees.
Fripps Nearshore Buoy (Station 41033): 82.0 degrees.
