On Monday, September 26, temperatures were slightly above normal maximum temperatures, with highs in the mid to upper 80s, ahead of a cold front that gradually moved through the area, ushering in another round of dry air. Behind the front, high pressure would dominate the area. Conditions were breezy by the middle of the week, before Hurricane Ian’s landfall, due to a tight pressure gradient over the region. The northerly wind caused temperatures to be up to ten degrees below normal, with overnight lows in the upper 40s to mid-50s and highs in the 70s.
The main weather story during the period was Hurricane Ian, which made landfall near Punta Gorda, Florida, on Wednesday, September 28, as a powerful Category 4 hurricane. After passing across the Florida Peninsula and emerging over the Atlantic off the coast of Cape Canaveral, Florida, as a tropical storm on Thursday, September 29, Ian strengthened back to a Category 1 hurricane and made a second landfall near Georgetown on the afternoon of Friday, September 30.
Locally, Hurricane Ian produced heavy rain across parts of the Lowcountry and Pee Dee. The National Weather Service site at the Charleston International Airport recorded a 24-hour total of 5.57 inches, which became the fifth wettest September day and the 13th wettest day of any month on record for the station. The same station recorded a maximum wind gust of 68 mph. The Charleston Harbor tidal gauge reached a height of 7.02 ft. MLLW, though the heavy rainfall contributed to some of the flooded streets observed in the area. Further up the coast, storm surge battered the coast, causing significant coastal erosion, damaging docks and piers, and flooding along the Grand Strand. The tide gauge at the Springmaid Pier in Myrtle Beach reached 10.77 ft. MLLW which makes it the third highest tide at the location behind Hurricane Hugo in 1989 (16 ft.) and Hurricane Matthew in 2016 (13.6 ft.). Given the cloud cover and rain, many stations across the state recorded their lowest daily maximum temperature on Friday, September 30.
An Open-File Report on Hurricane Ian will be produced in the forthcoming weeks and linked here when it becomes available.
While considerable cloudiness remained over the region, conditions started to improve over the weekend as the remnants of Ian moved out of North Carolina and toward the Mid-Atlantic. Temperatures remained cooler than usual, with low temperatures in the low to mid-50s and daytime high temperatures in the low to mid-70s.
(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 | 0.15 | 26.73 | -8.7 |
| Greer Airport | 0.78 | 41.18 | 3.2 |
| Charlotte, NC Airport | 2.68 | 33.41 | -0.4 |
| Columbia Metro Airport | 2.13 | 33.39 | -2.5 |
| Orangeburg 2 (COOP) | 2.38 | 43.93s | 3.5s |
| Augusta, GA Airport | 0.09 | 39.32 | 4.1 |
| Florence Airport | 4.00 | 33.16 | -2.9 |
| North Myrtle Beach Airport | 3.53 | 41.03 | 2.8 | Charleston Air Force Base | 5.64 | 44.64 | 2.1 |
| Savannah, GA Airport | 0.27 | 32.27 | -6.9 |
| *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: 69 degrees. Barnwell: 65 degrees. Mullins: 61 degrees.
Most of the reported precipitation came from the passage of Hurricane Ian on Friday, September 30, with a few spotty showers on Saturday, October 1. Areas north and east of the Interstate 26 corridor received the most rain during the period, with widespread amounts of over two inches and localized higher amounts. Some CoCoRaHS observers in Charleston and Georgetown counties reported totals over seven inches. Unfortunately, locations in the Savannah River watershed recorded less than half an inch of rain during the period, which did not help ease the lingering dry conditions in the region.
Despite the rain from Hurricane Ian, the 14-day averages for streamflow gauges varied across most of the state. Gauges in the headwaters of the Santee watershed in Greenville and Spartanburg counties continued to report below-normal levels. At the same time, the rainfall helped improve values in the Midlands and the Catawba-Wateree basin. Gauges on the Lynches River near Effingham and the Little Pee Dee River at Galivants Ferry recorded flows that were below average for the end of September. Elsewhere, most of the gauges in the ACE and the Pee Dee watersheds measured average streamflow values. The river heights on the Black River near Quinby and the Santee at Jamestown rose into action stage, approaching minor flood stage height by the end of the period, while the rest of the state’s rivers observed heights below the flood stage.
