A cold, dry high pressure moved into the region behind a departing cold front on Monday, January 10, and it dominated the weather pattern for the first part of the period. Morning lows in the 30s rose to near-normal temperatures in the mid-50s to low-60s. Temperatures on Tuesday morning were up to ten degrees below normal, dropping into the lower 20s in the Upstate to near freezing at the coast. The National Weather Service (NWS) station at the Charleston International Airport reported a morning low of 30 degrees. When combined with the wind, wind chill values were in the upper teens and lower 20s across much of the state. Despite the sunny skies, daytime temperatures only reached the upper 40s and low 50s, and temperatures were close to fifteen degrees below normal in parts of the Pee Dee region.
Wednesday began with a bitterly cold start, with the coldest temperatures so far this winter observed across the state, with minimum temperatures between ten and fifteen degrees below normal. With clear skies, calm winds, and low dewpoint temperatures, radiational cooling caused low temperatures to drop into the upper teens and low 20s across much of the state. High temperatures moderated back to near normal by mid-afternoon, climbing into the 50s. The fair weather continued throughout the workweek, and temperatures rebounded to near typical values on Thursday and Friday.
Cold air damming set up on Saturday, January 15, as high pressure built into the north of the region. The cold daytime temperatures, up to ten degrees below normal, set up the environment for winter weather to end the period. The biggest weather story of the period was the winter storm that moved across the state on Sunday, January 16, that produced snow, sleet, freezing rain, and rain. The NWS Office in Greer issued Winter Storm Warnings for the Upstate, and areas around and north of Interstate 85 recorded snow and sleet totals between four and seven inches, with localized higher amounts close to ten inches. An Ice Storm Warning was issued for portions near and between the Interstate 20 and 85 corridors. Locations in the Ice Storm Warning area reported up to half an inch of ice accretion, though this region had values between a tenth and a quarter of an inch. The Lowcountry was spared the brunt of the wintry precipitation, receiving beneficial rain to help ease emerging drought conditions. Strong onshore winds around the high tide coast contributed to some shallow flooding in low-lying areas. The Charleston Harbor Tidal Gauge reported a maximum tide of 7.29 ft. MLLW during the event.
An Open-File Report on this event will be published and linked here in the upcoming weeks.
(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 | 0.87 | 2.70 | 0.6 |
| Greer Airport | 1.54 | 4.25 | 2.0 |
| Charlotte, NC Airport | 0.98 | 3.77 | 1.9 |
| Columbia Metro Airport | 1.32 | 3.48 | 1.7 |
| Orangeburg 2 (COOP) | 1.40s | 5.22s | 3.3s |
| Augusta, GA Airport | 1.11 | 3.21 | 1.2 |
| Florence Airport | 1.28 | 3.45 | 1.8 |
| North Myrtle Beach Airport | 2.53 | 3.87 | 2.4 |
| Charleston Air Force Base | 1.16 | 1.59 | -0.1 |
| Savannah, GA Airport | 2.01 | 2.43 | 0.9 |
| *Weekly precipitation totals ending midnight Sunday. M - denotes total with missing values. s - denotes total with suspect data. |
4-inch depth soil temperature: Clinton: 37 degrees. Columbia: 48 degrees. Barnwell: 40 degrees. Mullins: 44 degrees.
The period was predominantly dry, with the rainfall reported during the period falling overnight on Saturday, January 15, and into the morning of Sunday, January 16. Most of the state received at least an inch of rain, though areas measured more, and some recorded less. One of the areas that received less rainfall was the interior part of the Lowcountry, where totals ranged from half an inch to three-quarters of an inch. The Pee Dee received beneficial rain, with CoCoRaHS observers noting rainfall totals of up to two inches. With multiple weeks of rainfall across the state, areas designated in either moderate (D1) or severe drought (D2) by the United States Drought Monitor have started to see some easing of the dry conditions. The same storm that helped produce the rainfall totals dropped between four and seven inches of snow along and north of the Interstate 85 corridor in the Upstate, with up to ten inches in the higher elevations. Portions of the Midlands, Pee Dee, and Piedmont reported ice accretion values up to half an inch.
The additional rain during the period across North Carolina and South Carolina helped improve some streamflow values in the Pee Dee region, which had been struggling since November. Streamflow returned to normal conditions on most of the streams and tributaries of the Pee Dee and Wateree rivers. Elsewhere across the state, streamflow values continued to report near-normal conditions. Some above-normal flows reported along the Edisto River recorded heights just below the minor flood stage during the latter half of the period. All other rivers reported heights below the flood stage.
