After two weeks of hot and humid weather with strong to severe afternoon thunderstorms dominating the weather pattern, a cold front pushed through the state bringing cooler overnight temperatures and drier conditions through much of the period.
The week started with the weakening of the upper-level ridge as the cold front started to approach the region. Low temperatures across the state on the morning of Monday, July 22, ranged from the low to mid-70’s, although a few stations recorded values in the upper 70’s. The National Weather Service (NWS) station located at the Florence Regional Airport tied the high minimum temperature record for the day of 79 degrees, set back in 2011. The maximum temperatures reached the low to mid-90’s as afternoon and evening thunderstorms developed in the Upstate, and CoCoRaHS observers reported between a quarter and half an inch of precipitation in their 24-hour reports on Tuesday morning. As the front pushed through the Upstate, rainfall kept the maximum temperatures from climbing higher than the low 80’s. However, south of I-85, temperatures continued to be hot and humid, with highs in the mid-90’s and heat index values near 100 degrees. By the afternoon, widespread showers and thunderstorms pushed through the Midlands with strong winds and heavy rains. An RC-Winds station in Richland County reported a wind gust of 47 mph associated with the thunderstorms and the heavy rain caused nuisance flooding on low-lying roads around Columbia. The front and associated thunderstorms moved through the Lowcountry and Pee Dee by the evening, causing tree damage in Beaufort and Colleton counties, and lightning started a structural fire in Bluffton. CoCoRaHS observers in the Lowcountry, Midlands and Pee Dee reported widespread rainfall, with isolated areas measuring between two and three inches.
The cold front stalled offshore by Wednesday morning, and behind the front, a dry Canadian high pressure ushered unseasonably cooler weather with lower rain chances into the state through the rest of the week. The shift in the pattern provided fall-like temperatures, with reported minimum temperatures in the low to upper 60’s and maximum temperatures in the mid to upper 80’s, up to ten degrees below normal in some locations. On Wednesday, the NWS station at the Greenville-Spartanburg Airport tied the record low temperature of 60 degrees set back in 1966, and some locations in the Upstate observed lows in the upper 50’s. The NWS station at the Charleston International Airport reported a high temperature of 85 degrees on July 24, and the next morning the station tied the record minimum temperature of 68 degrees set in 1977. Many locations across the state reported one of their top five coolest July 25 mornings on record and temperatures rose into the mid-80’s by the afternoon.
Under mostly clear skies, and still under the influence of the dry Canadian high pressure, the cooler than normal low temperatures continued through the weekend. While the majority of the stations reported low temperatures in the mid-60’s to low 70’s during the remainder of the period, on Friday, July 26, the minimum temperature at the NWS station at Jocassee dropped to a chilly 48 degrees, breaking the previous record of 52 degrees from 2009. Maximum temperatures returned to near normal, with highs each day in the upper 80’s to low 90’s. No rain was reported during the weekend, though the moisture increased by late Sunday as the high shifted offshore, and southerly flow returned to the region the first part of the work week.
(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 | 0.01 | 24.46 | -1.0 |
| Greer Airport | 0.22 | 29.31 | 1.8 |
| Charlotte, NC Airport | 0.89 | 30.95 | 7.0 |
| Columbia Metro Airport | 1.25 | 23.63 | -2.4 |
| Orangeburg Airport | 0.49 | 16.83 | -10.8 |
| Augusta, GA Airport | 0.81 | 22.27 | -3.8 |
| Florence Airport | 1.19 | 22.42 | -2.3 |
| North Myrtle Beach Airport | 0.45 | 22.95 | -4.4 |
| Charleston Air Force Base | 0.71 | 24.41 | -3.5 |
| Savannah, GA Airport | 1.12 | 26.41 | -0.8 |
| *Weekly precipitation totals ending midnight Sunday. M - denotes total with missing values. |
4-inch depth soil temperature: Clinton: 75 degrees. Columbia: 82 degrees. Barnwell: 73 degrees. Mullins: 69 degrees.
Rainfall totals over the seven days varied greatly across the Palmetto State, with some localized areas receiving up to three inches of rain in Beaufort and Charleston counties in the Lowcountry, along with portions of Chesterfield, Marlboro and Williamsburg counties. Many locations in the Central Savannah River Area (CSRA) continued to miss out on the rain and received less than half an inch. River and stream levels remained below critical flood thresholds through the period. River levels in those areas that received rain on Tuesday and Wednesday rose slightly, while those parts of the state that received sparse rainfall observed low river levels. Similarly, streamflow values in areas that received the heaviest rainfall totals increased and remained slightly above normal. Streamflow values across much of the Lowcountry and southern Midlands were below normal through Sunday. Even though twenty to thirty inches of rain have fallen since the beginning of the year in the Midlands, portions of the Central Savannah River Area are close to ten inches below normal since January 1. Parts of the Lowcountry and Pee Dee continue to be the driest areas of the state, with less than twenty inches of rain for the year in areas from the Interstate 95 corridor to the coast, with isolated totals of over twenty-five inches in portions of Beaufort, Charleston and Colleton counties. In areas that have missed the beneficial rainfall, the totals are six to eight inches below normal for this time of year, with interior portions of Horry and Marion counties reporting totals nearly twelve inches below normal. Although rainfall totals in the Upstate over the last 30-days are below normal, the year-to-date rainfall totals in the Upstate remained near to above normal for this time of year, with more than twenty-five inches reported at many locations and over fifty inches in some of the more mountainous areas.
Charleston Harbor (CHTS1): 84.4 degrees.
Capers Nearshore Buoy (Station 41029): 80.4 degrees.
Fripps Nearshore Buoy (Station 41033): 83.3 degrees.
