The main weather story for the period was the warmer-than-normal temperatures and high heat index values. On Monday, hot and humid conditions prevailed, with maximum temperatures in the mid to upper 90s. A weak backdoor cold front triggered isolated showers and thunderstorms on Monday and into early Tuesday. It pushed through the region, and a slightly drier airmass was in place on Tuesday; however, highs were still up to five degrees above normal, with temperatures in the mid- to upper 90s. High pressure started to build over the region, providing increasing heat and humidity headed into the first part of July and lasting through the holiday weekend.
Low temperatures in the Upstate were up to ten degrees above normal on Wednesday, and the National Weather Service (NWS) at Caesars Head reported a new record-high minimum temperature of 71 degrees, breaking the previous record of 69 degrees set in 1981. The NWS at the Greenville-Spartanburg International Airport (GSP) also set a new record high minimum temperature on Wednesday of 75 degrees, breaking the previous record of 75 degrees set in 2019. Maximum temperatures across the state reached the upper 90s to over 100 degrees through Sunday. On Thursday, the NWS GSP tied the daily record high of 99 degrees set in 1996, and heat index values exceeded 105 degrees in parts of the Upstate. Along the coast, the Myrtle Beach Surf Rescue reported four rip current rescues that afternoon. The hot temperatures and high humidity resulted in heat index values over 100 degrees, with some areas of the state recording values between 105 and 110 degrees. Heat advisories were issued for most of the state, as the combination of high temperatures and heat index values increased the risk of heat-related illness for those spending time outdoors during the holiday weekend.
A persistent weak boundary over the Upstate served as the focus for some strong to severe thunderstorms late Thursday afternoon. These storms caused wind damage, primarily downed trees, in Oconee, McCormick, Abbeville, Greenwood, Anderson, Greenville, Pickens, and Spartanburg counties. A storm spotter near Berea in Greenville County reported penny-sized hail, and another spotter near Fair Play in Oconee County observed golf-ball-sized hail. The sea breeze helped trigger additional strong thunderstorms early Sunday afternoon, which caused wind damage in portions of Charleston, Clarendon, Dorchester, and Orangeburg counties. The NWS station at the Charleston International Airport recorded a 52 mph wind gust associated with these storms.
(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 | 0.12 | 19.72 | -4.8 |
| Greer Airport | 0.84 | 18.89 | -6.2 |
| Charlotte, NC Airport | Trace | 15.09 | -7.2 |
| Columbia Metro Airport | 0.03 | 15.65 | -6.9 |
| Orangeburg 2 (COOP) | M | 16.22 | -9.2 |
| Augusta, GA Airport | 0.25 | 20.29 | -2.7 |
| Florence Airport | Trace | 16.46 | -5.0 |
| North Myrtle Beach Airport | 0.00 | 8.15 | -12.3 | Charleston Air Force Base | 0.57 | 11.58 | -12.1 |
| Savannah, GA Airport | Trace | 10.91 | -13.3 |
| *Weekly precipitation totals ending midnight Sunday. M - denotes total with missing values. s - denotes total with suspect data. |
4-inch depth soil temperature: Columbia: 82 degrees. Barnwell: 78 degrees. Mullins: 77 degrees.
Due to the scattered, isolated nature of the showers and thunderstorms during the period, rainfall totals varied widely across the state. Portions of the Lower Savannah River Basin and Lowcountry recorded no rain, while a few locations in Anderson, Calhoun, Laurens, and Spartanburg counties reported just over an inch of rain. With warmer-than-normal temperatures and limited precipitation reported over the past few periods, the U.S. Drought Monitor map released on Thursday, July 2, showed expansion of severe drought (D2) conditions in parts of the Lowcountry and Midlands. Despite rainfall in previous periods, drought conditions persist across the state.
Values for the 14-day average streamflow are no longer available because some USGS products have been decommissioned. Information on current streamflow is available at https://waterdata.usgs.gov/state/South%20Carolina/. River and coastal tidal heights remained below flood stage throughout the entire period.
