A cluster of thunderstorms developed across portions of southeast South Carolina in the late afternoon and produced large hail and damaging wind gusts.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS CHS wrote it up.
A cluster of thunderstorms developed across portions of southeast South Carolina in the late afternoon and produced large hail and damaging wind gusts.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Charleston, SC wrote its last area forecast discussion before the first event at May 4, 3:29 PM EST, 4 minutes earlier.
Area Forecast Discussion National Weather Service Charleston SC 429 PM EDT Tue May 4 2021 .SYNOPSIS... High pressure will extend across the region through tonight. A series of upper level disturbances could bring unsettled weather through Wednesday, followed by a cold front Wednesday night into Thursday. Dry high pressure is then expected to prevail for the weekend. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... This Evening and Tonight: Aloft, a southwest flow will prevail between a large ridge of high pressure centered to the south and offshore and a low pressure trough advancing through the Midwest. At the sfc, southwest winds are expected along the western edge of Atlantic high pressure and well ahead of a cold front advancing east of the lower Mississippi River Valley. Warm and moisture conditions will prevail across the region well in advance of the approaching front, which will continue to support gusty winds upwards to around 20 mph at times across the local area. The main forecast challenge continues to be timing and coverage of convection/precip heading into this evening, especially since the bulk of synoptic forcing features remain west of the area through tonight. However, given the amount of sfc heating and moisture in place (PWATs around 1.5 inches), we should continue to experience few to scattered showers and thunderstorms across the area during the next couple hours, a few of which could produce strong and/or damaging wind gusts along with small hail. However, severe thunderstorm activity should remain isolated during the next couple hours. Heading into the sunset, the main concern will likely come from convection that continues to develop upstream and gradually advects into the area from the west-northwest. SBCAPE between 1500- 2500 J/kg and 0-6 km bulk shear between 30-35 kt could support a few strong and/or severe thunderstorms, especially across inland most locations where activity has a better chance of reaching locations within a few hours of sunset (also noted by SPC's latest Day 1 Convective Outlook with a Slight Risk). Unidirectional flow and poor mid-lvl lapse rates suggest the main threat from stronger and/or severe thunderstorms to be damaging wind gusts, especially if mesoscale boundary collisions and/or cold pooling associated with clusters of thunderstorms upstream result in outflow surging forward into and across the area this evening. Latest guidance suggests any cluster and/or line of showers/thunderstorms struggling to reach coastal areas overnight as instability wanes. Mild conditions overnight should favor lows in the upper 60s to low 70s, though these values could be altered by convective related cooling. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/... Wednesday: The mid-levels will consist of troughing to our north, with nearly zonal flow over our area. Weak disturbances embedded in the flow should pass mostly to our north, especially from late afternoon into the overnight hours. At the surface, a cold front will approach from the west during the day. The front is expected to cross through our region around midnight, then move offshore. A deep plume of moisture is ahead of the front, with PWATs possibly getting as high as 1.75-2.0". The main concern continues to be the severe potential in the afternoon and evening. Temperatures ahead of the front are forecasted to get into the 80s. Instability is lacking. MLCAPEs may struggle to get into the 500-1,000 J/kg range. There isn't a lot of shear either, with 0-6 km bulk shear values peaking around 35-40 kt. But the overall potential for severe thunderstorms remains. For that reason, SPC continues to have our area under a Marginal Risk, with the main threats being damaging winds and hail. This remains reasonable and will be adjusted with the upcoming forecasts to better refine things during the afternoon and evening hours. There's also a small risk that storm training could cause localized flooding, especially in areas that have received abundant rain the past few days. Finally, there could be gusty winds ahead of the front, especially across Lake Moultrie. The convection should wind down from west to east as the front moves through. Lows should be a few degrees above normal. Thursday: The mid-level trough over the East Coast will become more amplified, causing heights to drop over our area. The surface cold front will be offshore in the morning, slowly moving away with time. Meanwhile, high pressure will build into our area from the west with time. The highest PWATs will remain confined to our far southern counties in the morning. This is where models have remnant showers and maybe some thunderstorms. However, they will get pushed offshore into the afternoon as the dry high pressure builds in. Most locations far inland and across our SC counties may stay dry all day. Though, all locations will be dry at night as the high takes hold. Despite us being on the cooler side of the front, models still point to highs near normal. The same can be said about the lows. && .LONG TERM /FRIDAY THROUGH TUESDAY/... Both the WPC and NBM keep our area dry as high pressure moves across the Southeast through the weekend. Temperatures will rise above normal during this time period. The NBM has increasing POPs Monday and Tuesday, as WPC forecasts a front approaching from the west. && .AVIATION /21Z TUESDAY THROUGH SUNDAY/... Tempo MVFR conditions are possible due to thunderstorms at the CHS terminal through 21Z. Otherwise, VFR conditions are expected for the next few hours at both CHS and SAV terminals, before the potential of showers and/or thunderstorms arrive this evening. Confidence remains high enough to maintain prevailing VCTS and a TEMPO group for TSRA during 01Z-04Z at CHS and 01Z- 05Z at SAV. However, better refinements will likely need to be made late afternoon as convective trends/timing become more clear. Southwest winds will be breezy at both sites this afternoon, with frequent gusts up to around 15-20 knots. Extended Aviation Outlook: There is a low probability for flight restrictions in showers/thunderstorms through Wednesday night. Additionally, winds could be gusty Wednesday. Otherwise, VFR. && .MARINE... This Evening and Tonight: South-southwest flow will prevail across local waters through tonight between high pressure extending across the western Atlantic and a cold front approaching the region, but remaining well inland. Winds are expected to gust upwards to 15-20 kt across most waters, although the pattern could be disrupted by inland thunderstorms reaching the coast and shifting offshore. A few stronger and/or severe thunderstorms can not be ruled out late evening into early overnight hours. Seas should build to 2-4 ft with some 5 ft seas possible around 20 nm off the Charleston County coast and across offshore Georgia waters. Wednesday: A cold front will approach the region from the west, bringing elevated winds and seas. The front is expected to move through Wednesday night, causing winds to veer and then ease. Conditions are expected below Small Craft Advisory criteria. Thursday: The front will initially be offshore in the morning, gradually moving away as high pressure builds in from the west. Winds will clock around with time, increasing during the overnight hours as the pressure grading becomes enhanced. Gusts could approach 25 kt for the outer GA waters late, but at this time no Small Craft Advisories are expected. Friday into the Weekend: High pressure will prevail across the region. Winds and seas are expected to remain low enough that no marine headlines are expected. && .FIRE WEATHER... Friday, west-northwest winds could gust into the 20-25 mph range, and afternoon relative humidity values could drop to 25-30%. Showers/thunderstorms over some areas the next few days should raise fuel moistures, which could limit the overall fire danger. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && NEAR TERM...DPB SHORT TERM... LONG TERM... AVIATION...DPB MARINE...DPB FIRE WEATHER...
Hazardous Weather Outlook National Weather Service Charleston SC 333 AM EDT Tue May 4 2021 GAZ087-088-099>101-114>119-137>141-SCZ040-042>045-047>052-050745- Jenkins-Screven-Candler-Bulloch-Effingham-Tattnall-Evans- Inland Bryan-Coastal Bryan-Inland Chatham-Coastal Chatham-Long- Inland Liberty-Coastal Liberty-Inland McIntosh-Coastal McIntosh- Allendale-Hampton-Inland Colleton-Dorchester-Inland Berkeley- Inland Jasper-Beaufort-Coastal Colleton-Charleston-Coastal Jasper- Tidal Berkeley- 333 AM EDT Tue May 4 2021 This Hazardous Weather Outlook is for southeast Georgia and southeast South Carolina. .DAY ONE...Today and tonight. Severe Thunderstorms: Thunderstorms are expected to develop west of the region this afternoon and could move into southeast Georgia and southeast South Carolina late this afternoon and this evening. The primary severe weather threat will be damaging wind gusts. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Severe Thunderstorms: Isolated thunderstorms could develop on Wednesday, possibly producing damaging wind gusts and large hail during the afternoon and early evening hours. .SPOTTER INFORMATION STATEMENT... Spotter assistance is not anticipated at this time. AMZ330-350-352-354-374-050745- Charleston Harbor- Waters from South Santee River to Edisto Beach SC out 20 NM- Waters from Edisto Beach SC to Savannah GA out 20 NM- Waters from Savannah GA to Altamaha Sound GA out 20 NM, including Grays Reef National Marine Sanctuary- Waters from Savannah GA to Altamaha Sound GA from 20 to 60 NM- 333 AM EDT Tue May 4 2021 This Hazardous Weather Outlook is for Atlantic coastal waters. .DAY ONE...Today and tonight. Severe Thunderstorms: Thunderstorms are expected to impact inland locations this afternoon and could move into the Atlantic coastal waters this evening. The primary severe weather threat will be strong wind gusts. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotter assistance is not anticipated at this time.
Special Weather Statement
National Weather Service Charleston SC
338 PM EDT Tue May 4 2021
SCZ050-042015-
Charleston-
338 PM EDT Tue May 4 2021
...STRONG THUNDERSTORMS WILL IMPACT PORTIONS OF CHARLESTON COUNTY...
At 338 PM EDT, National Weather Service doppler radar indicated a
strong thunderstorm over Hollywood, or 9 miles west of Johns Island,
moving east at 25 mph.
HAZARD...strong winds 45 to 55 mph and up to penny sized hail.
SOURCE...Radar Indicated.
IMPACT...Expect minor damage to tree limbs and blowing around of
light, unsecured objects. Minor hail damage to plants,
trees and crops is possible. Damage to windshields is
unlikely.
Some locations in the path of this storm include...
Johns Island, West Ashley, Hollywood, Ravenel, Meggett, Yonges Island
and Wadmalaw Island.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Cloud to ground lightning is occurring. Avoid using metal equipment
and keep distance from objects such as irrigation systems, poles,
fences and trees. Livestock and outdoor pets are particularly
vulnerable in open fields and should be taken into shelters if time
permits.
&&
LAT...LON 3265 8030 3276 8033 3283 8010 3270 8006
TIME...MOT...LOC 1938Z 254DEG 20KT 3274 8023
MAX HAIL SIZE...0.75 IN
MAX WIND GUST...55 MPHSpecial Weather Statement
National Weather Service Charleston SC
408 PM EDT Tue May 4 2021
SCZ045-050-052-042045-
Inland Berkeley-Tidal Berkeley-Charleston-
408 PM EDT Tue May 4 2021
...STRONG THUNDERSTORMS WILL IMPACT PORTIONS OF CHARLESTON AND
BERKELEY COUNTIES...
At 408 PM EDT, National Weather Service doppler radar indicated
strong thunderstorms along a line extending from Sangaree to Hanahan,
and moving northeast at 25 mph.
HAZARD...strong winds 45 to 55 mph and up to penny sized hail.
SOURCE...Radar Indicated.
IMPACT...Expect minor damage to tree limbs and blowing around of
light, unsecured objects. Minor hail damage to plants,
trees and crops is possible. Damage to windshields is
unlikely.
Some locations in the path of these storms include...
North Charleston, Summerville, Goose Creek, Hanahan, Naval Weapons
Station Charleston, Ladson, Daniel Island and Sangaree.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Report damage directly to the Charleston National Weather Service at
888-383-2024 when it is safe to do so. You can also email your
report to nws.charlestonsc@noaa.gov.
&&
LAT...LON 3298 7979 3288 7997 3298 8014 3298 8011
3300 8013 3299 8015 3301 8018 3302 8015
3304 8018 3314 8004
TIME...MOT...LOC 2008Z 235DEG 21KT 3302 8014 3293 7998
MAX HAIL SIZE...0.75 IN
MAX WIND GUST...55 MPHSpecial Weather Statement
National Weather Service Charleston SC
432 PM EDT Tue May 4 2021
SCZ043-044-050-042100-
Charleston-Inland Colleton-Dorchester-
432 PM EDT Tue May 4 2021
...STRONG THUNDERSTORMS WILL IMPACT PORTIONS OF CHARLESTON, COLLETON
AND DORCHESTER COUNTIES...
At 432 PM EDT, National Weather Service doppler radar indicated a
strong thunderstorm near Givhans, or near Givhans Ferry State Park,
moving east at 30 mph.
HAZARD...strong winds 45 to 55 mph and up to penny sized hail.
SOURCE...Radar Indicated.
IMPACT...Expect minor damage to tree limbs and blowing around of
light, unsecured objects. Minor hail damage to plants,
trees and crops is possible. Damage to windshields is
unlikely.
Some locations in the path of this storm include...
North Charleston, Summerville, Goose Creek, Hanahan, Givhans Ferry
State Park, Ladson, Ridgeville and Givhans.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Report damage directly to the Charleston National Weather Service at
888-383-2024 when it is safe to do so. You can also email your
report to nws.charlestonsc@noaa.gov.
&&
LAT...LON 3302 8014 3300 8011 3300 8010 3299 8010
3300 8005 3298 8004 3295 8004 3292 8002
3288 8038 3303 8047 3311 8026
TIME...MOT...LOC 2032Z 252DEG 24KT 3297 8036
MAX HAIL SIZE...0.75 IN
MAX WIND GUST...55 MPHThe Charleston,SC radar (KCLX), 123 km away, was scanning. The volume nearest the first event began at 20:33 UTC.
13 thunderstorm wind, 1 hail. Local standard time, as filed.
A local news station relayed a report of quarter to half dollar sized hail near Huger via social media.
A tree was reported down and in the roadway at Wee Hope Loop and Bonnie Doon Road.
A tree was reported down and blocking the roadway at Bad Ham Lane and Lowcountry Highway.
A tree was reported down in the roadway at Tabor Road and Bells Highway.
A tree was reported down and in the roadway at Peirce Road and Rhode Drive.
A tree was reported down and in the roadway at Peirce Road and Whites Avenue.
A tree was reported down and in the roadway at Industrial Road and Highway 15.
A tree was reported down and in the roadway at Cougar Nation Drive and Jefferies Highway.
Colleton County Emergency Management reported a tree down at Jefferies Highway and Lakeshore Drive.
Colleton County Emergency Management reported a tree down at Pleasant Grove Road and Maple Ridge Road.
A tree was reported down and in the roadway at Highway 15 and Robertson Boulevard.
A tree was reported down and in the roadway at Welch Creek and Coolers Dairy Road. A vehicle collided with the downed tree, but there were no known injuries.
A tree was reported down and in the roadway at Round O Road and Fennel Drive.
A tree was reported down and in the roadway at Rehoboth Road and Muckenfus Road.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in South Carolina in 2021Every state in 2021This day in weather historyWarnings in South Carolina, May 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 959021, 959022, 959023, 959024, 959025, 959026, 959027, 959034, 959028, 959029, 959030, 959033, 959031, 959032.