Alert archive / South Carolina / Heat Advisories in 2021

Heat Advisory 2, NWS Charleston, SC

July 30, 2021Berkeley County, Colleton County, Dorchester County, South Carolina; Effingham County, Long County, Georgia

NWS Charleston, SC issued this heat advisory at Jul 30, 2021, 8:01 PM EDT for Berkeley County, Colleton County, Dorchester County, South Carolina; Effingham County, Long County, Georgia. It took effect at Jul 31, 2021, 11:00 AM EDT. It was in force for 9 hr.

The area

The counties it named.

The facts

Issued
Jul 30, 2021, 8:01 PM EDT (00:01 UTC)
In effect from
Jul 31, 2021, 11:00 AM EDT
Expired
Jul 31, 2021, 7:45 PM EDT
In force
9 hr
Issued by
NWS Charleston, SC

Counties Effingham County, GA, Long County, GA, Berkeley County, SC, Colleton County, SC, Dorchester County, SC

The radar

The Charleston,SC radar (KCLX), 21 km from the middle of the area, began a volume at 00:06 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Charleston AFB, SC (KCHS), launched 00:00Z, 0.0 hours before the alert went out and 82 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Charleston AFB, SC at 00:00Z on 2021-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3541 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Charleston AFB, SC at 00:00Z on 2021-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 112 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
3541 J/kg
Mixed-layer CIN
-18 J/kg
Mixed-layer LCL
931 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
112 m²/s²
0-3 km storm-relative helicity
86 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

556 
WWUS72 KCHS 310001
NPWCHS

URGENT - WEATHER MESSAGE
National Weather Service Charleston SC
801 PM EDT Fri Jul 30 2021

GAZ101-116>119-137>141-SCZ043>045-047>052-310815-
/O.NEW.KCHS.HT.Y.0002.210731T1600Z-210801T0000Z/
Effingham-Inland Bryan-Coastal Bryan-Inland Chatham-
Coastal Chatham-Long-Inland Liberty-Coastal Liberty-
Inland McIntosh-Coastal McIntosh-Inland Colleton-Dorchester-
Inland Berkeley-Inland Jasper-Beaufort-Coastal Colleton-
Charleston-Coastal Jasper-Tidal Berkeley-
Including the cities of Rincon, Springfield, Pembroke, 
Richmond Hill, Fort Mcallister, Oak Level, Garden City, Pooler, 
Savannah, Wilmington Island, Tybee Island, Ludowici, Hinesville, 
Fort Stewart, Townsend, Darien, Walterboro, Saint George, 
Summerville, Goose Creek, Moncks Corner, Ridgeland, Beaufort, 
Hilton Head Island, Edisto Beach, Charleston, North Charleston, 
Mount Pleasant, Levy, Chelsea, Jasper, and Daniel Island
801 PM EDT Fri Jul 30 2021

...HEAT ADVISORY IN EFFECT FROM NOON TO 8 PM EDT SATURDAY...

* WHAT...Heat index values up to 111 expected.

* WHERE...Portions of southeast South Carolina and southeast 
  Georgia.

* WHEN...From noon to 8 PM EDT Saturday.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sunshine, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$
7 follow-up statements
991 
WWUS72 KCHS 310423
NPWCHS

URGENT - WEATHER MESSAGE
National Weather Service Charleston SC
1223 AM EDT Sat Jul 31 2021

GAZ101-116>119-137>141-SCZ043>045-047>052-311230-
/O.CON.KCHS.HT.Y.0002.210731T1600Z-210801T0000Z/
Effingham-Inland Bryan-Coastal Bryan-Inland Chatham-
Coastal Chatham-Long-Inland Liberty-Coastal Liberty-
Inland McIntosh-Coastal McIntosh-Inland Colleton-Dorchester-
Inland Berkeley-Inland Jasper-Beaufort-Coastal Colleton-
Charleston-Coastal Jasper-Tidal Berkeley-
Including the cities of Rincon, Springfield, Pembroke, 
Richmond Hill, Fort Mcallister, Oak Level, Garden City, Pooler, 
Savannah, Wilmington Island, Tybee Island, Ludowici, Hinesville, 
Fort Stewart, Townsend, Darien, Walterboro, Saint George, 
Summerville, Goose Creek, Moncks Corner, Ridgeland, Beaufort, 
Hilton Head Island, Edisto Beach, Charleston, North Charleston, 
Mount Pleasant, Levy, Chelsea, Jasper, and Daniel Island
1223 AM EDT Sat Jul 31 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM NOON TODAY TO 8 PM EDT
THIS EVENING...

* WHAT...Heat index values up to 111 expected.

* WHERE...Portions of Southeast South Carolina and Southeast 
  Georgia.

* WHEN...From noon today to 8 PM EDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sunshine, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$
302 
WWUS72 KCHS 310723
NPWCHS

URGENT - WEATHER MESSAGE
National Weather Service Charleston SC
323 AM EDT Sat Jul 31 2021

GAZ101-116>119-137>141-SCZ043>045-047>052-311530-
/O.EXT.KCHS.HT.Y.0002.210731T1500Z-210801T0000Z/
Effingham-Inland Bryan-Coastal Bryan-Inland Chatham-
Coastal Chatham-Long-Inland Liberty-Coastal Liberty-
Inland McIntosh-Coastal McIntosh-Inland Colleton-Dorchester-
Inland Berkeley-Inland Jasper-Beaufort-Coastal Colleton-
Charleston-Coastal Jasper-Tidal Berkeley-
Including the cities of Rincon, Springfield, Pembroke, 
Richmond Hill, Fort Mcallister, Oak Level, Garden City, Pooler, 
Savannah, Wilmington Island, Tybee Island, Ludowici, Hinesville, 
Fort Stewart, Townsend, Darien, Walterboro, Saint George, 
Summerville, Goose Creek, Moncks Corner, Ridgeland, Beaufort, 
Hilton Head Island, Edisto Beach, Charleston, North Charleston, 
Mount Pleasant, Levy, Chelsea, Jasper, and Daniel Island
323 AM EDT Sat Jul 31 2021

...HEAT ADVISORY NOW IN EFFECT FROM 11 AM THIS MORNING TO 8 PM
EDT THIS EVENING...

* WHAT...Heat index values 110 to 113 possible.

* WHERE...Portions of Southeast South Carolina and Southeast
  Georgia, mainly along and east of I-95. This includes the
  Charleston and Savannah Metro Areas.

* WHEN...From 11 AM this morning to 8 PM EDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

* ADDITIONAL DETAILS...Isolated to scattered afternoon
  thunderstorms could bring relief to some locations during the
  afternoon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sunshine, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$
685 
WWUS72 KCHS 311003
NPWCHS

URGENT - WEATHER MESSAGE
National Weather Service Charleston SC
603 AM EDT Sat Jul 31 2021

GAZ101-116>119-137>141-SCZ043>045-047>052-311815-
/O.CON.KCHS.HT.Y.0002.210731T1500Z-210801T0000Z/
Effingham-Inland Bryan-Coastal Bryan-Inland Chatham-
Coastal Chatham-Long-Inland Liberty-Coastal Liberty-
Inland McIntosh-Coastal McIntosh-Inland Colleton-Dorchester-
Inland Berkeley-Inland Jasper-Beaufort-Coastal Colleton-
Charleston-Coastal Jasper-Tidal Berkeley-
Including the cities of Rincon, Springfield, Pembroke, 
Richmond Hill, Fort Mcallister, Oak Level, Garden City, Pooler, 
Savannah, Wilmington Island, Tybee Island, Ludowici, Hinesville, 
Fort Stewart, Townsend, Darien, Walterboro, Saint George, 
Summerville, Goose Creek, Moncks Corner, Ridgeland, Beaufort, 
Hilton Head Island, Edisto Beach, Charleston, North Charleston, 
Mount Pleasant, Levy, Chelsea, Jasper, and Daniel Island
603 AM EDT Sat Jul 31 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM 11 AM THIS MORNING TO
8 PM EDT THIS EVENING...

* WHAT...Heat index values 110 to 113 possible.

* WHERE...Portions of Southeast South Carolina and Southeast 
  Georgia, mainly along and east of I-95. This includes the 
  Charleston and Savannah Metro Areas.

* WHEN...From 11 AM this morning to 8 PM EDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

* ADDITIONAL DETAILS...Isolated to scattered afternoon 
  thunderstorms could bring relief to some locations during the 
  afternoon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sunshine, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$
334 
WWUS72 KCHS 311344
NPWCHS

URGENT - WEATHER MESSAGE
National Weather Service Charleston SC
944 AM EDT Sat Jul 31 2021

GAZ101-116>119-137>141-SCZ043>045-047>052-312145-
/O.CON.KCHS.HT.Y.0002.210731T1500Z-210801T0000Z/
Effingham-Inland Bryan-Coastal Bryan-Inland Chatham-
Coastal Chatham-Long-Inland Liberty-Coastal Liberty-
Inland McIntosh-Coastal McIntosh-Inland Colleton-Dorchester-
Inland Berkeley-Inland Jasper-Beaufort-Coastal Colleton-
Charleston-Coastal Jasper-Tidal Berkeley-
Including the cities of Rincon, Springfield, Pembroke, 
Richmond Hill, Fort Mcallister, Oak Level, Garden City, Pooler, 
Savannah, Wilmington Island, Tybee Island, Ludowici, Hinesville, 
Fort Stewart, Townsend, Darien, Walterboro, Saint George, 
Summerville, Goose Creek, Moncks Corner, Ridgeland, Beaufort, 
Hilton Head Island, Edisto Beach, Charleston, North Charleston, 
Mount Pleasant, Levy, Chelsea, Jasper, and Daniel Island
944 AM EDT Sat Jul 31 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT THIS EVENING...

* WHAT...Heat index values up to 113 expected.

* WHERE...Portions of southeast South Carolina and southeast
  Georgia, mainly along and east of I-95, including the
  Charleston, Beaufort and Savannah areas.

* WHEN...Until 8 PM EDT this evening, with the worst conditions
  generally from around 1 to 5 PM.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

* ADDITIONAL DETAILS...Isolated to scattered afternoon
  thunderstorms could bring relief to some locations during the
  afternoon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sunshine, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$
163 
WWUS72 KCHS 311920
NPWCHS

URGENT - WEATHER MESSAGE
National Weather Service Charleston SC
320 PM EDT Sat Jul 31 2021

GAZ101-116>119-137>141-SCZ043>045-047>052-010000-
/O.CON.KCHS.HT.Y.0002.000000T0000Z-210801T0000Z/
Effingham-Inland Bryan-Coastal Bryan-Inland Chatham-
Coastal Chatham-Long-Inland Liberty-Coastal Liberty-
Inland McIntosh-Coastal McIntosh-Inland Colleton-Dorchester-
Inland Berkeley-Inland Jasper-Beaufort-Coastal Colleton-
Charleston-Coastal Jasper-Tidal Berkeley-
Including the cities of Rincon, Springfield, Pembroke, 
Richmond Hill, Fort Mcallister, Oak Level, Garden City, Pooler, 
Savannah, Wilmington Island, Tybee Island, Ludowici, Hinesville, 
Fort Stewart, Townsend, Darien, Walterboro, Saint George, 
Summerville, Goose Creek, Moncks Corner, Ridgeland, Beaufort, 
Hilton Head Island, Edisto Beach, Charleston, North Charleston, 
Mount Pleasant, Levy, Chelsea, Jasper, and Daniel Island
320 PM EDT Sat Jul 31 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT THIS EVENING...

* WHAT...Heat index values up to 114.

* WHERE...Portions of southeast South Carolina and southeast
  Georgia, mainly along and east of I-95, including the 
  Charleston, Beaufort and Savannah areas.

* WHEN...Until 8 PM EDT this evening, with the worst conditions
  until about 5 PM.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

* ADDITIONAL DETAILS...Isolated to scattered showers and storms
  will bring relief to some locations.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sunshine, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$
818 
WWUS72 KCHS 312129
NPWCHS

URGENT - WEATHER MESSAGE
National Weather Service Charleston SC
529 PM EDT Sat Jul 31 2021

SCZ043>045-049-050-052-312230-
/O.CAN.KCHS.HT.Y.0002.000000T0000Z-210801T0000Z/
Inland Colleton-Dorchester-Inland Berkeley-Coastal Colleton-
Charleston-Tidal Berkeley-
Including the cities of Walterboro, Saint George, Summerville, 
Goose Creek, Moncks Corner, Edisto Beach, Charleston, 
North Charleston, Mount Pleasant, and Daniel Island
529 PM EDT Sat Jul 31 2021

...HEAT ADVISORY IS CANCELLED...

Showers and thunderstorms have reduced the coverage of heat
indices of 110 degrees or greater. 

$$

GAZ101-116>119-137>141-SCZ047-048-051-010000-
/O.CON.KCHS.HT.Y.0002.000000T0000Z-210801T0000Z/
Effingham-Inland Bryan-Coastal Bryan-Inland Chatham-
Coastal Chatham-Long-Inland Liberty-Coastal Liberty-
Inland McIntosh-Coastal McIntosh-Inland Jasper-Beaufort-
Coastal Jasper-
Including the cities of Rincon, Springfield, Pembroke, 
Richmond Hill, Fort Mcallister, Oak Level, Garden City, Pooler, 
Savannah, Wilmington Island, Tybee Island, Ludowici, Hinesville, 
Fort Stewart, Townsend, Darien, Ridgeland, Beaufort, 
Hilton Head Island, Levy, Chelsea, and Jasper
529 PM EDT Sat Jul 31 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT THIS EVENING...

* WHAT...Heat index values up to 113.

* WHERE...Portions of southeast South Carolina and southeast
  Georgia, mainly along and east of I-95, including the 
  Charleston, Beaufort and Savannah areas.

* WHEN...Until 8 PM EDT this evening, with the worst conditions
  early this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

* ADDITIONAL DETAILS...Isolated to scattered showers and storms 
  will bring relief to some locations.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sunshine, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$
704 
WWUS72 KCHS 312345
NPWCHS

URGENT - WEATHER MESSAGE
National Weather Service Charleston SC
745 PM EDT Sat Jul 31 2021

GAZ101-116>119-137>141-SCZ047-048-051-010045-
/O.CAN.KCHS.HT.Y.0002.000000T0000Z-210801T0000Z/
Effingham-Inland Bryan-Coastal Bryan-Inland Chatham-
Coastal Chatham-Long-Inland Liberty-Coastal Liberty-
Inland McIntosh-Coastal McIntosh-Inland Jasper-Beaufort-
Coastal Jasper-
Including the cities of Rincon, Springfield, Pembroke, 
Richmond Hill, Fort Mcallister, Oak Level, Garden City, Pooler, 
Savannah, Wilmington Island, Tybee Island, Ludowici, Hinesville, 
Fort Stewart, Townsend, Darien, Ridgeland, Beaufort, 
Hilton Head Island, Levy, Chelsea, and Jasper
745 PM EDT Sat Jul 31 2021

...HEAT ADVISORY IS CANCELLED...

$$

The office that day

Everything else NWS Charleston, SC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 31, 3:25 PM EDTSpecial Weather StatementCHSCharleston35 min
Jul 31, 3:50 PM EDTAreal Flood AdvisoryCHSBerkeley, Charleston115 min
Jul 31, 4:00 PM EDTSpecial Weather StatementCHSBerkeley30 min
Jul 31, 4:01 PM EDTSmall Craft AdvisoryCHS32 hr
Jul 31, 4:06 PM EDTSpecial Weather StatementCHSBerkeley24 min
Jul 31, 4:29 PM EDTSpecial Weather StatementCHSColleton31 min
Jul 31, 4:38 PM EDTSpecial Weather StatementCHSCharleston37 min
Jul 31, 4:51 PM EDTSpecial Marine WarningCHS57 min
Jul 31, 4:53 PM EDTSpecial Weather StatementCHSCharleston37 min
Jul 31, 5:04 PM EDTSevere Thunderstorm WarningCHSBerkeley, Charleston34 min
Jul 31, 5:11 PM EDTAreal Flood AdvisoryCHSBerkeley, Charleston36 min
Jul 31, 5:26 PM EDTSpecial Weather StatementCHSBerkeley34 min
Jul 31, 5:37 PM EDTSpecial Weather StatementCHSColleton23 min
Jul 31, 5:59 PM EDTSpecial Weather StatementCHSColleton31 min
Jul 31, 6:02 PM EDTSpecial Weather StatementCHSBerkeley28 min
Jul 31, 6:38 PM EDTSpecial Weather StatementCHSBerkeley37 min
Jul 31, 6:46 PM EDTSpecial Weather StatementCHSDorchester29 min

Nearby

Heat Advisories in South Carolina, 2021Heat Advisories in Georgia, 2021Every heat advisory in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.