Alert archive / North Carolina / Heat Advisories in 2021

Heat Advisory 2, NWS Wilmington, NC

July 31, 20214 counties in North Carolina; 4 counties in South Carolina

NWS Wilmington, NC issued this heat advisory at Jul 31, 2021, 3:13 AM EDT for 4 counties in North Carolina; 4 counties in South Carolina. It took effect at Jul 31, 2021, 11:00 AM EDT. It was in force for 8 hr.

The area

The counties it named.

The facts

Issued
Jul 31, 2021, 3:13 AM EDT (07:13 UTC)
In effect from
Jul 31, 2021, 11:00 AM EDT
Expired
Jul 31, 2021, 7:00 PM EDT
In force
8 hr
Issued by
NWS Wilmington, NC

Counties Brunswick County, NC, Columbus County, NC, New Hanover County, NC, Pender County, NC, Georgetown County, SC, Horry County, SC, Marion County, SC, Williamsburg County, SC

The radar

The Wilmington radar (KLTX), 30 km from the middle of the area, began a volume at 07:15 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, 7.2 hours before the alert went out and 169 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.

733 
WWUS72 KILM 310713
NPWILM

URGENT - WEATHER MESSAGE
National Weather Service Wilmington NC
313 AM EDT Sat Jul 31 2021

NCZ099-109-110-SCZ054>056-058-059-311515-
/O.NEW.KILM.HT.Y.0002.210731T1500Z-210731T2300Z/
Columbus-Inland Brunswick-Coastal Brunswick-Coastal Horry-
Inland Georgetown-Coastal Georgetown-Central Horry-Northern Horry-
Including the cities of Whiteville, Tabor City, Chadbourn, 
Lake Waccamaw, Boiling Spring Lakes, Leland, Shallotte, 
Oak Island, Long Beach, Southport, Sunset Beach, Myrtle Beach, 
Socastee, North Myrtle Beach, Garden City, Little River, Andrews,
Georgetown, Murrells Inlet, Conway, Longs, Bucksport, Loris, 
Green Sea, and Aynor
313 AM EDT Sat Jul 31 2021

...HEAT ADVISORY IN EFFECT FROM 11 AM THIS MORNING TO 7 PM EDT
THIS EVENING...

* WHAT...Heat index values up to 107 expected.

* WHERE...In South Carolina, Coastal Horry, Inland Georgetown, 
  Coastal Georgetown, Central Horry and Northern Horry Counties. 
  In North Carolina, Columbus, Inland Brunswick and Coastal 
  Brunswick Counties.

* WHEN...From 11 AM this morning to 7 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 sun, 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.

&&

$$
2 follow-up statements
213 
WWUS72 KILM 311345
NPWILM

URGENT - WEATHER MESSAGE
National Weather Service Wilmington NC
945 AM EDT Sat Jul 31 2021

NCZ105>108-SCZ033-039-312300-
/O.EXA.KILM.HT.Y.0002.210731T1500Z-210731T2300Z/
Inland Pender-Coastal Pender-Inland New Hanover-
Coastal New Hanover-Marion-Williamsburg-
Including the cities of Burgaw, Surf City, Wilmington, Masonboro,
Myrtle Grove, Ogden, Carolina Beach, Seagate, Marion, Mullins, 
and Kingstree
945 AM EDT Sat Jul 31 2021

...HEAT ADVISORY IN EFFECT UNTIL 7 PM EDT THIS EVENING...

* WHAT...Heat index values up to 106 expected.

* WHERE...In South Carolina, Marion and Williamsburg Counties. 
  In North Carolina, Inland Pender, Coastal Pender, Inland New 
  Hanover and Coastal New Hanover Counties.

* WHEN...From 11 AM this morning to 7 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 sun, 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.

&&

$$

NCZ099-109-110-SCZ054>056-058-059-312300-
/O.CON.KILM.HT.Y.0002.210731T1500Z-210731T2300Z/
Columbus-Inland Brunswick-Coastal Brunswick-Coastal Horry-
Inland Georgetown-Coastal Georgetown-Central Horry-Northern Horry-
Including the cities of Whiteville, Tabor City, Chadbourn, 
Lake Waccamaw, Boiling Spring Lakes, Leland, Shallotte, 
Oak Island, Long Beach, Southport, Sunset Beach, Myrtle Beach, 
Socastee, North Myrtle Beach, Garden City, Little River, Andrews,
Georgetown, Murrells Inlet, Conway, Longs, Bucksport, Loris, 
Green Sea, and Aynor
945 AM EDT Sat Jul 31 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 PM EDT THIS EVENING...

* WHAT...Heat index values up to 107 expected.

* WHERE...In South Carolina, Coastal Horry, Inland Georgetown, 
  Coastal Georgetown, Central Horry and Northern Horry Counties. 
  In North Carolina, Columbus, Inland Brunswick and Coastal 
  Brunswick Counties.

* WHEN...From 11 AM this morning to 7 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 sun, 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.

&&

$$
885 
WWUS72 KILM 312301
NPWILM

URGENT - WEATHER MESSAGE
National Weather Service Wilmington NC
701 PM EDT Sat Jul 31 2021

NCZ099-105>110-SCZ033-039-054>056-058-059-010015-
/O.EXP.KILM.HT.Y.0002.000000T0000Z-210731T2300Z/
Columbus-Inland Pender-Coastal Pender-Inland New Hanover-
Coastal New Hanover-Inland Brunswick-Coastal Brunswick-Marion-
Williamsburg-Coastal Horry-Inland Georgetown-Coastal Georgetown-
Central Horry-Northern Horry-
Including the cities of Whiteville, Tabor City, Chadbourn, 
Lake Waccamaw, Burgaw, Surf City, Wilmington, Masonboro, 
Myrtle Grove, Ogden, Carolina Beach, Seagate, 
Boiling Spring Lakes, Leland, Shallotte, Oak Island, Long Beach, 
Southport, Sunset Beach, Marion, Mullins, Kingstree, 
Myrtle Beach, Socastee, North Myrtle Beach, Garden City, 
Little River, Andrews, Georgetown, Murrells Inlet, Conway, Longs,
Bucksport, Loris, Green Sea, and Aynor
701 PM EDT Sat Jul 31 2021

...HEAT ADVISORY HAS EXPIRED...

Heat indices have dropped below the 105 degree threshold and as a
result, the Heat Advisory has been allowed to expire at 7 PM EDT.

$$
dch

The office that day

Everything else NWS Wilmington, NC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 31, 3:07 PM EDTSmall Craft AdvisoryILM35 hr
Jul 31, 6:34 PM EDTSpecial Weather StatementILMPender56 min
Jul 31, 6:55 PM EDTSevere Thunderstorm WarningILMBrunswick, Columbus35 min
Jul 31, 3:59 PM EDTAreal Flood AdvisoryILMGeorgetown37 min
Jul 31, 5:25 PM EDTSpecial Weather StatementILMGeorgetown65 min

Nearby

Heat Advisories in North Carolina, 2021Heat Advisories in South Carolina, 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.