Alert archive / South Carolina / Special Weather Statements in 2021

Special Weather Statement, NWS Charleston, SC

July 31, 2021Berkeley County, South Carolina

NWS Charleston, SC issued this special weather statement at Jul 31, 2021, 4:00 PM EDT for Berkeley County, South Carolina. It was in force for 30 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 31, 2021, 4:00 PM EDT (20:00 UTC)
Expired
Jul 31, 2021, 4:30 PM EDT
In force
30 min
Issued by
NWS Charleston, SC
Hail
0.00 in
Wind
55

County Berkeley County, SC

The radar

The Wilmington radar (KLTX), 137 km from the middle of the area, began a volume at 20:03 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 12:00Z, 8.0 hours before the alert went out and 56 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 12:00Z on 2021-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2518 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Charleston AFB, SC at 12:00Z on 2021-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 9 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
2518 J/kg
Mixed-layer CIN
-41 J/kg
Mixed-layer LCL
924 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
9 m²/s²
0-3 km storm-relative helicity
67 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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What forecasters said that day

The local office's own words before this special weather statement went out, 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 this special weather statement went out at Jul 31, 1:06 PM EDT, 2 hours 54 minutes earlier.

Area forecast discussion, Jul 31, 1:06 PM EDT, 2 hours 54 minutes before
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      <div class="status" id="status">Temporary Notice</div>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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Hazardous weather outlook, Jul 31, 3:20 AM EDT, 12 hours 40 minutes before
Hazardous Weather Outlook
National Weather Service Charleston SC
320 AM EDT Sat Jul 31 2021

GAZ101-116>119-137>141-SCZ043>045-047>052-010730-
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-
320 AM EDT Sat Jul 31 2021

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

This Hazardous Weather Outlook is for southeast Georgia and
southeast South Carolina.

.DAY ONE...Today and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Heat Advisory.

Severe Thunderstorms: Scattered showers and thunderstorms are
expected to develop over the area this afternoon and evening.
Isolated severe thunderstorms with damaging winds will be possible.
In addition, intense, frequent cloud-to-ground lightning could also
occur. Take shelter if thunderstorms approach.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

Excessive Heat: Heat indices could reach in excess of 110 again
Sunday afternoon for parts of the area. Another Heat Advisory could
be needed.

Heavy Rainfall/Flooding: Unsettled weather will develop across the
area next week as a cold front stalls near the region. Periods of
locally heavy rainfall are likely with flooding possible, especially
in low-lying and poor drainage areas.

.SPOTTER INFORMATION STATEMENT...

Spotter assistance is not anticipated at this time.

GAZ087-088-099-100-114-115-SCZ040-042-010730-
Jenkins-Screven-Candler-Bulloch-Tattnall-Evans-Allendale-Hampton-
320 AM EDT Sat Jul 31 2021

This Hazardous Weather Outlook is for southeast Georgia and
southeast South Carolina.

.DAY ONE...Today and tonight.

Severe Thunderstorms: Scattered showers and thunderstorms are
expected to develop over the area this afternoon and evening.
Isolated severe thunderstorms with damaging winds will be possible.
In addition, intense, frequent cloud-to-ground lightning could also
occur. Take shelter if thunderstorms approach.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

Heavy Rainfall/Flooding: Unsettled weather will develop across the
area next week as a cold front stalls near the region. Periods of
locally heavy rainfall are likely with flooding possible, especially
in low-lying and poor drainage areas.

.SPOTTER INFORMATION STATEMENT...

Spotter assistance is not anticipated at this time.

AMZ330-350-352-354-374-010730-
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-
320 AM EDT Sat Jul 31 2021

This Hazardous Weather Outlook is for Atlantic coastal waters.

.DAY ONE...Today and tonight.

Strong Thunderstorms: Scattered thunderstorms could move into the
coastal waters this afternoon and evening. Wind gusts in excess of 35
kt and intense, frequent cloud-to-water lightning will be possible.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter assistance is not anticipated at this time.

In the hours before

Special weather statement, Jul 31, 11:32 AM EDT, 4 hours 28 minutes before
Special Weather Statement
National Weather Service Charleston SC
1132 AM EDT Sat Jul 31 2021

GAZ087-088-099-100-114-115-SCZ040-042-010000-
Jenkins-Screven-Candler-Bulloch-Tattnall-Evans-Allendale-Hampton-
1132 AM EDT Sat Jul 31 2021

...HEAT INDICES NEAR 110 DEGREES EXPECTED THIS AFTERNOON...

Temperatures in the mid to possibly upper 90s along with moderate
to high humidity will produce heat indices nearing 110 degrees
this afternoon. Heat indices should fall below 100 degrees by 8 PM
this evening.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take extra precautions if you work or spend time outside. When
possible, reschedule strenuous activities to the evening. Know
the signs and symptoms of heat exhaustion and heat stroke. Wear
light weight and loose fitting clothing when possible and drink
plenty of water.

&&
Local storm report, Jul 31, 1:03 PM EDT, 2 hours 57 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHARLESTON SC
103 PM EDT SAT JUL 31 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1155 AM     EXCESSIVE HEAT   MOUNT PLEASANT AIRPORT  32.90N  79.78W
07/31/2021  M117.0 F         CHARLESTON         SC   AWOS

            RECORDED HEAT INDEX AT THE MOUNT PLEASANT AIRPORT
            (KLRO).

&&

EVENT NUMBER CHS2100500

BRM
Special weather statement, Jul 31, 3:25 PM EDT, 35 minutes before
Special Weather Statement
National Weather Service Charleston SC
325 PM EDT Sat Jul 31 2021

SCZ050-312000-
Charleston-
325 PM EDT Sat Jul 31 2021

...STRONG THUNDERSTORMS WILL IMPACT PORTIONS OF CHARLESTON COUNTY...

At 325 PM EDT, National Weather Service doppler radar indicated
strong thunderstorms along a line extending from near Santee Coastal
Reserve to Awendaw, and moving southeast at 10 mph.

HAZARD...strong winds 45 to 55 mph and excessive cloud to ground
         lightning.

SOURCE...Radar Indicated.

IMPACT...Expect minor damage to tree limbs and blowing around of
         light, unsecured objects. All outdoor activities should
         cease. Move indoors immediately.

Some locations in the path of these storms include...
Mount Pleasant, McClellanville, Isle Of Palms, Awendaw, Boone Hall
Plantation, Garris Landing, Mount Pleasant Regional Airport and
Hampton Plantation State Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with these storms and may lead
to flooding of low lying and poor drainage areas. Do not drive your
vehicle through flooded roadways.

Excessive cloud to ground lightning is occurring with these storms.
Lightning can strike 15 miles away from a thunderstorm. Seek safe
shelter inside a building or vehicle.

&&

LAT...LON 3307 7931 3299 7933 3298 7951 3288 7955
      3276 7979 3288 7986 3293 7981 3295 7977
      3298 7977 3313 7962 3316 7956 3314 7952
      3321 7947 3321 7945 3316 7937 3314 7927
      3310 7927
TIME...MOT...LOC 1925Z 306DEG 10KT 3313 7932 3298 7966

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH
Special weather statement, Jul 31, 4:00 PM EDT, 0 minutes before
Special Weather Statement
National Weather Service Charleston SC
400 PM EDT Sat Jul 31 2021

SCZ050-312030-
Charleston-
400 PM EDT Sat Jul 31 2021

...STRONG THUNDERSTORMS WILL IMPACT PORTIONS OF CHARLESTON COUNTY...

At 359 PM EDT, National Weather Service doppler radar indicated
strong thunderstorms along a line extending from near Awendaw to near
Santee Coastal Reserve, and moving east at 10 mph.

HAZARD...strong winds 45 to 55 mph and excessive cloud to ground
         lightning.

SOURCE...Radar Indicated.

IMPACT...Expect minor damage to tree limbs and blowing around of
         light, unsecured objects. All outdoor activities should
         cease. Move indoors immediately.

Some locations in the path of these storms include...
McClellanville, Awendaw, Garris Landing, Hampton Plantation State
Park, Cape Island, Lighthouse Island, Cape Romain and Santee Coastal
Reserve.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with these storms and may lead
to flooding of low lying and poor drainage areas. Do not drive your
vehicle through flooded roadways.

Excessive cloud to ground lightning is occurring with these storms.
Lightning can strike 15 miles away from a thunderstorm. Seek safe
shelter inside a building or vehicle.

&&

LAT...LON 3310 7927 3307 7931 3299 7933 3298 7951
      3288 7955 3297 7977 3315 7954 3314 7952
      3316 7951 3322 7944 3316 7937 3314 7927
TIME...MOT...LOC 1959Z 262DEG 8KT 3301 7963 3314 7932

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 30, 8:01 PM EDTHeat AdvisoryCHSBerkeley, Colleton, Dorchester24 hr
Jul 31, 3:25 PM EDTSpecial Weather StatementCHSCharleston35 min
Jul 31, 3:50 PM EDTAreal Flood AdvisoryCHSBerkeley, Charleston115 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

Special Weather Statements in South Carolina, 2021Every special weather statement 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.