Alert archive / South Carolina / Areal Flood Advisories in 2021

Areal Flood Advisory 59, NWS Columbia, SC

August 16, 2021Calhoun County, Lexington County, Richland County, South Carolina

NWS Columbia, SC issued this areal flood advisory at Aug 16, 2021, 2:43 PM EDT for Calhoun County, Lexington County, Richland County, South Carolina. It was in force for 62 min.

The area

The counties it named.

The facts

Issued
Aug 16, 2021, 2:43 PM EDT (18:43 UTC)
Expired
Aug 16, 2021, 3:45 PM EDT
In force
62 min
Issued by
NWS Columbia, SC
Area
Storm-based polygon

Counties Calhoun County, SC, Lexington County, SC, Richland County, SC

The radar

The Columbia radar (KCAE), 15 km from the middle of the area, began a volume at 18:44 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, 6.7 hours before the alert went out and 141 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 2021-08-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1700 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 2021-08-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 36 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
1700 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
706 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
36 m²/s²
0-3 km storm-relative helicity
60 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.5

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this areal flood advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Columbia, SC wrote its last area forecast discussion before this areal flood advisory went out at Aug 16, 2:12 PM EDT, 31 minutes earlier.

Area forecast discussion, Aug 16, 2:12 PM EDT, 31 minutes before
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Hazardous weather outlook, Aug 16, 4:26 AM EDT, 10 hours 17 minutes before
Hazardous Weather Outlook
National Weather Service Columbia SC
426 AM EDT Mon Aug 16 2021

GAZ040-063>065-077-SCZ016-018-020>022-025>031-035-037-038-041-115-
116-135>137-170830-
Lincoln-McDuffie-Columbia-Richmond-Burke-Chesterfield-McCormick-
Newberry-Fairfield-Kershaw-Edgefield-Saluda-Lexington-Richland-Lee-
Aiken-Sumter-Barnwell-Calhoun-Clarendon-Bamberg-Northern Lancaster-
Southern Lancaster-Northwestern Orangeburg-Central Orangeburg-
Southeastern Orangeburg-
426 AM EDT Mon Aug 16 2021

This Hazardous Weather Outlook is for the Midlands of South Carolina
and the Central Savannah River area of Georgia.

.DAY ONE...Today and tonight.

Periods of heavy rainfall may be possible once again this afternoon
due to slow moving showers and thunderstorms. Depending on how heavy
the rainfall is, there may be some localized flooding of small
streams and low-lying areas.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Periods of heavy rain will be possible Tuesday through Wednesday.
This is in association with remnant surface boundaries and moisture
associated with the remnants of Fred as it slowly moves off to the
west of the area through the middle of the week. Localized flooding
will continue to be possible.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

In the hours before

Special weather statement, Aug 16, 1:20 PM EDT, 1 hour 23 minutes before
Special Weather Statement
National Weather Service Columbia SC
120 PM EDT Mon Aug 16 2021

SCZ028-031-037-038-135>137-161800-
Central Orangeburg SC-Southeastern Orangeburg SC-Calhoun SC-
Clarendon SC-Richland SC-Sumter SC-Northwestern Orangeburg SC-
120 PM EDT Mon Aug 16 2021

...Strong thunderstorms will impact portions of southeastern Calhoun,
southwestern Clarendon, southwestern Sumter, central Orangeburg and
southeastern Richland Counties through 200 PM EDT...

At 119 PM EDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Summerton to near Bowman. Movement was
northwest at 35 mph.

...Boaters on Lake Marion Should Seek Safe Harbor...

HAZARD...Winds in excess of 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Orangeburg, Brookdale, St. Matthews, Summerton, Bowman, Elloree,
Santee State Park, Claflin College, South Carolina State University,
Orangeburg County Airport, Edisto Gardens, Santee, Pinewood, Cameron,
Vance, Cordova, Poplar Creek Landing, Rimini, Fort Motte and
Stumphole Landing.

This includes the following highways...
 Interstate 26 between mile markers 142 and 169.
 Interstate 95 between mile markers 85 and 116.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

If on or near Lake Marion, get out of the water and move indoors or
inside a vehicle. Remember, lightning can strike out to 10 miles
from the parent thunderstorm. If you can hear thunder, you are close
enough to be struck by lightning. Move to safe shelter now! Do not
be caught on the water in a thunderstorm.

Persons in campgrounds should consider seeking sturdy shelter until
these storms pass.

&&

LAT...LON 3333 8049 3333 8051 3330 8057 3346 8101
      3384 8065 3366 8024
TIME...MOT...LOC 1719Z 116DEG 30KT 3364 8030 3331 8059

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

LCV
Special weather statement, Aug 16, 1:30 PM EDT, 1 hour 13 minutes before
Special Weather Statement
National Weather Service Columbia SC
130 PM EDT Mon Aug 16 2021

SCZ020-026>028-161830-
Lexington SC-Newberry SC-Richland SC-Saluda SC-
130 PM EDT Mon Aug 16 2021

...Strong thunderstorms will impact portions of southeastern
Newberry, northwestern Lexington, eastern Saluda and northwestern
Richland Counties through 230 PM EDT...

At 129 PM EDT, Doppler radar was tracking strong thunderstorms along
a line extending from Harbison State Forest to near
Batesburg-Leesville. Movement was northwest at 15 mph.

...Boaters on Lake Murray Should Seek Safe Harbor...

HAZARD...Winds in excess of 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Columbia, Lexington, Irmo, Batesburg-Leesville, St. Andrews, Highway
6 at Lake Murray Dam, Saluda, Columbia International University,
Harbison State Forest, Dreher Island State Park, Ballentine, Chapin,
Gilbert, Summit, Little Mountain, Peak, Cedar Grove Fire Station,
South Shore Marina, Oswald Park and Saluda Co Sheriff's Office.

This includes the following highways...
 Interstate 126 near mile marker 0.
 Interstate 20 in South Carolina near mile marker 49, and between
mile markers 58 and 68.
 Interstate 26 between mile markers 84 and 107.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3429 8134 3427 8134 3424 8131 3423 8128
      3420 8125 3420 8122 3418 8118 3420 8117
      3408 8101 3383 8148 3402 8183
TIME...MOT...LOC 1729Z 126DEG 15KT 3408 8114 3391 8146

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH
Special weather statement, Aug 16, 1:41 PM EDT, 1 hour 2 minutes before
Special Weather Statement
National Weather Service Columbia SC
141 PM EDT Mon Aug 16 2021

GAZ040-063>065-SCZ018-025-030-161815-
Richmond GA-McDuffie GA-Lincoln GA-Columbia GA-Aiken SC-McCormick SC-
Edgefield SC-
141 PM EDT Mon Aug 16 2021

...A strong thunderstorm will impact portions of north central
McDuffie, Columbia, southeastern Lincoln, central Richmond,
southwestern Edgefield, west central Aiken and southeastern McCormick
Counties through 215 PM EDT...

At 140 PM EDT, Doppler radar was tracking a strong thunderstorm over
Augusta, moving northwest at 35 mph.

...Boaters on Lake Strom Thurmond Should Seek Safe Harbor...

HAZARD...Winds in excess of 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
North Augusta, Grovetown, Evans, Fort Gordon, Augusta, Clearwater,
Martinez, Belvedere, Hephzibah, Glendale, South Augusta, Clarks Hill
Recreation Area, Mistletoe State Park, Summerville, Augusta Mall,
Daniel Field, Village Plaza Shopping Center, Augusta National Golf
Club, J. Strom Thurmond Dam and Appling.

This includes the following highways...
 Interstate 20 in Georgia between mile markers 182 and 201.
 Interstate 20 in South Carolina between mile markers 0 and 9.
 Interstate 520 in Georgia between mile markers 1 and 9.
 Interstate 520 in South Carolina between mile markers 17 and 23.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

If on or near Lake Thurmond, get out of the water and move indoors
or inside a vehicle. Remember, lightning can strike out to 10 miles
from the parent thunderstorm. If you can hear thunder, you are close
enough to be struck by lightning. Move to safe shelter now! Do not
be caught on the water in a thunderstorm.

Persons in campgrounds should consider seeking sturdy shelter until
this storm passes.

&&

LAT...LON 3393 8224 3356 8183 3332 8208 3362 8252
TIME...MOT...LOC 1740Z 142DEG 30KT 3348 8197

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

LCV

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 16, 1:20 PM EDTSpecial Weather StatementCAECalhoun, Orangeburg40 min
Aug 16, 1:30 PM EDTSpecial Weather StatementCAESaluda60 min
Aug 16, 5:29 PM EDTAreal Flood AdvisoryCAEAiken, Barnwell, Edgefield, McCormick2 hr
Aug 16, 1:41 PM EDTSpecial Weather StatementCAEColumbia, Richmond34 min

Nearby

Areal Flood Advisories in South Carolina, 2021Every areal flood 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.