Alert archive / South Carolina / Tornado Warnings in 2020

Tornado Warning 23, NWS Columbia, SC

September 17, 2020Lee County, Sumter County, South Carolina

NWS Columbia, SC issued this tornado warning at Sep 17, 2020, 11:27 AM EDT for Lee County, Sumter County, South Carolina. It was in force for 48 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Sep 17, 2020, 11:27 AM EDT (15:27 UTC)
Expired: Sep 17, 2020, 12:15 PM EDT
In force: 48 min
Issued by: NWS Columbia, SC
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.0 in

Counties Lee County, SC, Sumter County, SC

The radar

The Columbia radar (KCAE), 82 km from the middle of the area, began a volume at 15:30 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.

What was reported inside it

Time	Report	Where	Remark
Sep 17, 11:43 AM EDT	TORNADO	4 Ese South Sumter, SC	A NATIONAL WEATHER SERVICE STORM SURVEY TEAM CONFIRMED AN EF-0 TORNADO, WITH PEAK WINDS OF 80 MPH, EAST OF SUMTER IN SUMTER COUNTY, SC. THE TORNADO BEGAN NEAR MIMS RD AND LONDON RD, MOVED NORTHEAST PARALLEL TO CAMP BRANCH RD, TURNED NORTHWARD AS IT CROSSED HIG

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Sep 17, 10:20 AM EDT	Tornado Watch	SPC	8 hr

The nearest sounding before it

Charleston AFB, SC (KCHS), launched 12:00Z, 3.5 hours before the alert went out and 114 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1154 J/kg
Mixed-layer CIN: -13 J/kg
Mixed-layer LCL: 652 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 188 m²/s²
0-3 km storm-relative helicity: 261 m²/s²
Significant tornado parameter: 1.0
Supercell composite: 5.7

Open this sounding in Storm Lab

The text

As transmitted.

836 
WFUS52 KCAE 171527
TORCAE
SCC061-085-171615-
/O.NEW.KCAE.TO.W.0023.200917T1527Z-200917T1615Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Columbia SC
1127 AM EDT Thu Sep 17 2020

The National Weather Service in Columbia has issued a

* Tornado Warning for...
  Southern Lee County in central South Carolina...
  Central Sumter County in central South Carolina...

* Until 1215 PM EDT.
    
* At 1127 AM EDT, a severe thunderstorm capable of producing a
  tornado was located near South Sumter, moving north at 25 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This dangerous storm will be near...
  Sumter around 1135 AM EDT.
  South Sumter and Millwood around 1140 AM EDT.
  Mulberry around 1145 AM EDT.
  Sumter County Airport around 1150 AM EDT.

Other locations impacted by this tornadic thunderstorm include
Oswego, East Sumter, St. Charles, Mayesville, Brogdon, Lakewood,
Lynchburg and Dalzell.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! If you are outdoors, in a mobile home, or in a
vehicle, move to an interior room or closet on the lowest floor of a
sturdy building immediately.

&&

LAT...LON 3385 8016 3379 8027 3379 8035 3409 8042
      3405 8000
TIME...MOT...LOC 1527Z 192DEG 22KT 3382 8028 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$

JAQ

2 follow-up statements

830 
WWUS52 KCAE 171548
SVSCAE

Severe Weather Statement
National Weather Service Columbia SC
1148 AM EDT Thu Sep 17 2020

SCC061-085-171615-
/O.CON.KCAE.TO.W.0023.000000T0000Z-200917T1615Z/
Lee SC-Sumter SC-
1148 AM EDT Thu Sep 17 2020

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1215 PM EDT FOR SOUTHERN
LEE AND CENTRAL SUMTER COUNTIES...
    
At 1148 AM EDT, a severe thunderstorm capable of producing a tornado
was located near South Sumter, moving north at 15 mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  Mulberry around 1200 PM EDT.
  Sumter County Airport around 1215 PM EDT.

Other locations impacted by this tornadic thunderstorm include
Oswego, Mayesville, East Sumter, St. Charles, Lynchburg and Lakewood.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! If you are outdoors, in a mobile home, or in a
vehicle, move to an interior room or closet on the lowest floor of a
sturdy building immediately.

&&

LAT...LON 3385 8016 3383 8027 3387 8035 3409 8042
      3405 8000
TIME...MOT...LOC 1548Z 193DEG 11KT 3389 8026 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$

JAQ

730 
WWUS52 KCAE 171615
SVSCAE

Severe Weather Statement
National Weather Service Columbia SC
1215 PM EDT Thu Sep 17 2020

SCC061-085-171625-
/O.EXP.KCAE.TO.W.0023.000000T0000Z-200917T1615Z/
Lee SC-Sumter SC-
1215 PM EDT Thu Sep 17 2020

...THE TORNADO WARNING FOR SOUTHERN LEE AND CENTRAL SUMTER COUNTIES
HAS EXPIRED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning has been allowed to expire.

A Tornado Watch remains in effect until 600 PM EDT for central South
Carolina.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Columbia.

LAT...LON 3385 8016 3383 8027 3387 8035 3409 8042
      3405 8000
TIME...MOT...LOC 1615Z 192DEG 22KT 3405 8022 

$$

JAQ

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 16, 11:22 PM EDT	River Flood Advisory	CAE	Lexington, Richland	46 hr
Sep 17, 7:56 AM EDT	Tornado Warning	CAE	Richland, Sumter	34 min
Sep 17, 8:09 AM EDT	Tornado Warning Tornado observed	CAE	Calhoun, Richland, Sumter	21 min
Sep 17, 8:30 AM EDT	Flash Flood Warning	CAE	Aiken, Edgefield, McCormick	3 hr
Sep 17, 9:22 AM EDT	Flash Flood Warning	CAE	Aiken, Barnwell, Edgefield, McCormick, Newberry, Saluda	3 hr
Sep 17, 9:33 AM EDT	Tornado Warning	CAE	Calhoun, Orangeburg	27 min
Sep 17, 9:46 AM EDT	River Flood Warning	CAE	Calhoun, Lexington, Richland	35 hr
Sep 17, 9:46 AM EDT	River Flood Warning	CAE	Calhoun, Richland	3 days
Sep 17, 9:46 AM EDT	River Flood Warning	CAE	Edgefield, McCormick	12 hr
Sep 17, 10:00 AM EDT	Tornado Warning	CAE	Calhoun, Clarendon, Orangeburg	45 min
Sep 17, 10:28 AM EDT	Flash Flood Warning	CAE	Bamberg, Calhoun, Clarendon, Orangeburg, Richland, Sumter	3 hr
Sep 17, 10:38 AM EDT	Flash Flood Warning	CAE	Aiken, Bamberg, Barnwell, Calhoun, Fairfield, Kershaw and 6 more	3 hr
Sep 17, 10:44 AM EDT	Tornado Warning	CAE	Clarendon, Sumter	46 min
Sep 17, 11:01 AM EDT	Tornado Warning	CAE	Clarendon, Sumter	29 min
Sep 17, 11:44 AM EDT	Tornado Warning	CAE	Calhoun, Clarendon, Orangeburg, Sumter	46 min
Sep 17, 12:06 PM EDT	Flash Flood Warning	CAE	Clarendon, Kershaw, Lee, Richland, Sumter	3 hr
Sep 17, 12:39 PM EDT	Tornado Warning	CAE	Clarendon, Sumter	33 min
Sep 17, 12:56 PM EDT	Tornado Warning	CAE	Calhoun, Clarendon, Orangeburg	36 min
Sep 17, 1:11 PM EDT	Tornado Warning	CAE	Sumter	49 min
Sep 17, 1:34 PM EDT	Flash Flood Warning	CAE	Calhoun, Clarendon, Orangeburg, Richland, Sumter	3 hr
Sep 17, 2:37 PM EDT	Severe Thunderstorm Warning	CAE	Lee, Sumter	23 min
Sep 17, 2:52 PM EDT	Severe Thunderstorm Warning	CAE	Clarendon	40 min
Sep 17, 3:02 PM EDT	Tornado Warning	CAE	Clarendon, Sumter	28 min
Sep 17, 3:19 PM EDT	Flash Flood Warning	CAE	Clarendon, Lee, Sumter	3 hr
Sep 17, 5:45 PM EDT	Areal Flood Advisory	CAE	Clarendon, Orangeburg, Sumter	60 min
Sep 17, 6:08 PM EDT	Special Weather Statement	CAE	Clarendon	22 min

Nearby

Tornado Warnings in South Carolina, 2020 Every tornado warning in 2020 Tornadoes in 2020

Sources

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