Alert archive / Tennessee / Flash Flood Warnings in 2021

Flash Flood Warning 49, NWS Nashville, TN

August 21, 20214 counties in Tennessee

NWS Nashville, TN issued this flash flood warning at Aug 21, 2021, 4:49 AM CDT for 4 counties in Tennessee. It was in force for 3 hr. 6 reports 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
Aug 21, 2021, 4:49 AM CDT (09:49 UTC)
Expired
Aug 21, 2021, 8:00 AM CDT
In force
3 hr
Issued by
NWS Nashville, TN
Area
Storm-based polygon
Flood severity
None

Counties Dickson County, TN, Hickman County, TN, Houston County, TN, Humphreys County, TN

The radar

The Nashville radar (KOHX), 73 km from the middle of the area, began a volume at 09:51 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

TimeReportWhereRemark
Aug 21, 5:12 AM CDTFLASH FLOOD3 Sw Dickson, TNMULTIPLE ROADS CLOSED DUE TO HIGH WATER THROUGHOUT THE SOUTHERN PART OF THE COUNTY AND IN DICKSON
Aug 21, 7:00 AM CDTFLASH FLOODDickson, TNHIGHWAY 46 NEAR COLLEGE STREET CLOSED DUE TO FLOODING.
Aug 21, 7:50 AM CDTFLASH FLOOD3 E Lyles, TNTATUM ROAD BETWEEN HIGHWAY 100 AND HIGHWAY 7 IMPASSABLE DUE TO FLOODING.
Aug 21, 8:00 AM CDTFLASH FLOODDickson, TNCOUNTY-WIDE, TOO MANY WATER RESCUES TO COUNT. NUMEROUS ROADS DAMAGED OR CLOSED ACROSS DICKSON COUNTY.
Aug 21, 8:03 AM CDTFLASH FLOOD2 Ene Dickson, TNHOMES FLOODING AROUND GREYSTONE GOLF CLUB IN DICKSON.
Aug 21, 8:09 AM CDTFLASH FLOOD1 Se Dickson, TNSEVERAL HOMES FLOODED ON ROYAL OAK DRIVE IN DICKSON.

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

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 00:00Z, 9.8 hours before the alert went out and 67 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, Nashville Metro, TN at 00:00Z on 2021-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 689 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, Nashville Metro, TN at 00:00Z on 2021-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -18 square meters per square second.193958Sfc1 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
689 J/kg
Mixed-layer CIN
-31 J/kg
Mixed-layer LCL
1089 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
-18 m²/s²
0-3 km storm-relative helicity
-2 m²/s²
Significant tornado parameter
-0.1
Supercell composite
-1.1

Open this sounding in Storm Lab

The text

As transmitted.

543 
WGUS54 KOHX 210949
FFWOHX
TNC043-081-083-085-211300-
/O.NEW.KOHX.FF.W.0049.210821T0949Z-210821T1300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Nashville TN
449 AM CDT Sat Aug 21 2021

The National Weather Service in Nashville has issued a

* Flash Flood Warning for...
  Dickson County in middle Tennessee...
  Northeastern Hickman County in middle Tennessee...
  Southeastern Houston County in middle Tennessee...
  Northeastern Humphreys County in middle Tennessee...

* Until 800 AM CDT.

* At 449 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3 inches of rain 
  have fallen. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Dickson, White Bluff, Burns, Charlotte, Vanleer, Slayden, Bon Aqua 
  and Lyles.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 3620 8771 3632 8745 3624 8721 3602 8719
      3597 8720 3597 8721 3596 8721 3584 8724

FLASH FLOOD...RADAR INDICATED

$$

10
1 follow-up statement
543 
WGUS74 KOHX 211109
FFSOHX

Flash Flood Statement
National Weather Service Nashville TN
609 AM CDT Sat Aug 21 2021

TNC043-081-083-085-211300-
/O.CON.KOHX.FF.W.0049.000000T0000Z-210821T1300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Dickson TN-Hickman TN-Houston TN-Humphreys TN-
609 AM CDT Sat Aug 21 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 8 AM CDT THIS MORNING 
FOR DICKSON, NORTHEASTERN HICKMAN, SOUTHEASTERN HOUSTON AND 
NORTHEASTERN HUMPHREYS COUNTIES...

At 609 AM CDT, local law enforcement reported thunderstorms 
producing heavy rain across the warned area. Between 3.5 and 6 
inches of rain have fallen. Flash flooding is already occurring.

HAZARD...Life threatening flash flooding. Thunderstorms producing
         flash flooding.

SOURCE...Law enforcement reported.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Dickson, White Bluff, Burns, Charlotte, Vanleer, Slayden, Bon Aqua 
  and Lyles.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3620 8771 3632 8745 3624 8721 3602 8719
      3597 8720 3597 8721 3596 8721 3584 8724

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

10

The office that day

Everything else NWS Nashville, TN issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 21, 2:48 AM CDTAreal Flood AdvisoryOHXDickson, Hickman, Humphreys, Lewis2 hr
Aug 21, 3:29 AM CDTFlash Flood WarningOHXDickson, Hickman, Humphreys5 hr
Aug 21, 4:10 AM CDTAreal Flood AdvisoryOHXGiles, Lawrence, Lewis, Maury3 hr
Aug 21, 4:29 AM CDTAreal Flood AdvisoryOHXMontgomery, Stewart3 hr
Aug 21, 6:24 AM CDTFlash Flood WarningOHXHouston, Humphreys, Stewart5 hr
Aug 21, 7:47 AM CDTFlash Flood Warning EmergencyCatastrophic damage threatOHXDickson, Hickman, Houston, Humphreys9 hr
Aug 21, 8:39 AM CDTRiver Flood WarningOHXHickman13 hr
Aug 21, 9:41 AM CDTAreal Flood AdvisoryOHXHickman, Lewis, Maury3 hr
Aug 21, 10:12 AM CDTFlash Flood WarningOHXHickman, Humphreys, Lewis, Maury, Perry3 hr
Aug 21, 10:17 AM CDTRiver Flood AdvisoryOHXHickman52 hr
Aug 21, 11:39 AM CDTAreal Flood AdvisoryOHXGiles, Lawrence, Marshall3 hr
Aug 21, 12:33 PM CDTRiver Flood WarningOHXHumphreys44 hr
Aug 21, 4:40 PM CDTAreal Flood AdvisoryOHXHouston, Stewart3 hr
Aug 21, 4:55 PM CDTFlash Flood WarningOHXDickson, Hickman, Houston, Humphreys6 hr
Aug 21, 5:07 PM CDTFlash Flood WarningOHXDickson, Houston, Montgomery, Stewart4 hr
Aug 21, 5:10 PM CDTSpecial Weather StatementOHXHouston, Stewart50 min
Aug 21, 5:30 PM CDTSpecial Weather StatementOHXDickson, Houston45 min
Aug 21, 5:43 PM CDTSpecial Weather StatementOHXLawrence47 min
Aug 21, 5:57 PM CDTTornado WarningOHXDickson16 min
Aug 21, 5:58 PM CDTFlash Flood WarningOHXCheatham, Dickson, Houston, Montgomery3 hr
Aug 21, 6:17 PM CDTSpecial Weather StatementOHXDickson43 min
Aug 21, 6:29 PM CDTSpecial Weather StatementOHXHickman31 min
Aug 21, 6:53 PM CDTSpecial Weather StatementOHXWilliamson37 min

Nearby

Flash Flood Warnings in Tennessee, 2021Every flash flood warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.