Alert archive / Tennessee / Flash Flood Warnings in 2021

Flash Flood Warning 83, NWS Memphis, TN

August 21, 2021Benton County, Henry County, Tennessee

NWS Memphis, TN issued this flash flood warning at Aug 21, 2021, 6:49 AM CDT for Benton County, Henry County, Tennessee. It was in force for 4 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 21, 2021, 6:49 AM CDT (11:49 UTC)
Expired
Aug 21, 2021, 10:45 AM CDT
In force
4 hr
Issued by
NWS Memphis, TN
Area
Storm-based polygon
Flood severity
None

Counties Benton County, TN, Henry County, TN

The radar

The Ft Campbell radar (KHPX), 78 km from the middle of the area, began a volume at 11:49 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

Nashville Metro, TN (KBNA), launched 00:00Z, 11.8 hours before the alert went out and 133 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.

910 
WGUS54 KMEG 211149
FFWMEG
TNC005-079-211445-
/O.NEW.KMEG.FF.W.0083.210821T1149Z-210821T1445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Memphis has issued a

* Flash Flood Warning for...
  Northeastern Benton County in western Tennessee...
  Northeastern Henry County in western Tennessee...

* Until 945 AM CDT.

* At 649 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3 inches of rain 
  have fallen. Additional rainfall amounts of 1 to 2 inches are 
  possible in the warned area. 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...
  Paris Landing State Park, Pine Hill and Big Sandy Unit Tennessee 
  National Wildlife Refuge.

This includes the following streams and drainages...
  Little Crooked Creek, McGehee Branch, Blood River, Trace Creek, 
  Ross Branch, Betsy Branch, Tennessee River and Eagle Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Flooding is occurring or is imminent. It is important to know where 
you are relative to streams, rivers, or creeks which can become 
killers in heavy rains. Campers and hikers should avoid streams or 
creeks.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 3636 8811 3650 8826 3650 8805 3649 8806
      3647 8805 3644 8806 3642 8804 3637 8800
      3634 8797 3629 8795 3625 8795

FLASH FLOOD...RADAR INDICATED

$$
2 follow-up statements
518 
WGUS54 KMEG 211419
FFWMEG
TNC005-079-211545-
/O.EXT.KMEG.FF.W.0083.000000T0000Z-210821T1545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Memphis has extended the

* Flash Flood Warning for...
  Northeastern Benton County in western Tennessee...
  Northeastern Henry County in western Tennessee...

* Until 1045 AM CDT.

* At 919 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3 inches of rain 
  have fallen. Additional rainfall amounts of 1 to 2 inches are 
  possible in the warned area. 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...
  Paris Landing State Park, Pine Hill and Big Sandy Unit Tennessee 
  National Wildlife Refuge.

This includes the following streams and drainages...
  Little Crooked Creek, McGehee Branch, Blood River, Trace Creek, 
  Ross Branch, Betsy Branch, Tennessee River and Eagle Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Flooding is occurring or is imminent. It is important to know where 
you are relative to streams, rivers, or creeks which can become 
killers in heavy rains. Campers and hikers should avoid streams or 
creeks.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 3636 8811 3650 8826 3650 8805 3649 8806
      3647 8805 3644 8806 3642 8804 3637 8800
      3634 8797 3629 8795 3625 8795

FLASH FLOOD...RADAR INDICATED

$$

SWB
927 
WGUS74 KMEG 211551
FFSMEG

Flash Flood Statement
National Weather Service Memphis TN
1051 AM CDT Sat Aug 21 2021

TNC005-079-211601-
/O.EXP.KMEG.FF.W.0083.000000T0000Z-210821T1545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Benton TN-Henry TN-
1051 AM CDT Sat Aug 21 2021

...FLASH FLOOD WARNING HAS EXPIRED FOR NORTHEASTERN BENTON AND 
NORTHEASTERN HENRY COUNTIES...

The heavy rain has ended and the threat for flash flooding is 
diminishing. Please continue to heed remaining road closures.

LAT...LON 3636 8811 3650 8826 3650 8805 3649 8806
      3647 8805 3644 8806 3642 8804 3637 8800
      3634 8797 3629 8795 3625 8795

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 20, 7:17 PM CDTAreal Flood AdvisoryMEGObion3 hr
Aug 21, 6:16 PM CDTAreal Flood AdvisoryMEGHardin3 hr

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.