Alert archive / Tennessee / Flash Flood Warnings in 2021

Flash Flood Warning 78, NWS Memphis, TN

August 15, 2021Hardin County, Tennessee

NWS Memphis, TN issued this flash flood warning at Aug 15, 2021, 1:24 PM CDT for Hardin 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 15, 2021, 1:24 PM CDT (18:24 UTC)
Expired
Aug 15, 2021, 5:30 PM CDT
In force
4 hr
Issued by
NWS Memphis, TN
Area
Storm-based polygon
Flood severity
None

County Hardin County, TN

The radar

The Columbus AFB radar (KGWX), 136 km from the middle of the area, began a volume at 18:25 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 12:00Z, 6.4 hours before the alert went out and 173 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 12:00Z on 2021-08-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 152 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 12:00Z on 2021-08-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 23 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
152 J/kg
Mixed-layer CIN
-98 J/kg
Mixed-layer LCL
697 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
36 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

884 
WGUS54 KMEG 151824
FFWMEG
TNC071-152130-
/O.NEW.KMEG.FF.W.0078.210815T1824Z-210815T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Memphis TN
124 PM CDT Sun Aug 15 2021

The National Weather Service in Memphis has issued a

* Flash Flood Warning for...
  Southeastern Hardin County in western Tennessee...

* Until 430 PM CDT.

* At 124 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 4 inches of rain 
  have fallen. Additional rainfall amounts of 2 to 4 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...
  Walnut Grove, Lowryville and Pollards Mill.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3501 8798 3501 8816 3512 8814 3514 8806
      3521 8798 3517 8798 3513 8798 3505 8798

FLASH FLOOD...RADAR INDICATED

$$
2 follow-up statements
827 
WGUS54 KMEG 152046
FFWMEG
TNC071-152230-
/O.EXT.KMEG.FF.W.0078.000000T0000Z-210815T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Memphis TN
346 PM CDT Sun Aug 15 2021

The National Weather Service in Memphis has extended the

* Flash Flood Warning for...
  Southeastern Hardin County in western Tennessee...

* Until 530 PM CDT.

* At 346 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 3 and 5 inches of rain 
  have fallen. The expected rainfall rate is 1 to 3 inches in 2 
  hours. Additional rainfall amounts of 2 to 4 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...
  Walnut Grove, Lowryville and Pollards Mill.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3501 8798 3501 8816 3512 8814 3514 8806
      3521 8798 3517 8798 3513 8798 3505 8798

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-3 INCHES IN 2 HOURS

$$
781 
WGUS74 KMEG 152230
FFSMEG

Flash Flood Statement
National Weather Service Memphis TN
530 PM CDT Sun Aug 15 2021

TNC071-152240-
/O.EXP.KMEG.FF.W.0078.000000T0000Z-210815T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hardin TN-
530 PM CDT Sun Aug 15 2021

...FLASH FLOOD WARNING HAS EXPIRED FOR SOUTHEASTERN HARDIN COUNTY...

Flood waters have receded. The heavy rain has ended. Flooding is no 
longer expected to pose a threat. Please continue to heed remaining 
road closures.

LAT...LON 3501 8798 3501 8816 3512 8814 3514 8806
      3521 8798 3517 8798 3513 8798 3505 8798

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 15, 12:41 PM CDTAreal Flood AdvisoryMEGHardin43 min
Aug 15, 1:26 PM CDTAreal Flood AdvisoryMEGHardin4 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.