Alert archive / Tennessee / Flash Flood Warnings in 2021

Flash Flood Warning 88, NWS Memphis, TN

December 11, 2021Shelby County, Tennessee; DeSoto County, Mississippi

NWS Memphis, TN issued this flash flood warning at Dec 11, 2021, 2:51 AM CST for Shelby County, Tennessee; DeSoto County, Mississippi. It was in force for 2 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
Dec 11, 2021, 2:51 AM CST (08:51 UTC)
Expired
Dec 11, 2021, 4:51 AM CST
In force
2 hr
Issued by
NWS Memphis, TN
Area
Storm-based polygon
Flood severity
None

Counties DeSoto County, MS, Shelby County, TN

The radar

The Memphis radar (KNQA), 40 km from the middle of the area, began a volume at 08:51 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.

The nearest sounding before it

Little Rock, AR (KLZK), launched 00:00Z, 8.9 hours before the alert went out and 19 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, Little Rock, AR at 00:00Z on 2021-12-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1725 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, Little Rock, AR at 00:00Z on 2021-12-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 398 square meters per square second.1939587897117Sfc1 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
1725 J/kg
Mixed-layer CIN
-13 J/kg
Mixed-layer LCL
759 m above ground
0-6 km bulk shear
78 kt
0-1 km storm-relative helicity
398 m²/s²
0-3 km storm-relative helicity
420 m²/s²
Significant tornado parameter
4.8
Supercell composite
16.2

Open this sounding in Storm Lab

The text

As transmitted.

600 
WGUS54 KMEG 110851
FFWMEG
MSC033-TNC157-111200-
/O.NEW.KMEG.FF.W.0088.211211T0851Z-211211T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Memphis TN
251 AM CST Sat Dec 11 2021

The National Weather Service in Memphis has issued a

* Flash Flood Warning for...
  North Central DeSoto County in northwestern Mississippi...
  South Central Shelby County in western Tennessee...

* Until 600 AM CST.

* At 251 AM CST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 0.5 and 1 inch of rain 
  has fallen. The expected rainfall rate is 1 to 2 inches in 1 hour. 
  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...
  Southaven, Olive Branch, Horn Lake, Memphis, Whitehaven, 
  Lynchburg, Plum Point, Capleville, Jago and Twin Lakes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3506 9003 3506 8980 3498 8978 3493 8994
      3494 9014 3494 9013

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR

$$

TLSJr
1 follow-up statement
457 
WGUS74 KMEG 111051
FFSMEG

Flash Flood Statement
National Weather Service Memphis TN
451 AM CST Sat Dec 11 2021

MSC033-TNC157-111101-
/O.CAN.KMEG.FF.W.0088.000000T0000Z-211211T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
DeSoto MS-Shelby TN-
451 AM CST Sat Dec 11 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NORTH CENTRAL DESOTO AND 
SOUTH CENTRAL SHELBY COUNTIES...

Flooding is no longer expected to pose a threat. Please continue to 
heed remaining road closures.

LAT...LON 3506 9003 3506 8980 3498 8978 3493 8994
      3494 9014 3494 9013

$$

TLSJr

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 10, 7:28 PM CSTTornado Warning EmergencyTornado observedConsiderable damage threatMEGDyer, Lake, Lauderdale47 min
Dec 10, 8:04 PM CSTTornado Warning EmergencyTornado observedCatastrophic damage threatMEGDyer, Lake, Obion41 min
Dec 10, 8:28 PM CSTTornado Warning Tornado observedConsiderable damage threatMEGLake, Obion30 min
Dec 10, 9:24 PM CSTTornado WarningMEGLauderdale51 min
Dec 10, 9:25 PM CSTSevere Thunderstorm Warning Considerable damage threatMEGTipton50 min
Dec 10, 9:52 PM CSTTornado WarningMEGDyer, Lake, Obion38 min
Dec 10, 10:01 PM CSTTornado WarningMEGDyer, Haywood, Lauderdale44 min
Dec 10, 10:27 PM CSTTornado WarningMEGCrockett, Dyer, Gibson, Obion, Weakley48 min
Dec 10, 10:34 PM CSTTornado WarningMEGObion27 min
Dec 10, 10:59 PM CSTTornado Warning Tornado observedConsiderable damage threatMEGHenry, Weakley46 min
Dec 10, 11:20 PM CSTSevere Thunderstorm WarningMEGDyer, Lauderdale15 min
Dec 10, 11:25 PM CSTSevere Thunderstorm WarningMEGShelby9 min
Dec 10, 11:37 PM CSTTornado Warning Tornado observedConsiderable damage threatMEGHenry27 min
Dec 10, 11:41 PM CSTAreal Flood AdvisoryMEGDyer, Gibson, Henry, Lauderdale, Obion, Weakley3 hr
Dec 10, 11:48 PM CSTSevere Thunderstorm WarningMEGFayette, Shelby42 min
Dec 10, 11:52 PM CSTTornado WarningMEGShelby, Tipton34 min
Dec 11, 12:05 AM CSTTornado WarningMEGShelby22 min
Dec 11, 12:26 AM CSTSpecial Weather StatementMEGHenry34 min
Dec 11, 12:30 AM CSTSevere Thunderstorm WarningMEGFayette, Hardeman, Haywood, Shelby, Tipton30 min
Dec 11, 12:35 AM CSTAreal Flood AdvisoryMEGShelby4 hr
Dec 11, 12:36 AM CSTTornado Warning Tornado observedMEGFayette, Hardeman, Haywood24 min
Dec 11, 12:56 AM CSTAreal Flood AdvisoryMEGHenry, Weakley3 hr
Dec 11, 12:57 AM CSTSevere Thunderstorm WarningMEGCarroll, Crockett, Fayette, Gibson, Hardeman, Haywood and 1 more48 min
Dec 11, 12:59 AM CSTSevere Thunderstorm WarningMEGFayette, Hardeman, Shelby31 min
Dec 11, 1:25 AM CSTSevere Thunderstorm WarningMEGBenton, Carroll, Chester, Decatur, Gibson, Hardeman and 2 more65 min
Dec 11, 1:30 AM CSTSpecial Weather StatementMEGFayette, Hardeman30 min
Dec 11, 1:32 AM CSTTornado WarningMEGCarroll, Chester, Henderson, Madison28 min
Dec 11, 1:53 AM CSTTornado WarningMEGBenton, Carroll, Decatur, Henderson25 min
Dec 11, 2:26 AM CSTSpecial Weather StatementMEGDecatur, Hardin, McNairy34 min
Dec 11, 3:03 AM CSTSevere Thunderstorm WarningMEGHardeman, McNairy42 min
Dec 11, 3:19 AM CSTAreal Flood AdvisoryMEGChester, Decatur, Fayette, Hardeman, Hardin, Henderson and 1 more3 hr
Dec 11, 3:21 AM CSTSpecial Weather StatementMEGHardin24 min
Dec 11, 3:30 AM CSTTornado WarningMEGHardin, McNairy21 min
Dec 11, 4:07 AM CSTSpecial Weather StatementMEGHardin23 min
Dec 11, 4:32 AM CSTSpecial Weather StatementMEGHardin28 min
Dec 11, 6:56 AM CSTWind AdvisoryMEGBenton, Carroll, Crockett, Dyer, Gibson, Henry and 4 more5 hr
Dec 10, 10:46 PM CSTSevere Thunderstorm WarningMEGTunica44 min
Dec 11, 12:46 AM CSTSevere Thunderstorm WarningMEGTunica44 min
Dec 11, 12:48 AM CSTSevere Thunderstorm WarningMEGDeSoto, Tunica42 min
Dec 11, 2:12 AM CSTAreal Flood AdvisoryMEGDeSoto, Tunica3 hr
Dec 11, 2:41 AM CSTSevere Thunderstorm WarningMEGBenton, Marshall49 min
Dec 11, 2:44 AM CSTAreal Flood AdvisoryMEGDeSoto2 hr
Dec 11, 2:55 AM CSTSevere Thunderstorm WarningMEGPanola, Tallahatchie, Yalobusha50 min
Dec 11, 3:59 AM CSTSevere Thunderstorm WarningMEGLafayette, Lee, Pontotoc, Union31 min
Dec 11, 4:03 AM CSTFlash Flood WarningMEGCalhoun, Lafayette, Lee, Pontotoc, Prentiss, Tallahatchie and 3 more2 hr
Dec 11, 4:21 AM CSTSevere Thunderstorm WarningMEGItawamba, Lee, Prentiss, Tishomingo39 min
Dec 11, 4:25 AM CSTTornado WarningMEGItawamba, Prentiss, Tishomingo35 min
Dec 11, 4:55 AM CSTAreal Flood AdvisoryMEGAlcorn, Prentiss, Tippah, Tishomingo3 hr
Dec 11, 4:58 AM CSTSevere Thunderstorm WarningMEGItawamba, Lee, Prentiss, Tishomingo47 min
Dec 11, 5:12 AM CSTSevere Thunderstorm WarningMEGItawamba, Lee, Prentiss, Tishomingo33 min
Dec 11, 5:56 AM CSTSpecial Weather StatementMEGMonroe79 min

Nearby

Flash Flood Warnings in Tennessee, 2021Flash Flood Warnings in Mississippi, 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.