Alert archive / Tennessee / Flash Flood Warnings in 2021

Flash Flood Warning 10, NWS Memphis, TN

March 17, 2021Shelby County, Tennessee

NWS Memphis, TN issued this flash flood warning at Mar 17, 2021, 1:54 PM CDT for Shelby County, Tennessee. It was in force for 3 hr. 2 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
Mar 17, 2021, 1:54 PM CDT (18:54 UTC)
Expired
Mar 17, 2021, 5:00 PM CDT
In force
3 hr
Issued by
NWS Memphis, TN
Area
Storm-based polygon
Flood severity
None

County Shelby County, TN

The radar

The Memphis radar (KNQA), 22 km from the middle of the area, began a volume at 18:55 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
Mar 17, 2:00 PM CDTFLASH FLOOD1 N Millington, TNLARGE AREA FLOODED INCLUDING ROADS IN QUITO ESTATES SUBDIVISION IN MILLINGTON.
Mar 17, 3:00 PM CDTFLASH FLOOD2 E Downtown Memphis, TNLARGE AREA FLOODED AT BELVEDERE BLVD AND POPLAR AVE.

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

The nearest sounding before it

Little Rock, AR (KLZK), launched 12:00Z, 6.9 hours before the alert went out and 38 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 12:00Z on 2021-03-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 18 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 12:00Z on 2021-03-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 217 square meters per square second.19395878Sfc1 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
18 J/kg
Mixed-layer CIN
-262 J/kg
Mixed-layer LCL
1466 m above ground
0-6 km bulk shear
65 kt
0-1 km storm-relative helicity
217 m²/s²
0-3 km storm-relative helicity
186 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

As transmitted.

659 
WGUS54 KMEG 171854
FFWMEG
TNC157-172200-
/O.NEW.KMEG.FF.W.0010.210317T1854Z-210317T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Memphis TN
154 PM CDT Wed Mar 17 2021

The National Weather Service in Memphis has issued a

* Flash Flood Warning for...
  Central Shelby County in western Tennessee...

* Until 500 PM CDT.

* At 154 PM 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...Doppler radar.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets and underpasses as well as other
           drainage and low lying areas.

* Some locations that will experience flash flooding include...
  Bartlett, Germantown, Millington, Cordova, T O Fuller State Park, 
  Memphis, Lakeland, Arlington, Frayser, Ellendale, Midtown Memphis, 
  Downtown Memphis, Southwest Memphis, Whitehaven, Raleigh, Elmore 
  Park, Spring Lake, White Station, Lucy and Woodstock.

Additional rainfall amounts of 1 to 2 inches are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

A Flash Flood Warning means that flooding is imminent or occurring. 
If you are in the warned area move to higher ground immediately. 
Residents living along streams and creeks should take immediate 
precautions to protect life and property.

&&

LAT...LON 3515 9010 3525 9005 3538 8993 3536 8972
      3527 8967 3514 8972 3500 9004 3502 9021
      3513 9013 3511 9010 3514 9007 3515 9007

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

$$
2 follow-up statements
960 
WGUS74 KMEG 172004
FFSMEG

Flash Flood Statement
National Weather Service Memphis TN
304 PM CDT Wed Mar 17 2021

TNC157-172200-
/O.CON.KMEG.FF.W.0010.000000T0000Z-210317T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Shelby TN-
304 PM CDT Wed Mar 17 2021

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 500 PM CDT FOR
CENTRAL SHELBY COUNTY...

At 303 PM CDT, The radar estimates 1 to 3 inches of rain has 
occurred over the past 2 hours. Showers and thunderstorms will 
produce an additional inch of rain over the next 2 hours.

HAZARD...Flash flooding caused by heavy rain.

SOURCE...Radar indicated.

IMPACT...Flooding of small creeks and streams, urban areas, 
         highways, streets and underpasses as well as other drainage 
         and low lying areas.

Some locations that will experience flooding include...
Bartlett, Germantown, Millington, T O Fuller State Park, Cordova,
Memphis, Lakeland, Arlington, Southwest Memphis, Ellendale, Downtown
Memphis, Whitehaven, Frayser, Midtown Memphis, Lenow, Woodstock,
Rosemark, Presidents Island, Sloanville and Elmore Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 3515 9010 3525 9005 3538 8993 3536 8972
      3527 8967 3514 8972 3500 9004 3502 9021
      3513 9013 3511 9010 3514 9007 3515 9007

FLASH FLOOD...RADAR INDICATED

$$

TLSJr
399 
WGUS74 KMEG 172154
FFSMEG

Flash Flood Statement
National Weather Service Memphis TN
454 PM CDT Wed Mar 17 2021

TNC157-172204-
/O.EXP.KMEG.FF.W.0010.000000T0000Z-210317T2200Z/
/00000.U.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Shelby TN-
454 PM CDT Wed Mar 17 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 5 PM CDT THIS AFTERNOON FOR 
CENTRAL SHELBY COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures. Additional 
rain later this evening may warrant another flash flood warning for 
the area.

LAT...LON 3515 9010 3525 9005 3538 8993 3536 8972
      3527 8967 3514 8972 3500 9004 3502 9021
      3513 9013 3511 9010 3514 9007 3515 9007

$$

TLSJr

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 17, 6:49 AM CDTSevere Thunderstorm WarningMEGFayette14 min
Mar 17, 9:04 AM CDTFlash Flood WarningMEGFayette, Hardeman, McNairy3 hr
Mar 17, 11:38 AM CDTFlash Flood WarningMEGShelby, Tipton3 hr
Mar 17, 12:24 PM CDTSpecial Weather StatementMEGShelby36 min
Mar 17, 12:31 PM CDTSpecial Weather StatementMEGTipton29 min
Mar 17, 1:18 PM CDTSevere Thunderstorm WarningMEGChester, Fayette, Hardeman, Haywood, Madison, Tipton42 min
Mar 17, 1:58 PM CDTSevere Thunderstorm WarningMEGChester, Decatur, Hardeman, Henderson, Madison47 min
Mar 17, 5:26 PM CDTRiver Flood WarningMEGCrockett, Dyer, Lauderdale15 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.