Alert archive / Tennessee / Flash Flood Warnings in 2017

Flash Flood Warning 21, NWS Memphis, TN

May 11, 2017Crockett County, Dyer County, Lauderdale County, Tennessee

NWS Memphis, TN issued this flash flood warning at May 11, 2017, 8:25 PM CDT for Crockett County, Dyer County, Lauderdale County, Tennessee. It was in force for 3 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
May 11, 2017, 8:25 PM CDT (01:25 UTC)
Expired
May 11, 2017, 11:30 PM CDT
In force
3 hr
Issued by
NWS Memphis, TN
Area
Storm-based polygon
Flood severity
None

Counties Crockett County, TN, Dyer County, TN, Lauderdale County, TN

The radar

The Memphis radar (KNQA), 72 km from the middle of the area, began a volume at 01:28 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 (KBYH), launched 00:00Z, 1.4 hours before the alert went out and 125 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 2017-05-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 976 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 2017-05-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 65 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
976 J/kg
Mixed-layer CIN
-21 J/kg
Mixed-layer LCL
1041 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
65 m²/s²
0-3 km storm-relative helicity
6 m²/s²
Significant tornado parameter
0.2
Supercell composite
2.6

Open this sounding in Storm Lab

The text

As transmitted.

476 
WGUS54 KMEG 120125
FFWMEG
TNC033-045-097-120430-
/O.NEW.KMEG.FF.W.0021.170512T0125Z-170512T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Memphis TN
825 PM CDT THU MAY 11 2017

The National Weather Service in Memphis has issued a

* Flash Flood Warning for...
  Northwestern Crockett County in western Tennessee...
  Southeastern Dyer County in western Tennessee...
  Northeastern Lauderdale County in western Tennessee...

* Until 1130 PM CDT

* At 825 PM CDT...Doppler Radar estimates 1 to 3 inches of rain has
  occurred over the past hour. Showers and thunderstorms will produce
  an additional 1 to 3 inches of rain over the next 2 hours.

* Some locations that will experience flooding include...
  Halls, Chestnut Bluff, Unionville, Friendship, Gates, South Fork,
  Poplar Grove, Hawkinsville, Porter Gap, Edith, Fowlkes, Dryhill,
  Parker, Curve, Dog Hill, Bonicord, Double Bridges, Frog Jump,
  Nankipoo and Maury Junction.

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.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 3585 8918 3581 8935 3582 8936 3582 8940
      3580 8942 3579 8945 3589 8965 3592 8965
      3602 8925

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 11, 7:13 PM CDTSevere Thunderstorm WarningMEGLauderdale32 min
May 11, 8:01 PM CDTSevere Thunderstorm WarningMEGCrockett, Dyer, Lauderdale29 min

Nearby

Flash Flood Warnings in Tennessee, 2017Every flash flood warning in 2017

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.