Alert archive / Tennessee / Flash Flood Warnings in 2011

Flash Flood Warning 16, NWS Nashville, TN

April 24, 2011Sumner County, Tennessee

NWS Nashville, TN issued this flash flood warning at Apr 24, 2011, 12:47 PM CDT for Sumner County, Tennessee. It was in force for 118 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Apr 24, 2011, 12:47 PM CDT (17:47 UTC)
Expired: Apr 24, 2011, 2:45 PM CDT
In force: 118 min
Issued by: NWS Nashville, TN
Area: Storm-based polygon
Flood severity: None

County Sumner County, TN

The radar

The Nashville radar (KOHX), 24 km from the middle of the area, began a volume at 17:48 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, 5.8 hours before the alert went out and 37 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1536 J/kg
Mixed-layer CIN: -11 J/kg
Mixed-layer LCL: 557 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 163 m²/s²
0-3 km storm-relative helicity: 219 m²/s²
Significant tornado parameter: 1.2
Supercell composite: 5.8

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

182 
WGUS54 KOHX 241747
FFWOHX
TNC165-241945-
/O.NEW.KOHX.FF.W.0016.110424T1747Z-110424T1945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NASHVILLE TN
1247 PM CDT SUN APR 24 2011

THE NATIONAL WEATHER SERVICE IN NASHVILLE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SUMNER COUNTY IN MIDDLE TENNESSEE...
  THIS INCLUDES THE CITY OF GALLATIN...

* UNTIL 245 PM CDT

* AT 1243 PM CDT...THE PUBLIC REPORTED FLASH FLOODING FROM A
  THUNDERSTORM OVER WESTERN SUMNER COUNTY...IN THE WHITE HOUSE AREA.
  LOOK FOR HEAVY RAINS WITH THE THUNDERSTORM COMPLEX AS IT MOVES THROUGH
  THE SUMNER COUNTY AREA CAUSING FLOODING OF ROADWAYS...CREEKS AND STREAMS.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO PORTLAND

LAT...LON 3663 8622 3635 8636 3634 8638 3631 8638
      3632 8642 3633 8642 3633 8645 3637 8672
      3663 8655

$$

BOYD

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 24, 12:34 AM CDT	Severe Thunderstorm Warning	OHX	Cheatham, Davidson, Robertson	26 min
Apr 24, 12:13 PM CDT	Severe Thunderstorm Warning	OHX	Davidson, Robertson, Sumner	47 min
Apr 24, 12:37 PM CDT	Tornado Warning	OHX	Davidson, Robertson, Sumner	38 min
Apr 24, 1:06 PM CDT	Tornado Warning	OHX	Sumner, Trousdale, Wilson	24 min
Apr 24, 1:22 PM CDT	Severe Thunderstorm Warning	OHX	Macon, Sumner, Trousdale	39 min
Apr 24, 1:36 PM CDT	Severe Thunderstorm Warning	OHX	Clay, Macon, Sumner, Trousdale	54 min
Apr 24, 2:24 PM CDT	Severe Thunderstorm Warning	OHX	Clay, Jackson, Macon, Pickett	66 min

Nearby

Flash Flood Warnings in Tennessee, 2011 Every flash flood warning in 2011

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.