Alert archive / Tennessee / Flash Flood Warnings in 2012

Flash Flood Warning 21, NWS Nashville, TN

September 17, 20128 counties in Tennessee

NWS Nashville, TN issued this flash flood warning at Sep 17, 2012, 7:12 PM CDT for 8 counties in Tennessee. It was in force for 6 hr. 3 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: Sep 17, 2012, 7:12 PM CDT (00:12 UTC)
Expired: Sep 18, 2012, 1:00 AM CDT
In force: 6 hr
Issued by: NWS Nashville, TN
Area: Storm-based polygon
Flood severity: None

Counties Clay County, TN, DeKalb County, TN, Fentress County, TN, Jackson County, TN, Overton County, TN, Pickett County, TN, Putnam County, TN, White County, TN

The radar

The Nashville radar (KOHX), 117 km from the middle of the area, began a volume at 00:15 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

Time	Report	Where	Remark
Sep 17, 7:17 PM CDT	FLASH FLOOD	Cookeville, TN	MUTIPLE VEHICLES STRANDED IN THE COOKEVILLE AREA. WITH WATER RESCUES ONGOING. MEASURED 3.88 INCHES OF RAINFALL AT PUTNAM COUNTY EOC.
Sep 17, 9:02 PM CDT	FLASH FLOOD	Sparta, TN	SEVERAL ROADS FLOODED IN WHITE COUNTY INCLUDING RIVER RD...HICKORY VALLEY RD...BOCKMAN WAY...NORTH SPRING RD...AND OLD SMITHVILLE HWY.
Sep 17, 9:02 PM CDT	HEAVY RAIN 5.41	Sparta, TN

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

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 00:00Z, 0.2 hours before the alert went out and 123 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: 168 J/kg
Mixed-layer CIN: 0 J/kg
Mixed-layer LCL: 471 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 45 m²/s²
0-3 km storm-relative helicity: 57 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

879 
WGUS54 KOHX 180012
FFWOHX
TNC027-041-049-087-133-137-141-185-180600-
/O.NEW.KOHX.FF.W.0021.120918T0012Z-120918T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NASHVILLE TN
712 PM CDT MON SEP 17 2012

THE NATIONAL WEATHER SERVICE IN NASHVILLE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EASTERN CLAY COUNTY IN MIDDLE TENNESSEE...
  EASTERN DE KALB COUNTY IN MIDDLE TENNESSEE...
  NORTHERN WHITE COUNTY IN MIDDLE TENNESSEE...
  NORTHWESTERN FENTRESS COUNTY IN MIDDLE TENNESSEE...
  OVERTON COUNTY IN MIDDLE TENNESSEE...
  PICKETT COUNTY IN MIDDLE TENNESSEE...
  PUTNAM COUNTY IN MIDDLE TENNESSEE...
  SOUTHEASTERN JACKSON COUNTY IN MIDDLE TENNESSEE...

* UNTIL 100 AM CDT

* AT 706 PM CDT...LOCAL LAW ENFORCEMENT OFFICIALS AND WEATHER    
  SPOTTERS REPORTED AN AREA OF HEAVY RAINFALL FROM              
  SMITHVILLE...TO COOKEVILLE AND LIVINGSTON. RAINFALL AMOUNTS FROM
  2 TO 3 INCHES HAVE BEEN COMMON...AND SOME LOCATIONS IN THE 
  COOKEVILLE AREA HAVE HAD MORE THAN 5 INCHES OF RAIN TODAY.
  STREET FLOODING WAS REPORTED...WITH SEVERAL FEET OF WATER OVER 
  SOME ROADS.

* ADDITIONAL MODERATE TO HEAVY RAINFALL THIS EVENING WILL CAUSE
  FLASH FLOODING TO OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE 
  FLOODING INCLUDE...BYRDSTOWN...COOKEVILLE...LIVINGSTON... 
  SMITHVILLE...SPARTA...ALGOOD...BAXTER AND MONTEREY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL 
CREEKS AND STREAMS...ROADS...AS WELL AS FARMLAND ALONG THE BANKS OF 
CREEKS AND STREAMS. DO NOT DRIVE INTO AREAS WHERE WATER COVERS THE 
ROAD. 

&&

LAT...LON 3661 8492 3588 8540 3589 8591 3663 8537
      3663 8507

$$

13

1 follow-up statement

811 
WGUS74 KOHX 180144
FFSOHX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
844 PM CDT MON SEP 17 2012

TNC027-041-049-087-133-137-141-185-180600-
/O.CON.KOHX.FF.W.0021.000000T0000Z-120918T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
OVERTON TN-PICKETT TN-PUTNAM TN-WHITE TN-CLAY TN-DE KALB TN-
FENTRESS TN-JACKSON TN-
844 PM CDT MON SEP 17 2012

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR SOUTHEASTERN JACKSON...
NORTHWESTERN FENTRESS...EASTERN DE KALB...EASTERN CLAY...NORTHERN
WHITE...PUTNAM...PICKETT AND OVERTON COUNTIES UNTIL 100 AM CDT...

AT 838 PM CDT...WEATHER SPOTTERS REPORTED HEAVY RAINFALL ACROSS THE 
WARNED AREA. RAINFALL TOTALS OVER 3 INCHES WERE COMMON...AND A FEW 
LOCATIONS AROUND COOKEVILLE REPORTED WELL OVER 5 INCHES OF RAIN.

MODERATE TO HEAVY RAIN CONTINUED OVER THE AREA. THE ADDITIONAL RAIN 
WILL CONTINUE TO CAUSE PROBLEMS WITH FLOODED ROADS AND HIGH WATER 
LEVELS ON SMALL STREAMS. FORTUNATELY...IT APPEARS THE RAIN WILL BE 
DECREASING IN INTENSITY OVER THE NEXT COUPLE OF HOURS. SOME 
LOCATIONS THAT WILL EXPERIENCE FLASH FLOODING 
INCLUDE...BYRDSTOWN...COOKEVILLE...LIVINGSTON...SMITHVILLE...SPARTA..
.ALGOOD...BAXTER AND MONTEREY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLOODING OF SMALL CREEKS 
AND STREAMS...ROADS...NORMALLY DRY WASHES... AS WELL AS FARMLAND 
ALONG THE BANKS OF CREEKS AND STREAMS.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLOODING IS OBSERVED...ACT QUICKLY. DO NOT
ENTER THE WATER. TURN AROUND AND MOVE UP TO HIGHER GROUND.

&&

LAT...LON 3661 8492 3588 8540 3589 8591 3663 8537
      3663 8507

$$

13

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 17, 7:58 PM CDT	River Flood Advisory	OHX	Bedford	11 hr
Sep 18, 2:51 AM CDT	Areal Flood Warning	OHX	Bedford, Cannon, Coffee, Grundy, Van Buren, Warren	4 hr

Nearby

Flash Flood Warnings in Tennessee, 2012 Every flash flood warning in 2012

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.