Alert archive / Tennessee / Flash Flood Warnings in 2003

Flash Flood Warning 13, NWS Morristown, TN

August 11, 2003Sevier County, Tennessee

NWS Morristown, TN issued this flash flood warning at Aug 11, 2003, 8:41 PM EDT for Sevier County, Tennessee. 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: Aug 11, 2003, 8:41 PM EDT (00:41 UTC)
Expired: Aug 11, 2003, 10:45 PM EDT
In force: 2 hr
Issued by: NWS Morristown, TN
Area: Counties, with a storm outline in the text

County Sevier County, TN

The radar

The Knoxville radar (KMRX), 37 km from the middle of the area, began a volume at 00:42 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 00:00Z, 0.7 hours before the alert went out and 273 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: 755 J/kg
Mixed-layer CIN: -26 J/kg
Mixed-layer LCL: 824 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: -23 m²/s²
0-3 km storm-relative helicity: 13 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.

000 
WGUS54 KMRX 120045
FFWMRX
TNC155-120245-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MORRISTOWN TN
841 PM EDT MON AUG 11 2003

THE NATIONAL WEATHER SERVICE IN MORRISTOWN HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SEVIER COUNTY IN EAST TENNESSEE

* UNTIL 1045 PM EDT

* AT 836 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  A LINE OF THUNDERSTORM WITH VERY HEAVY RAIN NEAR SEVIERVILLE.  THE
  LINE OF THUNDERSTORMS PRODUCING THE FLASH FLOOD WAS MOVING
  NORTHEAST AT 5 MPH.

* LOCATIONS IN THE WARNING INCLUDE...
  PIGEON FORGE...MCMAHAN...SEVIERVILLE...HARRISBURG

NATIONAL WEATHER SERVICE DOPPLER RADAR HAS ESTIMATED THAT 2 TO 3 
INCHES OF RAIN HAVE FALLEN OVER THE PAST HOUR. AN ADDITIONAL ONE TO 
TWO INCHES OF RAIN ARE EXPECTED OVER THE NEXT HOUR.

AT 820 PM EDT A TRAINED WEATHER SPOTTER REPORTED WATER OVER HIGHWAY 
321 WHERE IT ENTERS WEARS VALLEY.  ANOTHER AREA ESPECIALLY LIKELY TO 
BE EXPERIENCING FLOODING IS NORTHEAST SEVIER COUNTY...FROM 
SEVIERVILLE OVER TOWARDS DOUGLAS DAM.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODS AND FLASH FLOODS. IF FLASH FLOODING IS OBSERVED ACT
QUICKLY. MOVE UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS.

LAT...LON 3586 8376 3570 8357 3590 8332 3592 8349
          3600 8359

$$

SP

1 follow-up statement

000 
WGUS74 KMRX 120213
FFSMRX
TNC155-120245-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MORRISTOWN TN
1011 PM EDT MON AUG 11 2003

...THE FLASH FLOOD WARNING FOR SEVIER COUNTY HAS BEEN CANCELED...

AT 1011 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED THE
RAINFALL HAS ENDED ACROSS THE WARNED AREA...AND THE FLOOD THREAT WAS 
DIMINISHING.  SOME MINOR FLOODING MAY CONTINUE...BUT THE THREAT OF 
SERIOUS FLOODING HAS ENDED.  THEREFORE THE FLASH FLOOD WARNING HAS 
BEEN CANCELED.

AT 1011 PM EDT LOCAL LAW ENFORCEMENT REPORTED THAT THE WATER WAS 
RECEDING.  HOWEVER...THERE MAY STILL BE LOCALIZED AREAS OF HIGH 
WATER THAT MAY BE DANGEROUS.  PLEASE BE CAREFUL.

BE ESPECIALLY CAUTIOUS AT NIGHT...WHEN THE DANGERS OF FLOODING ARE
HARDER TO RECOGNIZE. DO NOT DRIVE WHERE WATER COVERS THE ROAD.

&

LAT...LON 3584 8373 3567 8348 3583 8329 3592 8338
          3591 8348 3597 8357

$$

SP

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 11, 8:12 PM EDT	Severe Thunderstorm Warning	MRX	Sevier	48 min

Nearby

Flash Flood Warnings in Tennessee, 2003 Every flash flood warning in 2003

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.