Alert archive / Tennessee / Flash Flood Warnings in 2012

Flash Flood Warning 3, NWS Morristown, TN

April 2, 2012Knox County, Tennessee

NWS Morristown, TN issued this flash flood warning at Apr 2, 2012, 6:13 PM EDT for Knox County, Tennessee. It was in force for 3 hr. 1 report 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
Apr 2, 2012, 6:13 PM EDT (22:13 UTC)
Expired
Apr 2, 2012, 9:15 PM EDT
In force
3 hr
Issued by
NWS Morristown, TN
Area
Storm-based polygon
Flood severity
None

County Knox County, TN

The radar

The Knoxville radar (KMRX), 51 km from the middle of the area, began a volume at 22:14 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
Apr 2, 6:30 PM EDTFLASH FLOODKnoxville, TNFLOODING REPORTED WHICH RESULTED IN SOME ROAD CLOSURES AND SUBMERGED CARS NEAR DOWNTOWN.

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 12:00Z, 10.2 hours before the alert went out and 241 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, Nashville Metro, TN at 12:00Z on 2012-04-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 897 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, Nashville Metro, TN at 12:00Z on 2012-04-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 155 square meters per square second.1939Sfc1 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
897 J/kg
Mixed-layer CIN
-52 J/kg
Mixed-layer LCL
785 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
155 m²/s²
0-3 km storm-relative helicity
209 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.

071 
WGUS54 KMRX 022213
FFWMRX
TNC093-030115-
/O.NEW.KMRX.FF.W.0003.120402T2213Z-120403T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MORRISTOWN TN
613 PM EDT MON APR 2 2012

THE NATIONAL WEATHER SERVICE IN MORRISTOWN HAS ISSUED A

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

* UNTIL 915 PM EDT

* AT 606 PM EDT...DOPPLER RADAR INDICATED SLOW MOVING THUNDERSTORMS 
NEAR KNOXVILLE...WHICH HAVE PRODUCED AROUND THREE INCHES OF RAIN IN 
THE PAST HOUR NEAR EAST KNOXVILLE. ADDITIONAL RAINFALL AMOUNTS 
AROUND AN INCH OR TWO WILL BE POSSIBLE IN THE NEXT COUPLE OF HOURS. 
RAINFALL OF THIS MAGNITUDE WILL LIKELY CAUSE FLOODING OF ROADWAYS 
AND LOW LYING AREAS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. MOVE TO HIGHER GROUND.

&&

LAT...LON 3605 8404 3608 8387 3593 8375 3587 8393

$$

DMG
2 follow-up statements
677 
WGUS74 KMRX 022323
FFSMRX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MORRISTOWN TN
723 PM EDT MON APR 2 2012

TNC093-030115-
/O.CON.KMRX.FF.W.0003.000000T0000Z-120403T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
KNOX TN-
723 PM EDT MON APR 2 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 915 PM FOR KNOX 
COUNTY...

AT 718 PM EDT...SPOTTERS REPORTED FLOODING IN EAST KNOXVILLE FROM 
EARLIER RAINFALL. WHILE RAIN HAS ENDED IN EAST KNOXVILLE...RUNOFF 
FROM THE EARLIER RAINFALL WILL CONTINUE FOR THE NEXT FEW HOURS. 
DOPPLER RADAR CONTINUES TO INDICATE SLOW MOVING THUNDERSTORMS NEAR 
POWELL AND WEST KNOXVILLE...WHICH HAVE PRODUCED AROUND TWO INCHES OF 
RAIN IN THE PAST HOUR. ADDITIONAL RAINFALL AMOUNTS AROUND AN INCH OR 
TWO WILL BE POSSIBLE IN THE NEXT COUPLE OF HOURS.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

RUNOFF FROM HEAVY RAIN WILL CAUSE FLOODING OF CREEKS AND STREAMS,
URBAN AREAS, HIGHWAYS, STREETS, AND UNDERPASSES. LOW LYING PLACES
THAT NORMALLY FLOOD COULD BECOME DEATH TRAPS. IF YOU COME TO A
FLOODED OR CLOSED ROAD...TURN AROUND! DON'T DROWN! THIS IS A LIFE
THREATENING SITUATION.

TO REPORT FLOODING...PLEASE CONTACT THE NATIONAL WEATHER SERVICE 
OFFICE IN MORRISTOWN.

&&

LAT...LON 3605 8404 3608 8387 3593 8375 3587 8393

$$

DMG
459 
WGUS74 KMRX 030011
FFSMRX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MORRISTOWN TN
811 PM EDT MON APR 2 2012

TNC093-030115-
/O.CON.KMRX.FF.W.0003.000000T0000Z-120403T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
KNOX TN-
811 PM EDT MON APR 2 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 915 PM FOR KNOX 
COUNTY...

AT 805 PM...DOPPLER RADAR INDICATED THAT RAINFALL HAS ENDED ACROSS 
THE WARNED AREA...BUT RUNOFF FROM EARLIER RAINFALL WILL LIKELY 
CONTINUE TO PRODUCE SOME FLOODING FOR THE NEXT HOUR.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 3605 8404 3608 8387 3593 8375 3587 8393

$$

DMG

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 2, 5:04 PM EDTSevere Thunderstorm WarningMRXBlount, Knox, Sevier41 min
Apr 2, 5:42 PM EDTAreal Flood AdvisoryMRXBlount, Knox, Sevier2 hr

Nearby

Flash Flood Warnings in Tennessee, 2012Every 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.