Alert archive / Tennessee / Flash Flood Warnings in 1998

Flash Flood Warning 65, NWS Morristown, TN

May 7, 1998Grainger County, Knox County, Tennessee

NWS Morristown, TN issued this flash flood warning at May 7, 1998, 2:05 PM EDT for Grainger County, Knox 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 counties it named.

The facts

Issued
May 7, 1998, 2:05 PM EDT (18:05 UTC)
Expired
May 7, 1998, 5:10 PM EDT
In force
3 hr
Issued by
NWS Morristown, TN
Area
Whole counties

Counties Grainger County, TN, Knox County, TN

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 6.1 hours before the alert went out and 258 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 1998-05-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Nashville Metro, TN at 12:00Z on 1998-05-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 413 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1286 m above ground
0-6 km bulk shear
63 kt
0-1 km storm-relative helicity
413 m²/s²
0-3 km storm-relative helicity
416 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 
TTAA00 KMRX 071803
FFWMRX
TNC057-093-072110-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE KNOXVILLE/TRI-CITIES TN
205 PM EDT THU MAY 7 1998

THE NATIONAL WEATHER SERVICE IN KNOXVILLE/TRI-CITIES HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHERN GRAINGER COUNTY IN EASTERN TENNESSEE
  NORTHERN KNOX COUNTY IN EASTERN TENNESSEE

* UNTIL 510 PM EDT

* AT AT 204 PM EDT... NATIONAL WEATHER SERVICE DOPPLER RADAR
  INDICATED THAT CLUSTERS OF THUNDERSTORMS WITH VERY HEAVY RAIN WERE
  LOCATED OVER NORHTERN KNOX AND SOUTHERN GRAINGER COUNTIES... MOVING
  EAST AT 30 MPH.

* EXCESSIVE RAINFALL AT THE RATE OF TOTAL RAINFALL 2 INCHES WILL
  PRODUCE FLOODING ACROSS NORTHERN KNOX AND SOUTHERN GRAINGER
  COUNTIES THROUGH 510 PM EDT.

DON'T DRIVE ACROSS FLOODED ROADS! MOST FLASH FLOOD DEATHS OCCUR IN
AUTOMOBILES.

PDK

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Morristown, TN wrote its last area forecast discussion before this flash flood warning went out at May 7, 10:16 AM EDT, 3 hours 49 minutes earlier.

Area forecast discussion, May 7, 10:16 AM EDT, 3 hours 49 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KNOXVILLE/TRI-CITIES TN
1000 AM THU MAY 7 1998

ZONE FORECASTS SEEM TO BE ON TRACK.  KMRX AND KHTX 88DS SHOWING
A BAND OF LIGHT TO MODERATE SHOWERS REMAINING OVER MUCH OF EAST TN AND
SOUTHWEST NC.  PRECIPITATION WILL ENTER EXTREME NORTHEAST TN AND
SOUTHWEST VA SHORTLY.  SEVERE STORMS THAT OCCURRED THIS MORNING TO OUR
WEST AHEAD OF A SURFACE WARM FRONT DISSIPATED AS THEY MOVED INTO A
MORE STABLE AIRMASS.  CONDITIONS MORE FAVORABLE FOR STRONG TO SEVERE
THUNDERSTORMS OVER CWA THIS AFTERNOON AND EVENING AS A SURFACE COLD
FRONT CURRENTLY IN WEST TN MOVES ACROSS THE STATE.  STRONGEST STORMS
SHOULD BE OVER THE SOUTHERN HALF OF THE CWA WHERE SURFACE DEW POINTS
ARE GREATEST AND ALSO CLOSER TO LEFT EXIT REGION OF THE 250MB JET.
MODIFIED BNA 12Z SOUNDING SHOWED CAPE AT 2500...HELICITY OF 288...
AND LI OF -6.  MODELS SHOWING STRONG MOISTURE CONVERGENCE AT 18Z THIS
AFTERNOON AHEAD OF FRONT.  PRECIPITABLE WATER AT 1.07 INCHES SO HEAVY
RAIN MAY CAUSE FLOOD PROBLEMS TOO.

RDU AND CRW...NO CHANGES RECOMMENDED.

GH

In the hours before

Special weather statement, May 7, 12:44 PM EDT, 1 hour 21 minutes before
NCZ060-061-TNZ012>018-034>047-066>074-083>087-099>102-VAZ001-002-005-
006-008-080445-

AREA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE KNOXVILLE/TRI-CITIES TN
1244 PM EDT THU MAY 7 1998

...THERE A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING
ACROSS SOUTHEAST TENNESSEE AND EXTREME SOUTHWEST NORTH CAROLINA AND A SLIGHT
RISK OF SEVERE THUNDERSTORMS OVER NORTHEAST TENNESSEE AND EXTREME SOUTHWEST
VIRGINIA...

A LOW PRESSURE SYSTEM WILL MOVE EAST ACROSS TENNESSEE TODAY PULLING WARM AND
MOIST AIR INTO THE REGION MAKING THE ATMOSPHERE VERY UNSTABLE.  THE
COMBINATION OF STRONG SOUTHERLY WINDS AT THE SURFACE AND A STRONG WESTERLY
JET STREAM WILL INCREASE THE THREAT FOR THE DEVELOPMENT OF TORNADOES.

ALTHOUGH THERE IS A RISK OF SEVERE THUNDERSTORMS ACROSS THE ENTIRE AREA
INCLUDING SOUTHWEST VIRGINIA...EAST TENNESSEE AND SOUTHWEST NORTH CAROLINA...
THE BEST CHANCE FOR SEVERE STORMS WILL BE ACROSS SOUTHEAST TENNESSEE AND
EXTREME SOUTHWEST NORTH CAROLINA...GENERALLY SOUTH OF A LINE EXTENDING FROM
CROSSVILLE...TO MADISONVILLE...TO HAYESVILLE NORTH CAROLINA.

THE MAIN SEVERE THREAT WITH THESE STORMS WILL BE STRONG DAMAGING WINDS AND
LARGE HAIL...BUT TORNADOES ARE ALSO POSSIBLE.

RESIDENTS ACROSS SOUTHWEST VIRGINIA...EAST TENNESSEE AND EXTREME SOUTHWEST
NORTH CAROLINA SHOULD STAY TUNED TO NOAA WEATHER RADIO OR THE MEDIA
FOR ANY FURTHER STATEMENTS FROM THE NATIONAL WEATHER SERVICE.  EMERGENCY
MANAGEMENT OFFICIALS AND STORM SPOTTERS SHOULD BE PREPARED FOR POSSIBLE
ACTIVATION TODAY.

GH

The office that day

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

IssuedProductOfficeCountiesLasted
May 7, 1:25 PM EDTSevere Thunderstorm WarningMRXScott65 min
May 7, 1:49 PM EDTSevere Thunderstorm WarningMRXHamilton46 min
May 7, 1:55 PM EDTSevere Thunderstorm WarningMRXCampbell65 min
May 7, 2:10 PM EDTSevere Thunderstorm WarningMRXBradley50 min
May 7, 2:18 PM EDTSevere Thunderstorm WarningMRXClaiborne47 min
May 7, 2:25 PM EDTSevere Thunderstorm WarningMRXGreene, Hamblen50 min
May 7, 2:31 PM EDTSevere Thunderstorm WarningMRXPolk49 min
May 7, 2:37 PM EDTTornado WarningMRXBradley, Polk33 min
May 7, 2:44 PM EDTSevere Thunderstorm WarningMRXJefferson, Knox66 min
May 7, 2:55 PM EDTFlash Flood WarningMRXGreene, Hamblen2 hr
May 7, 3:07 PM EDTTornado WarningMRXJefferson33 min
May 7, 3:13 PM EDTSevere Thunderstorm WarningMRXUnicoi, Washington32 min
May 7, 3:13 PM EDTTornado WarningMRXPolk47 min
May 7, 3:18 PM EDTSevere Thunderstorm WarningMRXHancock47 min
May 7, 3:31 PM EDTTornado WarningMRXKnox, Sevier64 min
May 7, 3:33 PM EDTSevere Thunderstorm WarningMRXCocke62 min
May 7, 3:34 PM EDTSevere Thunderstorm WarningMRXClaiborne66 min
May 7, 3:41 PM EDTFlash Flood WarningMRXCocke, Jefferson3 hr
May 7, 3:45 PM EDTSevere Thunderstorm WarningMRXJefferson65 min
May 7, 3:53 PM EDTSevere Thunderstorm WarningMRXGreene47 min
May 7, 4:29 PM EDTSevere Thunderstorm WarningMRXHamilton, Meigs, Rhea46 min
May 7, 4:39 PM EDTSevere Thunderstorm WarningMRXPolk36 min
May 7, 4:47 PM EDTSevere Thunderstorm WarningMRXMcMinn48 min
May 7, 4:54 PM EDTSevere Thunderstorm WarningMRXHawkins, Sullivan46 min
May 7, 5:05 PM EDTTornado WarningMRXMcMinn50 min
May 7, 5:07 PM EDTSevere Thunderstorm WarningMRXGreene48 min
May 7, 5:13 PM EDTSevere Thunderstorm WarningMRXHamilton, Meigs, Rhea32 min
May 7, 5:23 PM EDTSevere Thunderstorm WarningMRXMonroe32 min
May 7, 5:54 PM EDTSevere Thunderstorm WarningMRXMonroe, Polk36 min
May 7, 5:55 PM EDTSevere Thunderstorm WarningMRXBlount, Knox50 min
May 7, 6:00 PM EDTSevere Thunderstorm WarningMRXJefferson50 min
May 7, 6:05 PM EDTSevere Thunderstorm WarningMRXPolk35 min
May 7, 6:22 PM EDTSevere Thunderstorm WarningMRXCocke, Sevier33 min
May 7, 6:48 PM EDTSevere Thunderstorm WarningMRXLoudon, Roane47 min
May 7, 7:03 PM EDTSevere Thunderstorm WarningMRXGreene, Hamblen47 min
May 7, 7:36 PM EDTSevere Thunderstorm WarningMRXSullivan, Washington34 min
May 7, 7:45 PM EDTSevere Thunderstorm WarningMRXCocke, Jefferson50 min

Nearby

Flash Flood Warnings in Tennessee, 1998Every flash flood warning in 1998

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.