Alert archive / Tennessee / Flash Flood Warnings in 1998

Flash Flood Warning 39, NWS Morristown, TN

April 18, 1998Knox County, Union County, Tennessee

NWS Morristown, TN issued this flash flood warning at Apr 18, 1998, 9:46 PM EDT for Knox County, Union County, Tennessee. It was in force for 5 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
Apr 18, 1998, 9:46 PM EDT (01:46 UTC)
Expired
Apr 19, 1998, 2:50 AM EDT
In force
5 hr
Issued by
NWS Morristown, TN
Area
Whole counties

Counties Knox County, TN, Union County, TN

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 00:00Z, 1.8 hours before the alert went out and 244 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 00:00Z on 1998-04-19Temperature 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 00:00Z on 1998-04-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 24 square meters per square second.1939587897117Sfc1 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
498 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
24 m²/s²
0-3 km storm-relative helicity
28 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 190147
FFWMRX
TNC093-105-123-173-190650-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE KNOXVILLE/TRI-CITIES TN
946 PM EDT SAT APR 18 1998

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

* FLASH FLOOD WARNING FOR...
  KNOX COUNTY IN EASTERN TENNESSEE
  LOUDON COUNTY IN EASTERN TENNESSEE
  MONROE COUNTY IN EASTERN TENNESSEE
  UNION COUNTY IN EASTERN TENNESSEE

* UNTIL 250 AM EDT

* AT 945 PM EDT... NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  THAT CLUSTERS OF THUNDERSTORMS WITH VERY HEAVY RAIN WERE LOCATED
  OVER ALL THE WARNED COUNTIES... MOVING NORTHEAST 45 MPH.

* EXCESSIVE RAINFALL AT THE RATE OF ONE HALF TO THREE QUARTERS INCH
  PER H.OUR WILL PRODUCE FLOODING ACROSS ANY LOCATION WITHIN THE
  WARNED COUNTIES THROUGH 250 AM EDT.

  BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
  DANGER OF FLOODING.

HSA/CAC

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 Apr 18, 9:20 PM EDT, 26 minutes earlier.

Area forecast discussion, Apr 18, 9:20 PM EDT, 26 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KNOXVILLE/TRI-CITIES TN
920 PM EDT SAT APR 18 1998

ON GOING SEVERE WEATHER HAVE NOT LOOKED AT ANY NEW DATA...BUT ONGOING
FORECAST LOOKS GOOD.

PDK

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 18, 8:07 PM EDTFlash Flood WarningMRXRhea4 hr
Apr 18, 8:24 PM EDTFlash Flood WarningMRXHamilton, Meigs6 hr
Apr 18, 8:24 PM EDTFlash Flood WarningMRXRoane6 hr
Apr 18, 8:33 PM EDTSevere Thunderstorm WarningMRXRoane47 min
Apr 18, 8:35 PM EDTSevere Thunderstorm WarningMRXHamilton, Meigs, Rhea65 min
Apr 18, 8:50 PM EDTFlash Flood WarningMRXAnderson, Campbell, Scott5 hr
Apr 18, 8:50 PM EDTFlash Flood WarningMRXClaiborne5 hr
Apr 18, 9:01 PM EDTSevere Thunderstorm WarningMRXMcMinn34 min
Apr 18, 9:09 PM EDTSevere Thunderstorm WarningMRXAnderson51 min
Apr 18, 9:13 PM EDTFlash Flood WarningMRXBradley, McMinn, Polk6 hr
Apr 18, 9:28 PM EDTSevere Thunderstorm WarningMRXKnox, Union47 min
Apr 18, 9:46 PM EDTFlash Flood WarningMRXLoudon, Monroe5 hr
Apr 18, 9:59 PM EDTSevere Thunderstorm WarningMRXBradley, Hamilton, Polk51 min
Apr 18, 10:14 PM EDTSevere Thunderstorm WarningMRXClaiborne, Grainger31 min
Apr 18, 10:29 PM EDTSevere Thunderstorm WarningMRXMonroe46 min
Apr 18, 10:30 PM EDTSevere Thunderstorm WarningMRXHancock35 min
Apr 18, 10:41 PM EDTTornado WarningMRXMonroe49 min
Apr 18, 10:48 PM EDTSevere Thunderstorm WarningMRXPolk32 min
Apr 18, 10:58 PM EDTSevere Thunderstorm WarningMRXGrainger, Hamblen, Jefferson32 min
Apr 18, 11:04 PM EDTFlash Flood WarningMRXCocke, Grainger, Hamblen, Hawkins, Jefferson5 hr
Apr 18, 11:04 PM EDTFlash Flood WarningMRXCumberland, Morgan5 hr
Apr 18, 11:04 PM EDTFlash Flood WarningMRXHancock5 hr
Apr 18, 11:04 PM EDTFlash Flood WarningMRXRhea5 hr
Apr 18, 11:04 PM EDTFlash Flood WarningMRXBlount, Sevier5 hr
Apr 18, 11:26 PM EDTSevere Thunderstorm WarningMRXMonroe34 min
Apr 18, 11:41 PM EDTSevere Thunderstorm WarningMRXBlount34 min
Apr 19, 1:47 AM EDTFlash Flood WarningMRXGrainger, Hamblen, Hancock, Hawkins8 hr
Apr 19, 1:47 AM EDTFlash Flood WarningMRXBradley, Hamilton, McMinn, Meigs, Polk8 hr
Apr 19, 1:47 AM EDTFlash Flood WarningMRXBlount, Loudon, Monroe8 hr
Apr 19, 1:47 AM EDTFlash Flood WarningMRXCumberland, Rhea, Roane8 hr
Apr 19, 1:47 AM EDTFlash Flood WarningMRXAnderson, Campbell, Claiborne, Scott, Union8 hr
Apr 19, 1:47 AM EDTFlash Flood WarningMRXFentress, Morgan8 hr
Apr 19, 1:47 AM EDTFlash Flood WarningMRXJefferson, Knox, Sevier8 hr
Apr 19, 1:47 AM EDTFlash Flood WarningMRXCocke8 hr
Apr 19, 3:19 AM EDTSevere Thunderstorm WarningMRXSevier61 min
Apr 19, 7:03 AM EDTFlash Flood WarningMRXCarter, Johnson, Sullivan3 hr
Apr 19, 7:03 AM EDTFlash Flood WarningMRXGreene, Unicoi, Washington3 hr
Apr 19, 9:39 AM EDTFlash Flood WarningMRXBlount, Sevier8 hr
Apr 19, 9:45 AM EDTFlash Flood WarningMRXKnox, Loudon, McMinn, Monroe8 hr
Apr 19, 9:45 AM EDTFlash Flood WarningMRXClaiborne, Grainger, Hancock, Union8 hr

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.