Alert archive / Tennessee / Severe Thunderstorm Warnings in 1989

Severe Thunderstorm Warning 68, NWS Atlanta, GA

May 20, 1989Hamilton County, Rhea County, Tennessee

NWS Atlanta, GA issued this severe thunderstorm warning at May 20, 1989, 6:08 AM EDT for Hamilton County, Rhea County, Tennessee. It was in force for 52 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
May 20, 1989, 6:08 AM EDT (10:08 UTC)
Expired
May 20, 1989, 7:00 AM EDT
In force
52 min
Issued by
NWS Atlanta, GA
Area
Whole counties

Counties Hamilton County, TN, Rhea County, TN

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

What was reported inside it

TimeReportWhereRemark
May 20, 6:30 AM EDTThunderstorm Wind 0Hamilton, TN

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 00:00Z, 10.1 hours before the alert went out and 162 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 1989-05-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 999 joules per kilogram.LCLLFCEL10008507005003002001001 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 1989-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 210 square meters per square second.193958Sfc1 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
999 J/kg
Mixed-layer CIN
-18 J/kg
Mixed-layer LCL
1198 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
210 m²/s²
0-3 km storm-relative helicity
414 m²/s²
Significant tornado parameter
1.4
Supercell composite
6.5

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KCHA 201011
SVRCHA
TNC065-143-201100-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHATTANOOGA TN
608 AM EDT SAT MAY 20 1989
 
THE NATIONAL WEATHER SERVICE IN CHATTANOOGA HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  700 AM EDT
FOR PEOPLE IN THE FOLLOWING COUNTIES...
 
IN SOUTHEAST TENNESSEE
          ...NORTHERN HAMILTON...SOUTHERN RHEA
 
RADAR INDICATED SEVERE THUNDERSTORMS MOVING INTO SOUTHERN RHEA
AND NORTHERN HAMILTON COUNTIES OF SOUTHEAST TENNESSEE. THIS INCLUDES
DAYTON...SAIL CREEK AND SODDY DAISY.  REPORTS INDICATE THAT THIS STORM
HAS STRONG WINDS THAT HAS BLOWN DOWN LARGE TREES AS IT PASSES THROUGH
BLEDSOE COUNTY.
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

The office that day

Everything else NWS Atlanta, GA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 20, 5:26 AM EDTSevere Thunderstorm WarningFFCBledsoe, Van Buren64 min
May 20, 6:29 AM EDTSevere Thunderstorm WarningFFCBradley, Hamilton61 min

Nearby

Severe Thunderstorm Warnings in Tennessee, 1989Every severe thunderstorm warning in 1989

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.