Alert archive / Tennessee / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 232, NWS Atlanta, GA

July 12, 1990Hamilton County, Tennessee

NWS Atlanta, GA issued this severe thunderstorm warning at Jul 12, 1990, 4:00 PM EDT for Hamilton County, Tennessee. It was in force for 60 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
Jul 12, 1990, 4:00 PM EDT (20:00 UTC)
Expired
Jul 12, 1990, 5:00 PM EDT
In force
60 min
Issued by
NWS Atlanta, GA
Area
Whole counties

County Hamilton 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
Jul 12, 4:10 PM EDTHail 0.75Hamilton, 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 12:00Z, 8.0 hours before the alert went out and 167 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 1990-07-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 101 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 12:00Z on 1990-07-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 23 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
101 J/kg
Mixed-layer CIN
-57 J/kg
Mixed-layer LCL
717 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
44 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 KCHA 122003
SVRCHA
TNC065-122100-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHATTANOOGA TENNESSEE
400 PM EDT THU JUL 12 1990
 
THE NATIONAL WEATHER SERVICE IN CHATTANOOGA TENNESSEE HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  500 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS
 
IN SOUTHEAST TENNESSEE
 
   ...HAMILTON COUNTY
 
AT 400 PM EDT THE CHATTANOOGA WEATHER RADAR INDICATED A LINE OF
THUNDERSTORMS MOVING INTO WESTERN HAMILTON...WITH SOME OF THE
STORMS POSSIBLY SEVERE.
 
THE LINE OF THUNDERSTORMS IS MOVING TO THE SOUTHEAST AT 20
MPH.
 
 
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
Jul 12, 4:31 PM EDTSevere Thunderstorm WarningFFCBradley59 min

Nearby

Severe Thunderstorm Warnings in Tennessee, 1990Every severe thunderstorm warning in 1990

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.