Alert archive / Tennessee / Severe Thunderstorm Warnings in 1993

Severe Thunderstorm Warning 220, NWS Atlanta, GA

August 20, 1993Bradley County, McMinn County, Polk County, Tennessee

NWS Atlanta, GA issued this severe thunderstorm warning at Aug 20, 1993, 5:40 PM EDT for Bradley County, McMinn County, Polk County, Tennessee. It was in force for 50 min.

The area

The counties it named.

The facts

Issued
Aug 20, 1993, 5:40 PM EDT (21:40 UTC)
Expired
Aug 20, 1993, 6:30 PM EDT
In force
50 min
Issued by
NWS Atlanta, GA
Area
Whole counties

Counties Bradley County, TN, McMinn County, TN, Polk County, TN

The nearest sounding before it

Athens Municipal, GA (KAHN), launched 12:00Z, 9.7 hours before the alert went out and 190 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, Athens Municipal, GA at 12:00Z on 1993-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1126 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, Athens Municipal, GA at 12:00Z on 1993-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 11 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
1126 J/kg
Mixed-layer CIN
-32 J/kg
Mixed-layer LCL
831 m above ground
0-6 km bulk shear
7 kt
0-1 km storm-relative helicity
11 m²/s²
0-3 km storm-relative helicity
34 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 202139 RRA
SVRCHA
TNC011-107-139-202230-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHATTANOOGA TN
540 PM EDT FRI AUG 20 1993
 
THE NATIONAL WEATHER SERVICE IN CHATTANOOGA HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  630 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTHEAST TENNESSEE
 
   ...BRADLEY COUNTY...SOUTHERN MCMINN COUNTY...POLK COUNTY
 
AT 535PM EDT WEATHER RADAR INDICATED SEVERE THUNDERSTORMS OVER
SOUTHERN MCMINN...NORTHERN AND CENTRAL BRADLEY AND NORTHERN
POLK COUNTIES OF SOUTHEAST TENNESSEE.
 
THE THUNDERSTORMS ARE MOVING TOWARD 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.
 
 
n

What forecasters said that day

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

In the hours before

Special weather statement, Aug 20, 5:30 PM EDT, 10 minutes before
GAZ001>GAZ003-202300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ATLANTA GA
530 PM EDT WED AUG 18 1993

AT 525 PM EDT WEATHER SERVICE RADARS SHOWED WIDELY SCATTERED THUNDER-
STORMS WERE DEVELOPING OVER PARTS OF NORTHERN GEORGIA. THE STRONGEST
THUNDERSTORM WAS OCCURRING OVER THE NORTHWESTERN PORTION OF CHATTOOGA
COUNTY NEAR CLOUDLAND. THESE STORMS WERE MOVING SOUTHEAST AT NEAR 20
MILES AN HOUR.

NORTHWEST GEORGIA'S THUNDERSTORMS HAVE DEVELOPED AHEAD OF A LARGER AREA
OF SHOWERS AND THUNDERSTORMS THAT STRETCHED FROM NORTH CAROLINA WEST
ACROSS TENNESSEE. ANOTHER AREA OF THUNDERSTORMS HAD ALSO DEVELOPED OVER
NORTHERN ALABAMA. MOVEMENT ON ALL OF THESE STORMS WAS TO THE SOUTHEAST.
WITH THE AFTERNOON HEAT AS FUEL...ADDITIONAL THUNDERSTORMS MAY DEVELOP
ACROSS NORTH GEORGIA DURING THE REMAINDER OF DAY AND THIS EVENING.

RESIDENTS OF NORTH GEORGIA SHOULD REMAIN ALERT. BE PREPARED TO QUICKLY
SEEK SHELTER IF STORMS DEVELOP OR MOVE INTO YBOUR AREA.

Nearby

Severe Thunderstorm Warnings in Tennessee, 1993Every severe thunderstorm warning in 1993

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.