Alert archive / Tennessee / Severe Thunderstorm Warnings in 1993

Severe Thunderstorm Warning 148, NWS Atlanta, GA

July 9, 1993Grundy County, Tennessee

NWS Atlanta, GA issued this severe thunderstorm warning at Jul 9, 1993, 11:38 AM CDT for Grundy County, Tennessee. It was in force for 52 min.

The area

The counties it named.

The facts

Issued
Jul 9, 1993, 11:38 AM CDT (16:38 UTC)
Expired
Jul 9, 1993, 12:30 PM CDT
In force
52 min
Issued by
NWS Atlanta, GA
Area
Whole counties

County Grundy County, TN

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 4.6 hours before the alert went out and 114 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 1993-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1999 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 1993-07-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -28 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
1999 J/kg
Mixed-layer CIN
-43 J/kg
Mixed-layer LCL
1088 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
-28 m²/s²
0-3 km storm-relative helicity
-20 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 
WUUS1 KCHA 091640 RRA
SVRCHA
TNC061-091730-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHATTANOOGA TN
1238 PM EDT (1138 AM CDT) FRI JUL 9 1993
 
THE NATIONAL WEATHER SERVICE IN CHATTANOOGA HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  130 PM EDT (1230 PM CDT)
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN SOUTHEAST TENNESSEE
 
   ...SOUTHERN GRUNDY COUNTY
 
AT 1235 PM EDT...1135 AM CDT...THE CHATTANOOGA WEATHER RADAR
INDICATED A SEVERE THUNDERSTORM IN SOUTHERN GRUNDY COUNTY
NEAR TRACY CITY.
 
THIS THUNDERSTORMS IS MOVING SLOWLY TO THE NORTH AND WILL
LIKELY CONTAIN HEAVY RAIN...GUSTY WINDS...DANGEROUS CLOUD
TO GROUND LIGHTNING AND HAIL.
 
 
 
IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE WEATHER IN A
STRONG BUILDING.  DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...
AND DEADLY LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS.
STAY INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.

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, Jul 9, 10:10 AM CDT, 1 hour 28 minutes before
GAZ001>015-092100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ATLANTA GA
1110 AM EDT FRI JUL 9 1993

TEMPERATURES WELL INTO THE 90S CAN BE EXPECTED ACROSS THE
STATE AGAIN THIS AFTERNOON. READINGS AROUND THE CENTURY
MARK ARE POSSILBE OVER PORTIONS OF CENTRAL GEORGIA.

THE HEAT AND HUMIDITY WILL COMBINE TO GIVE HEAT INDEX VALUES IN THE
100 TO 110 DEGREE RANGE ACROSS THE CENTRAL AND SOUTH... WITH VALUES
A FEW DEGREES COOLER ACROSS THE NORTH.

A HEAT INDEX OF 105 DEGREES IS CONSIDERED THE LEVEL AT WHICH THE
BODY HAS TROUBLE COOLING DOWN. AT THIS LEVEL SUNSTROKE... HEAT
CRAMPS OR HEAT EXHAUSTION IS LIKELY. HEATSTROKE IS ALSO POSSIBLE
WITH PROLONGED EXPOSURE OR PHYSICAL ACTIVITY.

A STATIONARY AREA OF HIGH PRESSURE OVER THE SOUTHEASTERN STATES
CONTINUE TO BE RESPONSIBLE FOR KEEPING THE HEAT AND HUMIDITY IN PLACE
OVER GEORGIA. PEOPLE PARTICIPATING IN OUTDOOR ACTIVITIES SHOULD TAKE
INTO ACCOUNT THE ADDED DISCOMFORT AND PHYSICAL STRESS DUE TO THE
HEAT AND HUMIDITY. ALSO REMEMBER THAT ACTIVITIES OR WORK TAKING
PLACE IN DIRECT MIDDAY SUNSHINE WILL HAVE AN EFFECT ON THE BODY
AS IF THE TEMPERATURE WAS 10 DEGREES WARMER.

PEOPLE SHOULD DRESS WITH LIGHT WEIGHT AND LIGHT COLORED CLOTHING...
DRINK PLENTY OF WATER OR OTHER NON-ALCOHOL FLUIDS...DONT GET TOO MUCH
SUN AND REDUCE OR ELIMINATE STRENUOUS ACTIVITIES.

PEOPLE IN PLACES WITH LITTLE VENTILATION AND THOSE IN POOR HEALTH
SHOULD TAKE PRECAUTIONS AS PROLONGED EXPOSURE TO THESE CONDITIONS
MAY LEAD TO HEAT EXHAUSTION OR POSSIBLE HEAT STROKE.
Special weather statement, Jul 9, 10:25 AM CDT, 1 hour 13 minutes before
GAZ001>015-092100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ATLANTA GA
1110 AM EDT FRI JUL 9 1993

TEMPERATURES WELL INTO THE 90S CAN BE EXPECTED ACROSS THE
STATE AGAIN THIS AFTERNOON. READINGS AROUND THE CENTURY
MARK ARE POSSILBE OVER PORTIONS OF CENTRAL GEORGIA.

THE HEAT AND HUMIDITY WILL COMBINE TO GIVE HEAT INDEX VALUES IN THE
100 TO 110 DEGREE RANGE ACROSS THE CENTRAL AND SOUTH... WITH VALUES
A FEW DEGREES COOLER ACROSS THE NORTH.

A HEAT INDEX OF 105 DEGREES IS CONSIDERED THE LEVEL AT WHICH THE
BODY HAS TROUBLE COOLING DOWN. AT THIS LEVEL SUNSTROKE... HEAT
CRAMPS OR HEAT EXHAUSTION IS LIKELY. HEATSTROKE IS ALSO POSSIBLE
WITH PROLONGED EXPOSURE OR PHYSICAL ACTIVITY.

A STATIONARY AREA OF HIGH PRESSURE OVER THE SOUTHEASTERN STATES
CONTINUE TO BE RESPONSIBLE FOR KEEPING THE HEAT AND HUMIDITY IN PLACE
OVER GEORGIA. PEOPLE PARTICIPATING IN OUTDOOR ACTIVITIES SHOULD TAKE
INTO ACCOUNT THE ADDED DISCOMFORT AND PHYSICAL STRESS DUE TO THE
HEAT AND HUMIDITY. ALSO REMEMBER THAT ACTIVITIES OR WORK TAKING
PLACE IN DIRECT MIDDAY SUNSHINE WILL HAVE AN EFFECT ON THE BODY
AS IF THE TEMPERATURE WAS 10 DEGREES WARMER.

PEOPLE SHOULD DRESS WITH LIGHT WEIGHT AND LIGHT COLORED CLOTHING...
DRINK PLENTY OF WATER OR OTHER NON-ALCOHOL FLUIDS...DONT GET TOO MUCH
SUN AND REDUCE OR ELIMINATE STRENUOUS ACTIVITIES.

PEOPLE IN PLACES WITH LITTLE VENTILATION AND THOSE IN POOR HEALTH
SHOULD TAKE PRECAUTIONS AS PROLONGED EXPOSURE TO ~THESE CONDITIONS
MAY LEAD TO HEAT EXHAUSTION OR POSSIBLE HEAT STROKE.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 9, 12:31 PM CDTSevere Thunderstorm WarningFFCSequatchie44 min
Jul 9, 3:35 PM CDTSevere Thunderstorm WarningFFCBradley55 min

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.