Alert archive / Florida / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 138, NWS Miami, FL

August 20, 1997Collier County, Hendry County, Florida

NWS Miami, FL issued this severe thunderstorm warning at Aug 20, 1997, 5:12 PM EDT for Collier County, Hendry County, Florida. It was in force for 48 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 20, 1997, 5:12 PM EDT (21:12 UTC)
Expired
Aug 20, 1997, 6:00 PM EDT
In force
48 min
Issued by
NWS Miami, FL
Area
Whole counties

Counties Collier County, FL, Hendry County, FL

The nearest sounding before it

Miami, FL (KMFL), launched 12:00Z, 9.2 hours before the alert went out and 113 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, Miami, FL at 12:00Z on 1997-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2545 joules per kilogram.LCLEL10008507005003002001001 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, Miami, FL at 12:00Z on 1997-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 2 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
2545 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
739 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
2 m²/s²
0-3 km storm-relative helicity
13 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 KMIA 202115 RRA
SVRMIA
FLC051-021-202200-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MIAMI FL
512 PM EDT WED AUG 20 1997
 
THE NATIONAL WEATHER SERVICE IN MIAMI HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  600 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTH FLORIDA
 
   ...SOUTHWESTERN HENDRY COUNTY
 
AND IN SOUTHWEST FLORIDA
 
   ...NORTHERN COLLIER COUNTY
 
AT 515 PM...MIAMI DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM OVER
EXTREME NORTHERN COLLIER COUNTY JUST NORTH OF CORKSCREW SWAMP. THIS
STORM IS NEARLY STATIONARY. RADAR INDICATES THE POSSIBILITY OF
LARGE HAIL IN THIS STORM. THIS STORM WILL AFFECT THE COMMUNITIES OF
FELDA AND CORKSCREW THROUGH 6 PM.
 
DAMAGING WIND IN EXCESS OF 55 MPH...LARGE HAIL...VERY HEAVY RAIN...
AND DEADLY LIGHTNING ARE ALL POSSIBLE IN A SEVERE THUNDERSTORM. SEEK
SHELTER IN A STRONG BUILDING. STAY AWAY FROM WINDOWS. DO NOT USE
TELEPHONES OR ELELCTRICAL APPLIANCES.

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

Local storm report, Aug 20, 5:00 PM EDT, 12 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MIAMI FL
500 PM EDT WED AUG 20 1997

TIME(EDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0430 PM    POMPANO BEACH             FL   1.00 INCH HAIL
08/20/97   BROWARD                        63RD AND SW 19TH STREET.
                                          NO DAMAGE.

0433 PM    FT LAUDERDALE EXEC ARPT   FL   52 MPH TSTM GUST
08/20/97   BROWARD                        REPORT FROM AUTOMATED
                                          REPORTING SITE AT FT
                                          LAUDERDALE EXECUTIVE
                                          AIRPORT (FXE).

0440 PM    LAUDERHILL                FL   .75 INCH HAIL
08/20/97   BROWARD                        DIME SIZED HAIL REPORTED
                                          BY SPOTTER. ALSO ESTIMATED
                                          40-50 MPH WIND GUST. AT
                                          44TH AND UNIVERSITY.
Local storm report, Aug 20, 5:05 PM EDT, 7 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MIAMI FL
500 PM EDT WED AUG 20 1997

TIME(EDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0430 PM    POMPANO BEACH             FL   1.00 INCH HAIL
08/20/97   BROWARD                        63RD AND SW 19TH STREET.
                                          NO DAMAGE.

0433 PM    FT LAUDERDALE EXEC ARPT   FL   52 MPH TSTM GUST
08/20/97   BROWARD                        REPORT FROM AUTOMATED
                                          REPORTING SITE AT FT
                                          LAUDERDALE EXECUTIVE
                                          AIRPORT (FXE).

0440 PM    LAUDERHILL                FL   .75 INCH HAIL
08/20/97   BROWARD                        DIME SIZED HAIL REPORTED
                                          BY SPOTTER. ALSO ESTIMATED
                                          40-50 MPH WIND GUST. AT
                                          44TH AND UNIVERSITY.

The office that day

Everything else NWS Miami, FL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 20, 4:00 PM EDTSevere Thunderstorm WarningMFLBroward45 min
Aug 20, 4:19 PM EDTSevere Thunderstorm WarningMFLBroward41 min

Nearby

Severe Thunderstorm Warnings in Florida, 1997Every severe thunderstorm warning in 1997

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.