Alert archive / Florida / Severe Thunderstorm Warnings in 1993

Severe Thunderstorm Warning 5, NWS Melbourne, FL

February 12, 1993Palm Beach County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Feb 12, 1993, 6:50 AM EST for Palm Beach County, Florida. It was in force for 55 min.

The area

The counties it named.

The facts

Issued
Feb 12, 1993, 6:50 AM EST (11:50 UTC)
Expired
Feb 12, 1993, 7:45 AM EST
In force
55 min
Issued by
NWS Melbourne, FL
Area
Whole counties

County Palm Beach County, FL

The nearest sounding before it

Cape Canaveral, FL (KXMR), launched 00:00Z, 11.8 hours before the alert went out and 203 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, Cape Canaveral, FL at 00:00Z on 1993-02-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1449 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, Cape Canaveral, FL at 00:00Z on 1993-02-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 94 square meters per square second.1939587897Sfc1 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
1449 J/kg
Mixed-layer CIN
-31 J/kg
Mixed-layer LCL
813 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
94 m²/s²
0-3 km storm-relative helicity
116 m²/s²
Significant tornado parameter
0.7
Supercell composite
4.7

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KPBI 121150
SVRPBI
FLC099-121245-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE WEST PALM BEACH FL
650 AM EST FRI FEB 12 1993
 
THE NATIONAL WEATHER SERVICE IN WEST PALM BEACH HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  745 AM EST
FOR THE FOLLOWING LOCATIONS......
 
IN SOUTHEAST FLORIDA
 
   ...SOUTHERN PALM BEACH COUNTY
 
AND THE ADJACANT WATERS OF THE SOUTHEAST FLORIDA COAST
 
AT 645 AM NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE THUNDERSTORM
OVER EXTREME NORTH CENTRAL BROWARD COUNTY. THIS STORM WAS MOVING
NORTHEAST NEAR 30 MILES AN HOUR AND WILL MOVE INTO SOUTHERN PALM BEACH
COUNTY DURING THE NEXT HALF HOUR.
 
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 A.REAS WHERE WATER COVERS THE ROAD.
 
 
 
NNNN

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, Feb 12, 1:00 AM EST, 5 hours 50 minutes before
FLZ017-120700-

SPECIAL EAST CENTRAL FLORIDA WEATHER UPDATE
NATIONAL WEATHER SERVICE MELBOURNE FL
101 AM EST FRI FEB 12 1993

...STRONG THUNDERSTORMS OVER SOUTH BREVARD AND INDIAN RIVER
COUNTIES...

AT 1255 AM...A BROKEN 60 MILE WIDE BAND OF SHOWERS AND STRONG
THUNDERSTORMS EXTENDED FROM 50 MILES EAST OF DAYTONA BEACH TO THE
COAST BETWEEN MELBOURNE AND SEBASTIAN INLET...THEN SOUTHWEST TO OVER
SOUTHWEST FLORIDA. THE STRONGEST CLUSTER OF ACTIVITY WAS JUST MOVING
OFFSHORE BETWEEN COCOA BEACH AND SEBASTIAN.

THE INDIVIDUAL THUNDERSTORMS WERE RACING NORTHEAST AT 30 TO 40 MPH
WHILE THE BAND MOVED EAST AT 20 MPH.

THESE THUNDERSTORMS WERE PRODUCING VERY HEAVY RAIN...DANGEROUS
LIGHTNING...A`ND STRONG GUSTY WINDS. MARINERS CAN EXPECT ROUGH AND
CONFUSED SEAS IN AND NEAR THESE THUNDERSTORMS.

ELSEWHERE...SCATTERED SHOWERS AND PATCHES OF RAIN WERE OVER MOST OF
THE REST OF EAST CENTRAL FLORIDA.

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 12, 11:53 AM ESTSevere Thunderstorm WarningMLBSaint Lucie52 min

Nearby

Severe Thunderstorm Warnings in Florida, 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.