Alert archive / Florida / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 14, NWS Miami, FL

August 11, 1990Broward County, Florida

NWS Miami, FL issued this severe thunderstorm warning at Aug 11, 1990, 4:16 PM EDT for Broward County, Florida. It was in force for 44 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
Aug 11, 1990, 4:16 PM EDT (20:16 UTC)
Expired
Aug 11, 1990, 5:00 PM EDT
In force
44 min
Issued by
NWS Miami, FL
Area
Whole counties

County Broward County, FL

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
Aug 11, 4:43 PM EDTThunderstorm Wind 0Broward, FL

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

Key West, FL (KEYW), launched 12:00Z, 8.3 hours before the alert went out and 218 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, Key West, FL at 12:00Z on 1990-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2150 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, Key West, FL at 12:00Z on 1990-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 14 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
2150 J/kg
Mixed-layer CIN
-9 J/kg
Mixed-layer LCL
933 m above ground
0-6 km bulk shear
3 kt
0-1 km storm-relative helicity
14 m²/s²
0-3 km storm-relative helicity
5 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 112017
SVRMIA
FLC011-112100-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MIAMI FL
416 PM EDT SAT AUG 11 1990
 
THE NATIONAL WEATHER SERVICE IN MIAMI HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  500 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTHEAST FLORIDA
 
   ...WESTERN BROWARD COUNTY
 
 
AT 408 PM EDT RADAR INDICATED A SEVERE THUNDERSTORM IN SOUTHWESTERN
BROWARD COUNTY JUST TO THE WEST OF PEMBROKE PINES. THIS THUNDERSTORM
WILL BE MOVING NORTHEAST INTO THE COOPER CITY AND WESTON AREAS DURING
THE NEXT 45 MINUTES.
 
 
DAMAGING WIND...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
ELECTRICAL APPLIANCES. A MOBILE HOME IS NOT A SAFE REFUGE FROM A
SEVERE THUNDERSTORM...MOVE TO A MORE SUBSTANTIAL BUILDING.
 
IF THREATENING WEATHER IS SIGHTED...TAKE SHELTER...THEN ASK A LAW
ENFORCEMENT AGENCY TO RELAY YOUR SEVERE WEATHER REPORT TO THE LOCAL
NATIONAL WEATHER SERVICE OFFICE.
(ALWAYS SELECT THIS PHRASE AND THEN DELETE THIS LINE FROM WARNING.)

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 11, 3:51 PM EDT, 25 minutes before
FLZ020-020-020-112200-

SPECIAL WEATHER AND MARINE STATEMENT
NATIONAL WEATHER SERVICE WEST PALM BEACH FL
353 PM EDT SAT AUG 11 1990

RADAR SHOWED CLUSTERS OF THUNDESTORMS OVER EASTERN PALM BEACH...MARTIN
AND ST LUCIE COUNTIES.

THESE THUNDERSTORMS HAD PERSISTED FOR THE PAST COUPLE OF HOURS AND NOW
HAD INTENSIFIED OVER THE LAKE WORTH AREA AND WEST OF PALM BEACH
GARDENS. MOVEMENT HAD BEEN SLOW AND GENERALLY TOWARD THE COAST.

THESE THUNDERSTORMS WOULD PRODUCE VERY HEAVY RAINS IN A VERY SHORT
TIME CAUSING FLOODING IN LOW PLACES AND ON SOME ROADWAYS.
FREQUENT LIGHTNING STRIKES WERE LIKELY. THUNDERSTORMS MAY DEVELOP OVER
AREAS OF PALM BEACH...MARTIN AND ST LUCIE COUNTIES THAT HAVE NOT HAD
RAIN YET THIS AFTERNOON.

RESIDENTS AND BOATERS SHOULD BE ALERT FOR THESE STRONG THUNDERSTORMS.

NNNN
Special weather statement, Aug 11, 3:57 PM EDT, 19 minutes before
FLZ020-020-020-112200-

SPECIAL WEATHER AND MARINE STATEMENT
NATIONAL WEATHER SERVICE WEST PALM BEACH FL
353 PM EDT SAT AUG 11 1990

RADAR SHOWED CLUSTERS OF THUNDESTORMS OVER EASTERN PALM BEACH...MARTIN
AND ST LUCIE COUNTIES.

THESE THUNDERSTORMS HAD PERSISTED FOR THE PAST COUPLE OF HOURS AND NOW
HAD INTENSIFIED OVER THE LAKE WORTH AREA AND WEST OF PALM BEACH
GARDENS. MOVEMENT HAD BEEN SLOW AND GENERALLY TOWARD THE COAST.

THESE THUNDERSTORMS WOULD PRODUCE VERY HEAVY RAINS IN A VERY SHORT
TIME CAUSING FLOODING IN LOW PLACES AND ON SOME ROADWAYS.
FREQUENT LIGHTNING STRIKES WERE LIKELY. THUNDERSTORMS MAY DEVELOP OVER
AREAS OF PALM BEACH...MARTIN AND ST LUCIE COUNTIES THAT HAVE NOT HAD
RAIN YET THIS AFTERNOON.

RESIDENTS AND BOATERS SHOULD BE ALERT FOR THESE STRONG THUNDERSTORMS.

NNNN
Special weather statement, Aug 11, 4:03 PM EDT, 13 minutes before
FLZ022-112100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MIAMI FL
358 PM EDT SAT AUG 11 1990

...THUNDERSTORMS INTENSIFYING IN BROWARD AND DADE COUNTIES...

AT 350 PM EDT SATELLITE AND RADAR SHOWED THAT THUNDERSTORMS WERE
BEGINNING TO DEVELOP RAPIDLY IN DADE AND BROWARD COUNTIES. THE
STORMS EXTENDED FROM NEAR HOMESTEAD NORTHWARD TO NEAR MIAMI LAKES AND
ACROSS BROWARD COUNTY TO NEAR TAMARAC. THESE THUNDERSTORMS ARE MOVING
SLOWLY NORTHEASTWARD TOWARD THE COAST.

THE STORMS WILL CONTINUE TO PRODUCE FREQUENT LIGHTNING...STRONG GUSTY
WINDS AND POSSIBLY SOME SMALL HAIL UNTIL ABOUT 500 PM.  PERSONS
ENGAGED IN ANY OUTSIDE ACTIVITY SHOULD SEEK PROTECTION INSIDE UNTIL
THE THREAT FROM THESE STORMS HAS ENDED.

Nearby

Severe Thunderstorm Warnings in Florida, 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.