Alert archive / Florida / Tornado Warnings in 1991

Tornado Warning 4, NWS Miami, FL

July 21, 1991Miami-Dade County, Florida

NWS Miami, FL issued this tornado warning at Jul 21, 1991, 3:09 PM EDT for Miami-Dade County, Florida. It was in force for 36 min.

The area

The counties it named.

The facts

Issued
Jul 21, 1991, 3:09 PM EDT (19:09 UTC)
Expired
Jul 21, 1991, 3:45 PM EDT
In force
36 min
Issued by
NWS Miami, FL
Area
Whole counties

County Miami-Dade County, FL

The nearest sounding before it

Key West, FL (KEYW), launched 12:00Z, 7.2 hours before the alert went out and 169 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 1991-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3078 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, Key West, FL at 12:00Z on 1991-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 5 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
3078 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
763 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
5 m²/s²
0-3 km storm-relative helicity
15 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 211910
TORMIA
FLC025-211945-
 
BULLETIN - EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE MIAMI FL
309 PM EDT SUN JUL 21 1991
 
THE NATIONAL WEATHER SERVICE IN MIAMI HAS ISSUED A
TORNADO WARNING EFFECTIVE UNTIL  345 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTHEAST FLORIDA
 
   ...NORTH CENTRAL DADE COUNTY
 
AND THE ADJACENT COASTAL WATERS ALONG THE SOUTHEAST FLORIDA COAST
AND THE ADJACENT COASTAL WATERS
 
AT 305 PM EDT A TORNADO WAS SIGHTED NEAR HIALEAH GARDENS...ABOUT 3
MILES WEST OF OPA LOCKA AIRPORT. THE TORNADO WAS DRIFTING TO THE WEST 
MPH.
 
IF YOU ARE IN THE PATH OF A TORNADO...THE SAFEST PLACE IS UNDER
STURDY FURNITURE IN AN INTERIOR ROOM ON THE LOWEST FLOOR. USE
PILLOWS TO COVER YOUR BODY. AVOID WINDOWS. A MOBILE HOME IS NOT A
SAFE REFUGE FROM A TORNADO. 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.

What forecasters said that day

The local office's own words before this tornado 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 21, 1:57 PM EDT, 1 hour 12 minutes before
FLZ018-212000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MIAMI FL
157 PM EDT SUN JUL 21 1991

...STRONG THUNDERSTORM OVER WESTERN COLLIER COUNTY...

AT 145 PM A STRONG THUNDERSTORM HAD DEVELOPED OVER WESTERN COLLIER COU
15 MILES EAST OF NAPLES. RADAR INDICATES THIS STORM IS MOVING WEST
AROUND 15 MPH.

DURING THE NEXT FEW HOURS
RESIDENTS OF WESTERN COLLIER COUNTY AND BOATERS OVER THE COLLIER
COUNTY COASTAL WATERS SHOULD BE ALERT AND$ SEEK SAFE SHELTER IN
THE EVENT THREATENING WEATHER APPROACHES...AS THIS THUNDERSTORM
CONTAINS DANGEROUS LIGHTNING STRIKES...STRONG GUSTY WINDS...HEAVY
DOWNPOURS AND POSSIBLE HAIL.
Special weather statement, Jul 21, 1:59 PM EDT, 1 hour 10 minutes before
FLZ018-212000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MIAMI FL
157 PM EDT SUN JUL 21 1991

...STRONG THUNDERSTORM OVER WESTERN COLLIER COUNTY...

AT 145 PM A STRONG THUNDERSTORM HAD DEVELOPED OVER WESTERN COLLIER COUNTY
ABOUT 15 MILES EAST OF NAPLES. RADAR INDICATES THIS STORM IS MOVING WEST
AROUND 15 MPH.

DURING THE NEXT FEW HOURS
RESIDENTS OF WESTERN COLLIER COUNTY AND BOATERS OVER THE COLLIER
COUNTY COASTAL WATERS SHOULD BE *ALERT AND SEEK SAFE SHELTER IN
THE EVENT THREATENING WEATHER APPROACHES...AS THIS THUNDERSTORM
CONTAINS DANGEROUS LIGHTNING STRIKES...STRONG GUSTY WINDS...HEAVY
DOWNPOURS AND POSSIBLE HAIL.
Special weather statement, Jul 21, 2:43 PM EDT, 26 minutes before
FLZ015>023-211945-
SPECIAL AND MARINE WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE MIAMI FL
245 PM EDT SUN JUL 21 1991

...STRONG THUNDERSTORMS OVER NORTHWESTERN COLLIER COUNTY...

AT 227 PM MIAMI RADAR INDICATED A CLUSTER OF STRONG THUNDERSTORMS OVER
NORTHWESTERN COLLIER COUNTY IN THE VICINITY OF NAPLES. THESE STORMS WERE
MOVING WEST AT ABOUT 15 MILES AN HOUR AND WILL MOVE TO THE COASTAL WATERS
WITHIN THE NEXT HOUR. RESIDENTS AND MARINE INTERESTS SHOULD BE ALERT FOR
STRONG GUSTY WINDS...REDUCED VISIBILITIES IN PERIODS OF HEAVY RAIN...FREQUENT
LIGHTNING STRIKES...AND ROUGH SEAS.

ELSEWHERE...SCATTERED SHOWERS AND THUNDERSTORMS...SOME WITH VERY HEAVY
RAIN...CONTINUED OVER THE PENINSULA SOUTH OF A SARASOTA/VERO BEACH LINE. THE
HEAVIEST THUNDERSTORMS WERE OVER HIGHLANDS AND MAINLAND MONROE COUNTIES.

WIDELY SCATTERED SHOWERS AND THUNDERSTORMS...A FEW WITH VERY HEAVY RAIN...WERE
OVER THE ATLANTIC FROM JUST OFFSHORE VERO BEACH TO ANDROS ISLAND.

WIDELY SCATTERED SHOWERS AND THUNDERSTORMS...ONE WITH VERY HEAVY RAIN...WERE
OVER THE GULF WELL NORTH OF THE LOWER KEYS.

MOVEMENT WAS WEST AT ABOUT 15 MILES AN HOUR

THE HIGHEST PRECIPITATION TOP WAS 53 THOUSAND FEET.*..LOCATED JUST NORTHWEST OF
NAPLES.

Nearby

Tornado Warnings in Florida, 1991Every tornado warning in 1991Tornadoes in 1991

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.