Alert archive / Florida / Tornado Watches in 1997

Tornado Watch 158

April 12, 19974 counties in Florida

The Storm Prediction Center issued this tornado watch at Apr 12, 1997, 7:00 AM EDT for 4 counties in Florida. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Apr 12, 1997, 7:00 AM EDT (11:00 UTC)
Expired
Apr 12, 1997, 1:00 PM EDT
In force
6 hr
Issued by
the Storm Prediction Center

Counties Broward County, FL, Collier County, FL, Miami-Dade County, FL, Monroe County, FL

The radar

The Miami radar (KAMX), 36 km from the middle of the area, began a volume at 11:00 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Warnings issued inside it

3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 12, 7:53 AM EDTSevere Thunderstorm WarningMFLMiami-Dade67 min
Apr 12, 8:20 AM EDTFlash Flood WarningMFLCollier115 min
Apr 12, 10:40 AM EDTFlash Flood WarningMFLCollier110 min

The nearest sounding before it

Miami, FL (KMFL), launched 00:00Z, 11.0 hours before the alert went out and 26 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 00:00Z on 1997-04-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 218 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 00:00Z on 1997-04-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 52 square meters per square second.193958Sfc1 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
218 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
956 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
52 m²/s²
0-3 km storm-relative helicity
109 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

955 
WWUS9 KMKC 121044
SEL8  
MKC WW 121044
FLZ000-121700-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 158
STORM PREDICTION CENTER NORMAN OK
644 AM EDT SAT APR 12 1997

A...THE STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR

   PARTS OF SOUTH FLORIDA                            
   AND ADJACENT COASTAL WATERS

EFFECTIVE THIS SATURDAY MORNING AND AFTERNOON UNTIL NOON EDT.

TORNADOES...LARGE HAIL...DANGEROUS LIGHTNING AND DAMAGING
THUNDERSTORM WINDS ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 70 STATUTE MILES EAST AND WEST
OF A LINE FROM 70 MILES NORTHWEST OF MIAMI FLORIDA TO 55 MILES
SOUTH OF MIAMI FLORIDA.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. 
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.
$$

C...TORNADOES AND A FEW SVR TSTMS WITH HAIL SFC AND ALF TO  3/4
INCHES.  EXTRM TURBC AND SFC WIND GUSTS TO 60 KNOTS.  A FEW CBS
WITH MAX TOPS TO 480.  MEAN WIND VECTOR 23025.

D...CHANCE FOR ISOLD TORNADOES THIS MRNG ACRS S FL...WHERE MDT VERT
SHEAR WL BE PRESENT INVOF OF WK WRM FNT AND DWPTS HAVE RISEN TO AOA
70F.  

...CORFIDI

Nearby

Tornado Watches in Florida, 1997Every tornado watch 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; radar from the NEXRAD Level II archive.