Alert archive / Florida / Tornado Watches in 1997

Tornado Watch 279

May 12, 199721 counties in Florida

The Storm Prediction Center issued this tornado watch at May 12, 1997, 3:45 PM EDT for 21 counties in Florida. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
May 12, 1997, 3:45 PM EDT (19:45 UTC)
Expired
May 12, 1997, 9:00 PM EDT
In force
5 hr
Issued by
the Storm Prediction Center
All 21 counties

Brevard County, FL, Broward County, FL, Charlotte County, FL, Collier County, FL, DeSoto County, FL, Glades County, FL, Hardee County, FL, Hendry County, FL, Highlands County, FL, Hillsborough County, FL, Indian River County, FL, Lee County, FL, Manatee County, FL, Martin County, FL, Miami-Dade County, FL, Monroe County, FL, Okeechobee County, FL, Osceola County, FL, Palm Beach County, FL, Polk County, FL, Saint Lucie County, FL

The radar

The Tampa radar (KTBW), 133 km from the middle of the area, began a volume at 19:48 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.

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 12:00Z, 7.8 hours before the alert went out and 133 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, Tampa Bay, FL at 12:00Z on 1997-05-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1120 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, Tampa Bay, FL at 12:00Z on 1997-05-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 65 square meters per square second.19395878Sfc1 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
1120 J/kg
Mixed-layer CIN
-12 J/kg
Mixed-layer LCL
609 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
65 m²/s²
0-3 km storm-relative helicity
135 m²/s²
Significant tornado parameter
0.4
Supercell composite
3.0

Open this sounding in Storm Lab

The text

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

318 
WWUS9 KMKC 121914 COR
SEL9  
MKC WW 121914 COR
FLZ000-130100-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 279
STORM PREDICTION CENTER NORMAN OK
314 PM EDT MON MAY 12 1997

THE STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

CENTRAL AND SOUTH FLORIDA
AND ADJACENT COASTAL WATERS

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 345 PM UNTIL 900
PM EDT.

TORNADOES...HAIL TO 1 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 115 STATUTE MILES NORTH AND
SOUTH OF A LINE FROM 35 MILES WEST SOUTHWEST OF FORT MEYERS FLORIDA
TO 25 MILES NORTHEAST OF WEST PALM BEACH FLORIDA.

OTHER WATCH INFORMATION...THIS TORNADO WATCH REPLACES TORNADO WATCH
NUMBER 278.  WATCH NUMBER 278 WILL NOT BE IN EFFECT AFTER 345 PM
EDT.

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.

DISCUSSION...ISOLATED SUPERCELLS CONTINUE MOVING ACROSS THE EASTERN
PORTION OF SOUTH FLORIDA. A SQUALL LINE IS APPROACHING THE WEST
COAST OF FLORIDA IN ASSOCIATION WITH AN UPPER LEVEL TROUGH. WIND
FIELDS REMAIN FAVORABLE FOR SUPERCELL TORNADOES.


AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1 INCHES.  EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. 
MEAN STORM MOTION VECTOR 25030.


...VESCIO

280,0822 283,0794 251,0794 244,0822

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 12, 12:00 PM EDTTornado WatchSPCBroward, Charlotte, Collier, Glades, Hendry, Lee and 4 more5 hr

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.