Alert archive / Florida / Tornado Watches in 1998

Tornado Watch 50

February 19, 199819 counties in Florida

The Storm Prediction Center issued this tornado watch at Feb 19, 1998, 9:00 PM EST for 19 counties in Florida. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Feb 19, 1998, 9:00 PM EST (02:00 UTC)
Expired
Feb 20, 1998, 3:00 AM EST
In force
6 hr
Issued by
the Storm Prediction Center

Counties Brevard County, FL, Charlotte County, FL, DeSoto County, FL, Glades County, FL, Hardee County, FL, Highlands County, FL, Hillsborough County, FL, Indian River County, FL, Lake County, FL, Manatee County, FL, Okeechobee County, FL, Orange County, FL, Osceola County, FL, Pasco County, FL, Pinellas County, FL, Polk County, FL, Saint Lucie County, FL, Sarasota County, FL, Seminole County, FL

The radar

The Tampa radar (KTBW), 53 km from the middle of the area, began a volume at 01:46 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

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

IssuedProductOfficeCountiesLasted
Feb 19, 9:31 PM ESTTornado WarningMLBOrange, Osceola49 min
Feb 19, 9:44 PM ESTSevere Thunderstorm WarningTBWPinellas51 min
Feb 19, 9:53 PM ESTSevere Thunderstorm WarningTBWHillsborough, Manatee47 min
Feb 19, 10:23 PM ESTSevere Thunderstorm WarningMLBOrange37 min
Feb 19, 10:37 PM ESTSevere Thunderstorm WarningMLBBrevard58 min
Feb 19, 10:48 PM ESTSevere Thunderstorm WarningTBWManatee47 min
Feb 19, 10:54 PM ESTSevere Thunderstorm WarningTBWPolk46 min
Feb 20, 12:14 AM ESTSevere Thunderstorm WarningTBWHillsborough66 min
Feb 20, 1:25 AM ESTFlash Flood WarningTBWHillsborough, Pinellas4 hr
Feb 20, 2:10 AM ESTSevere Thunderstorm WarningTBWHillsborough, Manatee30 min
Feb 20, 2:20 AM ESTTornado WarningTBWHillsborough30 min

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 00:00Z, 2.0 hours before the alert went out and 53 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 00:00Z on 1998-02-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 762 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 00:00Z on 1998-02-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 267 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
762 J/kg
Mixed-layer CIN
-24 J/kg
Mixed-layer LCL
786 m above ground
0-6 km bulk shear
78 kt
0-1 km storm-relative helicity
267 m²/s²
0-3 km storm-relative helicity
289 m²/s²
Significant tornado parameter
1.6
Supercell composite
7.5

Open this sounding in Storm Lab

The text

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

586 
WWUS9 KMKC 200133
SEL0  
MKC WW 200133
FLZ000-200800-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 50
STORM PREDICTION CENTER NORMAN OK
833 PM EST THU FEB 19 1998

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

   CENTRAL FLORIDA                            
   AND ADJACENT COASTAL WATERS

EFFECTIVE THIS THURSDAY NIGHT AND FRIDAY MORNING FROM 900 PM UNTIL
300 AM EST.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 65 STATUTE MILES EITHER SIDE OF
A LINE FROM 15 MILES WEST NORTHWEST OF SARASOTA FLORIDA TO 10 MILES
EAST NORTHEAST OF MELBOURNE 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.

OTHER WATCH INFORMATION...THIS TORNADO WATCH REPLACES TORNADO WATCH
NUMBER 48.  WATCH NUMBER 48 WILL NOT BE IN EFFECT AFTER 900 PM EST. 
CONTINUE...WW 49...

DISCUSSION...THUNDERSTORM CLUSTER APPROACHING FLORIDA WEST COAST
ALONG SURFACE BOUNDARY AND AHEAD OF UPPER SHORT WAVE. MODERATE
INSTABILITY PRESENT WITH CAPES FROM 1000 TO 1500 J/KG. 40 KT LOW
LEVEL JET...70 KT MID LEVEL FLOW AND VEERING WIND PROFILE INDICATE
THREAT OF A FEW TORNADIC SUPERCELLS.


AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. 
MEAN STORM MOTION VECTOR 23045.


...ROGASH

282,0830 290,0804 271,0800 263,0822

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 20, 3:00 AM ESTTornado WatchSPCBrevard, Charlotte, Collier, DeSoto, Glades, Hardee and 12 more4 hr

Nearby

Tornado Watches in Florida, 1998Every tornado watch in 1998

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.