Alert archive / Florida / Tornado Watches in 1998

Tornado Watch 43

February 17, 199819 counties in Florida

The Storm Prediction Center issued this tornado watch at Feb 17, 1998, 3:30 AM EST for 19 counties in Florida. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued: Feb 17, 1998, 3:30 AM EST (08:30 UTC)
Expired: Feb 17, 1998, 10:00 AM EST
In force: 7 hr
Issued by: the Storm Prediction Center

Counties Brevard County, FL, Charlotte County, FL, DeSoto 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, Sarasota County, FL, Seminole County, FL, Sumter County, FL, Volusia County, FL

The radar

The Tampa radar (KTBW), 57 km from the middle of the area, began a volume at 08:17 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

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

Issued	Product	Office	Counties	Lasted
Feb 17, 3:36 AM EST	Severe Thunderstorm Warning	TBW	Pinellas	44 min
Feb 17, 3:58 AM EST	Severe Thunderstorm Warning	TBW	Hillsborough	47 min
Feb 17, 4:03 AM EST	Severe Thunderstorm Warning	TBW	Sarasota	47 min
Feb 17, 4:13 AM EST	Severe Thunderstorm Warning	MLB	Lake	42 min
Feb 17, 4:35 AM EST	Tornado Warning	TBW	Manatee	35 min
Feb 17, 4:51 AM EST	Tornado Warning	TBW	Sarasota	29 min
Feb 17, 4:59 AM EST	Tornado Warning	TBW	Hardee, Polk	46 min
Feb 17, 5:00 AM EST	Severe Thunderstorm Warning	MLB	Volusia	60 min
Feb 17, 5:04 AM EST	Tornado Warning	TBW	Manatee	36 min
Feb 17, 5:34 AM EST	Severe Thunderstorm Warning	TBW	Hardee	46 min
Feb 17, 5:35 AM EST	Severe Thunderstorm Warning	MLB	Orange	55 min
Feb 17, 5:50 AM EST	Tornado Warning	MLB	Orange	45 min
Feb 17, 6:02 AM EST	Severe Thunderstorm Warning	TBW	Highlands	48 min
Feb 17, 6:19 AM EST	Tornado Warning	MLB	Seminole	46 min
Feb 17, 6:25 AM EST	Severe Thunderstorm Warning	MLB	Osceola	60 min
Feb 17, 6:50 AM EST	Severe Thunderstorm Warning	MLB	Brevard, Indian River, Volusia	60 min
Feb 17, 6:55 AM EST	Tornado Warning	MLB	Volusia	50 min

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 00:00Z, 8.5 hours before the alert went out and 57 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1385 J/kg
Mixed-layer CIN: -11 J/kg
Mixed-layer LCL: 680 m above ground
0-6 km bulk shear: 63 kt
0-1 km storm-relative helicity: 408 m²/s²
0-3 km storm-relative helicity: 419 m²/s²
Significant tornado parameter: 3.3
Supercell composite: 13.5

Open this sounding in Storm Lab

The text

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

626 
WWUS9 KMKC 170801
SEL3  
MKC WW 170801
FLZ000-171500-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 43
STORM PREDICTION CENTER NORMAN OK
301 AM EST TUE FEB 17 1998

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

   CENTRAL FLORIDA                            
   AND ADJACENT COASTAL WATERS

EFFECTIVE THIS TUESDAY MORNING FROM 330 AM UNTIL 1000 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 60 STATUTE MILES EITHER SIDE OF
A LINE FROM 15 MILES WEST SOUTHWEST OF SARASOTA FLORIDA TO 40 MILES
NORTH 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...  CONTINUE...WW 41...WW 42...

DISCUSSION...STRONG THUNDERSTORMS OVER THE EAST CENTRAL GULF OF
MEXICO ARE EXPECTED TO MOVE NORTHEASTWARD INTO CENTRAL FLORIDA THIS
MORNING.  CONVECTION IS MOVING INTO MOIST AIR MASS WITH SURFACE DEW
POINTS NEAR 70F AND MODERATE INSTABILITY /CAPE AROUND 1500 J/KG/. 
VAD WINDS SHOW STRONG FLOW INCREASING TO 50 KT OR GREATER JUST
ABOVE THE SURFACE AND EXHIBITING SOME VEERING WITH HEIGHT.  THIS
FAVORS DEVELOPMENT OF A FEW SEVERE STORMS WITH POTENTIAL FOR
ISOLATED 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 21050.


...WEISS

280,0831 292,0805 275,0795 263,0821

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Feb 16, 7:00 PM EST	Tornado Watch	SPC	Bay, Calhoun, Escambia, Gulf, Holmes, Jackson and 4 more	6 hr
Feb 16, 11:30 PM EST	Tornado Watch	SPC	Alachua, Baker, Bradford, Citrus, Clay, Columbia and 20 more	7 hr

Nearby

Tornado Watches in Florida, 1998 Every 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.