Alert archive / Florida / Tornado Warnings in 1999

Tornado Warning 9, NWS Tampa Bay, FL

May 21, 1999DeSoto County, Florida

NWS Tampa Bay, FL issued this tornado warning at May 21, 1999, 5:15 PM EDT for DeSoto County, Florida. It was in force for 45 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
May 21, 1999, 5:15 PM EDT (21:15 UTC)
Expired
May 21, 1999, 6:00 PM EDT
In force
45 min
Issued by
NWS Tampa Bay, FL
Area
Whole counties

County DeSoto County, FL

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 12:00Z, 9.3 hours before the alert went out and 82 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 1999-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1033 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 1999-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 36 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
1033 J/kg
Mixed-layer CIN
-65 J/kg
Mixed-layer LCL
947 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
36 m²/s²
0-3 km storm-relative helicity
76 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 KTBW 212115 RRA
TORTBW
FLC027-212200-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
515 PM EDT FRI MAY 21 1999

THE NATIONAL WEATHER SERVICE IN RUSKIN HAS ISSUED A

* TORNADO WARNING FOR...
  DESOTO COUNTY IN SOUTH CENTRAL FLORIDA

* UNTIL 600 PM EDT

* AT 515 PM...A TORNADO WAS INDICATED BY NATIONAL WEATHER SERVICE
  DOPPLER RADAR ABOUT 4 MILES NORTHWEST OF ARCADIA. MOVEMENT
  SOUTHEAST 5 TO 10 MPH.

* SOME LOCATIONS AFFECTED...

  ARCADIA 525 PM.

THIS IS A DANGEROUS SITUATION. PERSONS IN THE PATH OF THE STORM
NEED TO TAKE COVER IN A STURDY BUILDING. MOBILE HOMES AND CARS ARE
NOT SAFE.


OGLESBY

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.

NWS Tampa Bay, FL wrote its last area forecast discussion before this tornado warning went out at May 21, 3:00 PM EDT, 2 hours 15 minutes earlier.

Area forecast discussion, May 21, 3:00 PM EDT, 2 hours 15 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY-RUSKIN FL
300 PM EDT FRI MAY 21 1999

ECSB MAKING GOOD PROGRESS INTO OUR EASTERN COUNTIES AND SETTING OFF
TSRA ACROSS POLK CO. MEANWHILE...WCSB ALSO SETTING OFF QUITE A FEW
TSRA ALONG THE WEST COAST. AS I TYPE...TSRA CONTINUES OVERHEAD AT
THE OFFICE. EXPECT SHOWERS TO CONTINUE WITH SOME SEVERE ACTIVITY
POSSIBLE AS SOON AS SEABREEZES COLLIDE.

AS JAX POINTED OUT...MOS WAS AND CONTINUES TO BE STINGY WITH POPS
ACROSS THE AREA WHICH DOESNT SEEM TO REPRESENT WHAT IS ACTUALLY
HAPPENENING. THE 50H VORT LOBE...WHICH IS RIGHT OVER US THIS
AFTERNOON...IS FORECAST TO SLIDE SOUTHWARD INTO MIA CWA BY TOMORROW.
THIS MAY DECREASE COVERAGE ACROSS THE NORTH AND CENTRAL...BUT THINK
CHANCE POPS WOULD STILL BE IN ORDER. SFC HIGH IS EXPECTED TO BE IN
THE ATLANTIC WITH A LIGHT EAST/SOUTHEAST FLOW...SO WCSB SHOULD STILL
BE AROUND TO INTERACT WITH ECSB.

STILL KEEPING ONE EYE ON CARIBBEAN DISTURBANCE...BUT EACH OF THE
LATER MODEL RUNS CONTINUE TO PUSH THE SYSTEM FARTHER EAST AND IF THE
TREND CONTINUES...WILL NOT AFFECT US.

SG/67

In the hours before

Special weather statement, May 21, 1:30 PM EDT, 3 hours 45 minutes before
FLZ039-042-043-048>052-055>057-060>062-065-220000-

WEST CENTRAL AND SOUTHWEST FLORIDA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
130 PM EDT FRI MAY 21 1999

...STRONG TO SEVERE THUNDERSTORMS POSSIBLE THIS AFTERNOON AND
EVENING...

THE PRESENCE OF AN UPPER LEVEL DISTURBANCE AND PLENTY OF LOW LEVEL
MOISTURE WILL COMBINE WITH THE EAST COAST SEA BREEZE TO PRODUCE
SCATTERD STRONG TO SEVERE THUNDERSTORMS ACROSS MUCH OF THE REGION
THROUGH THE REMAINDER OF AFTERNOON AND INTO THE EVENING TONIGHT.

EAST TO SOUTHEAST FLOW WILL BRING THE EAST COAST SEA BREEZE ACROSS
THE STATE AND WILL INTERACT WITH THE WEST COAST SEA BREEZE NEAR THE
WEST COAST. DUE TO UNUSUALLY COLD AIR ALOFT...ANY THUNDERSTORMS THAT
DEVELOP WILL HAVE THE POTENTIAL FOR LARGE HAIL AND DAMAGING
DOWNBURST WINDS OF 45 MPH OR GREATER.

THE BEST CHANCES FOR THUNDERSTORMS THIS AFTERNOON WILL BE ALONG AND
SOUTH OF A TAMPA TO LAKELAND LINE...WHERE MOISTURE AND INSTABILITY
REMAIN A BIT HIGHER. HOWEVER...OTHER THUNDERSTORMS ARE POSSIBLE ALONG
ALL COASTAL COUNTIES THROUGHOUT THE REMAINDER OF THE DAY.

ALL RESIDENTS PLANNING ANY OUTDOOR ACTIVITIES SHOULD REMAIN ALERT TO
RAPIDLY CHANGING WEATHER CONDITIONS. REMEMBER...IF YOU CAN HEAR
THUNDER...YOU ARE CLOSE ENOUGH TO THE STORM TO BE STRUCK BY LIGHTNING
...SO MOVE INDOORS IMMEDIATELY.

GARRARD
Special weather statement, May 21, 1:30 PM EDT, 3 hours 45 minutes before
FLZ039-042-043-048>052-055>057-060>062-065-220000-

WEST CENTRAL AND SOUTHWEST FLORIDA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
130 PM EDT FRI MAY 21 1999

...STRONG TO SEVERE THUNDERSTORMS POSSIBLE THIS AFTERNOON AND
EVENING...

THE PRESENCE OF AN UPPER LEVEL DISTURBANCE AND PLENTY OF LOW LEVEL
MOISTURE WILL COMBINE WITH THE EAST COAST SEA BREEZE TO PRODUCE
SCATTERD STRONG TO SEVERE THUNDERSTORMS ACROSS MUCH OF THE REGION
THROUGH THE REMAINDER OF AFTERNOON AND INTO THE EVENING TONIGHT.

EAST TO SOUTHEAST FLOW WILL BRING THE EAST COAST SEA BREEZE ACROSS
THE STATE AND WILL INTERACT WITH THE WEST COAST SEA BREEZE NEAR THE
WEST COAST. DUE TO UNUSUALLY COLD AIR ALOFT...ANY THUNDERSTORMS THAT
DEVELOP WILL HAVE THE POTENTIAL FOR LARGE HAIL AND DAMAGING
DOWNBURST WINDS OF 45 MPH OR GREATER.

THE BEST CHANCES FOR THUNDERSTORMS THIS AFTERNOON WILL BE ALONG AND
SOUTH OF A TAMPA TO LAKELAND LINE...WHERE MOISTURE AND INSTABILITY
REMAIN A BIT HIGHER. HOWEVER...OTHER THUNDERSTORMS ARE POSSIBLE ALONG
ALL COASTAL COUNTIES THROUGHOUT THE REMAINDER OF THE DAY.

ALL RESIDENTS PLANNING ANY OUTDOOR ACTIVITIES SHOULD REMAIN ALERT TO
RAPIDLY CHANGING WEATHER CONDITIONS. REMEMBER...IF YOU CAN HEAR
THUNDER...YOU ARE CLOSE ENOUGH TO THE STORM TO BE STRUCK BY LIGHTNING
...SO MOVE INDOORS IMMEDIATELY.

GARRARD

The office that day

Everything else NWS Tampa Bay, FL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 20, 8:08 PM EDTSevere Thunderstorm WarningTBWHighlands32 min
May 20, 8:29 PM EDTSevere Thunderstorm WarningTBWDeSoto31 min
May 21, 3:01 PM EDTSevere Thunderstorm WarningTBWManatee34 min
May 21, 3:30 PM EDTSevere Thunderstorm WarningTBWManatee, Sarasota35 min
May 21, 3:30 PM EDTSevere Thunderstorm WarningTBWHillsborough35 min
May 21, 4:06 PM EDTSevere Thunderstorm WarningTBWHillsborough, Manatee29 min
May 21, 4:06 PM EDTSevere Thunderstorm WarningTBWPinellas29 min
May 21, 4:28 PM EDTSevere Thunderstorm WarningTBWSarasota32 min
May 21, 4:33 PM EDTSevere Thunderstorm WarningTBWHillsborough32 min
May 21, 4:33 PM EDTSevere Thunderstorm WarningTBWLee32 min
May 21, 4:49 PM EDTSevere Thunderstorm WarningTBWCharlotte31 min
May 21, 4:58 PM EDTSevere Thunderstorm WarningTBWDeSoto47 min
May 21, 5:25 PM EDTSevere Thunderstorm WarningTBWHardee50 min
May 21, 5:33 PM EDTSevere Thunderstorm WarningTBWPolk57 min
May 21, 5:42 PM EDTSevere Thunderstorm WarningTBWPinellas33 min
May 21, 6:00 PM EDTSevere Thunderstorm WarningTBWSumter45 min

Nearby

Tornado Warnings in Florida, 1999Every tornado warning in 1999Tornadoes in 1999

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.