Alert archive / Florida / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 113, NWS Melbourne, FL

August 1, 1999Osceola County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Aug 1, 1999, 6:03 PM EDT for Osceola County, Florida. It was in force for 32 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Aug 1, 1999, 6:03 PM EDT (22:03 UTC)
Expired
Aug 1, 1999, 6:35 PM EDT
In force
32 min
Issued by
NWS Melbourne, FL
Area
Whole counties

County Osceola County, FL

What was reported inside it

TimeReportWhereRemark
Aug 1, 6:10 PM EDTThunderstorm Wind 50Kissimmee, FLThunderstorm winds damaged roofs and blew trees down on buildings in Kissimmee.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 12:00Z, 10.1 hours before the alert went out and 129 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 1999-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2171 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 1999-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -4 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
2171 J/kg
Mixed-layer CIN
-39 J/kg
Mixed-layer LCL
910 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
-4 m²/s²
0-3 km storm-relative helicity
46 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 KMLB 012203 RRA
SVRMLB
FLC097-012235-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MELBOURNE FL
603 PM EDT SUN AUG 1 1999

THE NATIONAL WEATHER SERVICE IN MELBOURNE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
     WESTERN OSCEOLA COUNTY IN EAST CENTRAL FLORIDA

* UNTIL 635 PM EDT

* AT 604 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM KISSIMMEE.  MOVEMENT WAS WEST AT 5 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
    WILL MOVE THROUGH KISSIMMEE BY 630 PM.


SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 58
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING AND VERY HEAVY RAIN.
MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A STRONG BUILDING.

$$

WIMMER

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Melbourne, FL wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 1, 3:30 PM EDT, 2 hours 33 minutes earlier.

Area forecast discussion, Aug 1, 3:30 PM EDT, 2 hours 33 minutes before
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
330 PM EDT SUN AUG 1 1999

CURRENTLY...HIGH AND DRY OVER MOST OF CWA...KMLB AND KDAB RECORD HI
TEMPS TEETERING ON THE BRINK OF EXTINCTION.  SCT RW/TRW FORMING
ALONG A THETA-E RIDGE NORTH OF THE CAPE AND OVER NRN PEN.  WRLY
FLOW...STRONGER THAN EXPECTED...IS SUPPRESSING ECSB FORMATION AND
APPEARS UNLIKELY N OF THE CAPE ATTM.

TONIGHT...SIMILAR PATTERN AS THE PAST FEW DAYS.  DIURNAL CONVECTION
WILL DIE OFF AFTER SUNSET. SFC TROF OVER ERN SEABOARD WILL COMBINE
WITH THE SUBTROPICAL RIDGE OVER SRN PEN TO KEEP LIGHT WRLY FLOW AND
HIGH DEWPOINTS IN PLACE.  EXPECT OVERNIGHT TEMPS TO CONTINUE IN THE
MID 70S.

MON/MON NIGHT...SOME INDICATION OF A BREAK IN THE PATTERN AS A LARGE
BUBBLE OF COOLER AIR DIVES OUT OF CANADA AND INTO THE MIDWEST.  THE
CANADIAN HI WILL MOVE ACROSS THE MIDWEST...WHILE THE ATLC HI PRES
DRIFTS SLIGHTLY TO THE N.  THE TWO WILL SQUEEZE AND AMPLIFY THE
WEAK SFC TROF OVER THE E COAST.  AXIS OF THE TROUGH WILL EXTEND
ACROSS FL PANHANDLE AND NRN PENINSULA...COULD BE A GOOD FOCUS FOR
RW/TRW DEVELOPMENT.  OTHER SIDE OF THIS COIN...HOWEVER...IS THAT THE
WRLY LOW LEVEL FLOW WILL LIKELY INCREASE OVER PEN AND SUPPRESS
ECSB.  FCST WILL INDICATE SLOWLY INCREASING POPS...BUT TOO SOON TO
GO GUNG-HO ATTM.

TUE...UPPER HIGH HAS RETROGRADED WWD AND ALLOWED WEAK UPPER TROFFING
ALONG E COAST. SFC WAVE DEVELOPMENT INDICATED BY MODELS BY TUE MORN
OFF E COAST. A LITTLE COOLING OCCURS ALOFT...BUT STILL FAIRLY WARM.
INCREASE IN PWATS OCCURING AND SHOULD HAVE SCT AFTN ACTIVITY DEVELOP
ALONG SEA BREEZE BOUNDARIES AND WILL INCREASE POPS SLIGHTLY OVER MON.
INCREASING MOISTURE AND DECREASING HEIGHTS SHOULD HELP MAX TEMPS
FROM CLIMBING QUITE AS HIGH.

WED...SFC BOUNDARY WILL PERSIST OVER NC PART OF STATE BUT AM THINKING
AVN IS TOO AGRESSIVE WITH DEPICTION OF SFC LOW AND VORT MAX OVER NRN
PART OF STATE ON WED MORN. COVERAGE OF POPS SHOULD BE A LITTLE
HIGHER WITH BETTER MOISTURE...BOUNDARY TO N AND RIDGE AXIS TO S WITH
GENERAL STORM MOTION TOWARD E COAST.

THU AND FRI...LOW LEVEL RIDGE AXIS WILL CONTINUE S OF AREA AND WEAK
SFC TROF STILL INDICATED TO N. SHOULD CONTINUE TO SEE SCT COVERAGE
AFTN TSTMS AND MAXES IN LOW/MID 90S.

MARINE...GENERALLY A WLY WIND COMPONENT THROUGH PERIOD AS SFC
BOUNDARY DRIFTS INTO NRN PART OF STATE AND WILL NEED TO WATCH HOW
SFC LOW DEVELOPMENT PLAYS OUT. GRADUAL INCREASE IN STORM COVERAGE
INTO MID WEEK.

PRELIMINARY NUMBERS
DAB GB 078/096 076/093 075 52132
MCO GB 077/097 076/094 074 52132
MLB BB 078/095 077/093 075 52131

.MLB...FIRE WEATHER WATCH 2 PM TO SUNSET FOR ALL OF ZONES 11
16...AND INTERIOR ZONES 12 17.

BRAGAW/GLITTO

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 1, 4:25 PM EDTSevere Thunderstorm WarningMLBLake45 min
Aug 1, 5:16 PM EDTSevere Thunderstorm WarningMLBOrange, Osceola49 min

Nearby

Severe Thunderstorm Warnings in Florida, 1999Every severe thunderstorm warning 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.