Alert archive / Florida / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 84, NWS Melbourne, FL

June 4, 1999Seminole County, Volusia County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Jun 4, 1999, 3:01 PM EDT for Seminole County, Volusia County, Florida. It was in force for 44 min. 2 reports 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
Jun 4, 1999, 3:01 PM EDT (19:01 UTC)
Expired
Jun 4, 1999, 3:45 PM EDT
In force
44 min
Issued by
NWS Melbourne, FL
Area
Whole counties

Counties Seminole County, FL, Volusia County, FL

The radar

The Melbourne radar (KMLB), 101 km from the middle of the area, began a volume at 19:01 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.

What was reported inside it

TimeReportWhereRemark
Jun 4, 3:15 PM EDTThunderstorm Wind 50Osteen, FLThunderstorm winds blew down power lines and trees along Route 415 south of Osteen.
Jun 4, 3:18 PM EDTHail 0.75Sanford, FL

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

Jacksonville, FL (KJAX), launched 12:00Z, 7.0 hours before the alert went out and 186 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, Jacksonville, FL at 12:00Z on 1999-06-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 640 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, Jacksonville, FL at 12:00Z on 1999-06-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 110 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
640 J/kg
Mixed-layer CIN
-97 J/kg
Mixed-layer LCL
1110 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
110 m²/s²
0-3 km storm-relative helicity
104 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 041902
SVRMLB
FLC117-127-041945-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MELBOURNE FL
301 PM EDT FRI JUN 4 1999

THE NATIONAL WEATHER SERVICE IN MELBOURNE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
     SEMINOLE COUNTY IN EAST CENTRAL FLORIDA
     SOUTHWESTERN VOLUSIA COUNTY IN EAST CENTRAL FLORIDA

* UNTIL 345 PM EDT

* AT 303 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 5 MILES EAST OF DELTONA IN SOUTHWEST VOLUSIA
  COUNTY. MOVEMENT WAS SOUTH AT 15 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
    OSTEEN IN VOLUSIA COUNTY BY 310 PM
    OVIEDO IN SEMINOLE COUNTY BY 335 PM


OTHER THUNDERSTORMS WERE DEVELOPING NEAR GENEVA AND MAY BECOME
SEVERE.

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.

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 Jun 4, 10:25 AM EDT, 4 hours 36 minutes earlier.

Area forecast discussion, Jun 4, 10:25 AM EDT, 4 hours 36 minutes before
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
1025 AM EDT FRI JUN 4 1999

CURRENTLY...13Z SURFACE ANALYSIS SHOWS SURFACE RIDGE ACROSS CENTRAL
FLORIDA WITH WESTERLY WINDS 5 TO 10 MPH. LATEST VIS SATELLITE
IMAGERY SHOWS CU DEVELOPING ACROSS SOUTHERN AREAS... INDICATIVE OF
HIGHEST MOISTURE. 10Z CAP SOUNDING SHOWS AVAILABLE MOISTURE IS
SOMEWHAT LESS THAN PREVIOUS DAYS. IN ADDITION...12Z RUC INDICATES
NVA AT H5.

FORECAST...EXPECT EAST COAST SEA BREEZE TO FORM ALONG THE COAST BY
NOON AND MOVE INLAND DURING THE AFTERNOON HOURS...BUT MAY BE A
LITTLE DELAYED FROM YESTERDAY AS WESTERLY WINDS A LITTLE MORE
PERSISTENT THIS MORNING. EXPECT CONVECTION TO INITIATE AS SEA BREEZE
INTERACTS WITH LAKE BREEZES AND PARTICULARLY WITH THE WEST COAST
BREEZE LATER THIS EVENING. OVERALL...COVERAGE OF STORMS SHOULD BE
LESS THAN YESTERDAY. NORTHERLY STEERING FLOW WILL GUIDE ANY STORMS
SOUTHWARD AT 10 TO 15 MPH...SO DO NOT EXPECT SUCH FLOODING RAINS AS
WE SAW YESTERDAY.

WILL UPDATE NORTHERN AND CENTRAL COASTAL COUNTIES TO ADD COASTAL/
INLAND RANGE OF TEMPS. OTHERWISE FORECAST LOOKS GOOD.

MARINE...NO CHANGES OTHER THAN TO TWEAK WINDS TO THE W FLG-COF LEG.

.MLB...NONE.

KELLY/CRISTALDI

In the hours before

Special weather statement, Jun 4, 11:35 AM EDT, 3 hours 26 minutes before
AMZ550-555-570-575-FLZ041-044>047-053-054-058-059-064-042200-

EAST CENTRAL FLORIDA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MELBOURNE FL
1135 AM EDT FRI JUN 4 1999

...WIDELY SCATTERED LIGHTNING STORMS EXPECTED THIS AFTERNOON...

LIGHT WINDS WILL ALLOW THE ATLANTIC SEA BREEZE TO FORM AROUND NOON
SOUTH OF CAPE CANAVERAL...AND BY 2 PM NORTH OF CAPE CANAVERAL. AS
THE SEA BREEZE BOUNDARY MOVES INLAND...IT WILL COMBINE WITH
SUFFICIENT MOISTURE TO ACT AS A FOCUS FOR SCATTERED SHOWER AND
LIGHTNING STORM FORMATION. THROUGH MID AFTERNOON...A FEW STORMS WILL
BEGIN TO FORM OVER THE COASTAL COUNTIES...ESPECIALLY INLAND SAINT
LUCIE AND MARTIN COUNTIES...WHERE LAKE AND SEA BREEZES WILL
INTERACT. STORM DEVELOPMENT WILL SHIFT INLAND AND INCREASE IN
COVERAGE LATE THIS AFTERNOON AND EVENING OVER THE CENTRAL FLORIDA
INTERIOR. STORM MOVEMENT IS EXPECTED TO BE SOUTH AT 10 TO 15 MPH.

ISOLATED STORMS COULD BECOME STRONG AND PRODUCE SMALL HAIL AND WIND
GUSTS TO AROUND 40 MPH. DEADLY CLOUD TO GROUND LIGHTNING AND BRIEF
HEAVY RAIN WILL ALSO ACCOMPANY THE STORMS. DONT TAKE CHANCES WHEN
LIGHTNING STORMS ARE NEARBY...MOVE QUICKLY TO A SAFE LOCATION
INDOORS.

AS STORMS BEGIN TO FORM ALONG THE SEA BREEZE EARLY THIS AFTERNOON...
CLOUD TO WATER LIGHTNING MAY AFFECT A FEW AREAS ALONG THE
INTRACOASTAL WATERWAYS AND NEARSHORE ATLANTIC WATERS. THE MOST
FAVORED COASTAL AREAS FOR LIGHTNING TODAY WILL BE NEAR MERRITT ISLAND
AND SOUTH OF FORT PIERCE INLET.

KELLY
Special weather statement, Jun 4, 11:35 AM EDT, 3 hours 26 minutes before
AMZ550-555-570-575-FLZ041-044>047-053-054-058-059-064-042200-

EAST CENTRAL FLORIDA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MELBOURNE FL
1135 AM EDT FRI JUN 4 1999

...WIDELY SCATTERED LIGHTNING STORMS EXPECTED THIS AFTERNOON...

LIGHT WINDS WILL ALLOW THE ATLANTIC SEA BREEZE TO FORM AROUND NOON
SOUTH OF CAPE CANAVERAL...AND BY 2 PM NORTH OF CAPE CANAVERAL. AS
THE SEA BREEZE BOUNDARY MOVES INLAND...IT WILL COMBINE WITH
SUFFICIENT MOISTURE TO ACT AS A FOCUS FOR SCATTERED SHOWER AND
LIGHTNING STORM FORMATION. THROUGH MID AFTERNOON...A FEW STORMS WILL
BEGIN TO FORM OVER THE COASTAL COUNTIES...ESPECIALLY INLAND SAINT
LUCIE AND MARTIN COUNTIES...WHERE LAKE AND SEA BREEZES WILL
INTERACT. STORM DEVELOPMENT WILL SHIFT INLAND AND INCREASE IN
COVERAGE LATE THIS AFTERNOON AND EVENING OVER THE CENTRAL FLORIDA
INTERIOR. STORM MOVEMENT IS EXPECTED TO BE SOUTH AT 10 TO 15 MPH.

ISOLATED STORMS COULD BECOME STRONG AND PRODUCE SMALL HAIL AND WIND
GUSTS TO AROUND 40 MPH. DEADLY CLOUD TO GROUND LIGHTNING AND BRIEF
HEAVY RAIN WILL ALSO ACCOMPANY THE STORMS. DONT TAKE CHANCES WHEN
LIGHTNING STORMS ARE NEARBY...MOVE QUICKLY TO A SAFE LOCATION
INDOORS.

AS STORMS BEGIN TO FORM ALONG THE SEA BREEZE EARLY THIS AFTERNOON...
CLOUD TO WATER LIGHTNING MAY AFFECT A FEW AREAS ALONG THE
INTRACOASTAL WATERWAYS AND NEARSHORE ATLANTIC WATERS. THE MOST
FAVORED COASTAL AREAS FOR LIGHTNING TODAY WILL BE NEAR MERRITT ISLAND
AND SOUTH OF FORT PIERCE INLET.

KELLY

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 3, 8:10 PM EDTSevere Thunderstorm WarningMLBLake45 min
Jun 3, 8:54 PM EDTSevere Thunderstorm WarningMLBLake36 min
Jun 4, 3:36 PM EDTSevere Thunderstorm WarningMLBOrange44 min
Jun 4, 4:26 PM EDTSevere Thunderstorm WarningMLBOsceola44 min
Jun 4, 4:47 PM EDTSevere Thunderstorm WarningMLBLake48 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; radar from the NEXRAD Level II archive.