Alert archive / Florida / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 70, NWS Melbourne, FL

May 19, 1999Volusia County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at May 19, 1999, 5:42 PM EDT for Volusia County, Florida. It was in force for 48 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
May 19, 1999, 5:42 PM EDT (21:42 UTC)
Expired
May 19, 1999, 6:30 PM EDT
In force
48 min
Issued by
NWS Melbourne, FL
Area
Whole counties

County Volusia County, FL

The radar

The Melbourne radar (KMLB), 116 km from the middle of the area, began a volume at 21:42 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
May 19, 6:12 PM EDTThunderstorm Wind 50New Smyrna Beach, FLPower lines were blown down west of New Smyrna Beach.

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

Cape Canaveral, FL (KXMR), launched 12:00Z, 9.7 hours before the alert went out and 91 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, Cape Canaveral, FL at 12:00Z on 1999-05-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 372 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, Cape Canaveral, FL at 12:00Z on 1999-05-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 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
372 J/kg
Mixed-layer CIN
-143 J/kg
Mixed-layer LCL
1258 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
20 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 192142 RRA
SVRMLB
FLC127-192230-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MELBOURNE FL
542 PM EDT WED MAY 19 1999

THE NATIONAL WEATHER SERVICE IN MELBOURNE HAS ISSUED A

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

* UNTIL 630 PM EDT

* AT 542 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 8 MILES SOUTHWEST OF DAYTONA BEACH AND ALONG
  INTERSTATE 4.  MOVEMENT WAS SOUTHEAST AT 15 MPH.

* THE SEVERE THUNDERSTORM WILL CROSS...
    HIGHWAY 44 IN THE NEXT 10 MINUTES THEN MOVE JUST EAST OF LAKE
    HELEN.


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 May 19, 2:18 PM EDT, 3 hours 24 minutes earlier.

Area forecast discussion, May 19, 2:18 PM EDT, 3 hours 24 minutes before
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
218 PM EDT WED MAY 19 1999

TONIGHT...UPPER LEVEL SHORT WAVE/VORT MAX AND CONVERGENCE ZONE
AHEAD OF FRONT WILL MOVE SLOWLY SOUTHEAST AND KEEP THUNDERSTORMS
GOING THROUGH EARLY EVENING OVER FA. THE THUNDERSTORMS WILL
GENERALLY DEVELOP IN PROX TO SEA BREEZE COLLISION AND SHRT WV AXIS
IN THE N AND SHIFT SE TO COASTAL RGNS THIS EVE. THE HIGHEST POPS
TONIGHT WILL BE OVER THE S PTN OF FA DUE TO AFTERNOON INTERIOR
STORMS MOVING SOUTHEAST TOWARDS THE EAST COAST. THE COLD FRONT WILL
BECOME DIFFUSE OVERNIGHT AS RIDGE OF HIGH BUILD IN FROM THE NORTH.
PATCHY FOG SHOULD DEVELOP OVER FA EARLY THURSDAY MORNING DUE TO
LIGHT WINDS AND DECENT LOW LEVEL MOISTURE.

LONG TERM...SFC BNDRY WILL WASH OUT ACROSS NORTHERN PARTS OF FA AS
MID LVL SHRT WV/VRT AXIS MOVES SOUTH OF THE PENINSULA BY THU
MORNING. WATER VAPOR IMG SHOWS SIGNIFICANT DRYING IN THE MID LEVELS
BEHIND FEATURE BUT THE LOW LEVELS WL HAVE MINIMAL DRYING. MDL
GUIDANCE SHOWS PW VALUES FM A HIGH NEAR 1.4 THIS EVE TO JUST ABV 1.0
THU MORNING. MORE IMPORTANTLY HOWEVER...THERE SHUD BE SIGNIFICANT
SYNOPTIC DVM AS THE MDLS DIFFERENTIAL VORT ADV SHOWS BEHIND MID
LEVEL WV.

AS SFC RIDGE TENDS TO BRIDGE WHAT IS LEFT OF LOW LEVEL BNDRY AN
INVERTED TROF IS DEPICTED ESP IN ETA S OF THE HIGH. THIS IN PART MAY
BE THE REASON FOR HIER THAN EXPECTED POPS FOR TMRW. WILL BIAS POPS
HIGHEST IN THE S AS THEY SHUD HOLD ON TO THE MOISTURE THE LONGEST.

SFC RIDGE BUILDING ACROSS THE CAROLINAS WILL KEEP DEEP EASTERLY FLOW
ACROSS THE STATE INTO THE WEEKEND. GUIDANCE SHOWS LRG SCALE
SUBSIDENCE S OF RIDGE AXIS AND DRY AIR. REGARDLESS ESTRLIES WL PUSH
E COAST BREEZE RAPIDLY THRU FA DURING THE LT MORNING AND EARLY AFTN
LIMITING PCPN CHCS THRU THE WEEKEND. NOCTURNAL SHRA CHC WILL BE
LIMITED INITIALY FOR ABV MENTIONED SUBSIDENCE.

MARINE...SHRA/TS  ACTVTY WL MOVE OFF THE COAST THIS EVE AND INTO THE
OPEN WATERS. VRBL FLOW TO BECOME NE AND INC LATE THU AS RIDGE
SHIFTS S.

PRELIM...

DAB BU 064/083 065/083 068 0532-
MCO BU 065/086 066/087 067 0532-
MLB BB 067/084 068/084 069 05331

.MLB...NONE.

BORZILLERI/BLOTTMAN

In the hours before

Special weather statement, May 19, 11:45 AM EDT, 5 hours 57 minutes before
AMZ550-555-570-575-FLZ041-044>047-053-054-058-059-064-192200-

EAST CENTRAL FLORIDA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MELBOURNE FL
1145 AM EDT WED MAY 19 1999

...SCATTERED AFTERNOON AND EVENING THUNDERSTORMS...SOME STRONG...
...GREATER THAN NORMAL THREAT FOR RIP CURRENTS...

THE ATMOSPHERE WILL BECOME MODERATELY UNSTABLE THIS AFTERNOON AHEAD
OF AN APPROACHING COOL FRONT. WEAK SURFACE WINDS WILL ALLOW THE EAST
COAST SEA BREEZE TO DEVELOP EARLY IN THE AFTERNOON AND PUSH QUICKLY
INLAND. THE STRONGEST THUNDERSTORMS ARE EXPECTED TO DEVELOP DURING
THE MID AFTERNOON NORTH OF A LINE FROM CAPE CANAVERAL TO ORLANDO AND
CLERMONT. OTHER ISOLATED THUNDERSTORMS MAY DEVELOP ALONG THE SEA
BREEZE BOUNDARY SOUTH OF THE ORLANDO METRO AREA AND NEAR THE LARGER
LAKES. STORMS WILL MOVE EAST TO SOUTHEAST AT 10 TO 15 MPH AND AFFECT
SOME COASTAL COMMUNITIES LATE THIS AFTERNOON AND THIS EVENING.

SMALL HAIL...GUSTY WINDS...FREQUENT CLOUD TO GROUND LIGHTNING AND
HEAVY RAIN ARE POSSIBLE IN THE STRONGER STORMS. MOVE INDOORS AT THE
FIRST SIGN OF THREATENING SKIES.

A PERSISTENT LONG PERIOD SWELL WILL RESULT IN A GREATER THAN NORMAL
THREAT FOR RIP CURRENTS ALONG THE BEACHES OF VOLUSIA...BREVARD...
INDIAN RIVER...ST LUCIE AND MARTIN COUNTIES. THE THREAT WILL BE
GREATEST DURING THE OUTGOING TIDE THIS AFTERNOON...SO SWIM NEAR A
LIFEGUARD. NEVER ATTEMPT TO SWIM DIRECTLY AGAINST A CURRENT...BUT
MOVE AT AN ANGLE TO IT...THEN BACK TO SHORE.

BORZILLERI
Special weather statement, May 19, 11:45 AM EDT, 5 hours 57 minutes before
AMZ550-555-570-575-FLZ041-044>047-053-054-058-059-064-192200-

EAST CENTRAL FLORIDA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MELBOURNE FL
1145 AM EDT WED MAY 19 1999

...SCATTERED AFTERNOON AND EVENING THUNDERSTORMS...SOME STRONG...
...GREATER THAN NORMAL THREAT FOR RIP CURRENTS...

THE ATMOSPHERE WILL BECOME MODERATELY UNSTABLE THIS AFTERNOON AHEAD
OF AN APPROACHING COOL FRONT. WEAK SURFACE WINDS WILL ALLOW THE EAST
COAST SEA BREEZE TO DEVELOP EARLY IN THE AFTERNOON AND PUSH QUICKLY
INLAND. THE STRONGEST THUNDERSTORMS ARE EXPECTED TO DEVELOP DURING
THE MID AFTERNOON NORTH OF A LINE FROM CAPE CANAVERAL TO ORLANDO AND
CLERMONT. OTHER ISOLATED THUNDERSTORMS MAY DEVELOP ALONG THE SEA
BREEZE BOUNDARY SOUTH OF THE ORLANDO METRO AREA AND NEAR THE LARGER
LAKES. STORMS WILL MOVE EAST TO SOUTHEAST AT 10 TO 15 MPH AND AFFECT
SOME COASTAL COMMUNITIES LATE THIS AFTERNOON AND THIS EVENING.

SMALL HAIL...GUSTY WINDS...FREQUENT CLOUD TO GROUND LIGHTNING AND
HEAVY RAIN ARE POSSIBLE IN THE STRONGER STORMS. MOVE INDOORS AT THE
FIRST SIGN OF THREATENING SKIES.

A PERSISTENT LONG PERIOD SWELL WILL RESULT IN A GREATER THAN NORMAL
THREAT FOR RIP CURRENTS ALONG THE BEACHES OF VOLUSIA...BREVARD...
INDIAN RIVER...ST LUCIE AND MARTIN COUNTIES. THE THREAT WILL BE
GREATEST DURING THE OUTGOING TIDE THIS AFTERNOON...SO SWIM NEAR A
LIFEGUARD. NEVER ATTEMPT TO SWIM DIRECTLY AGAINST A CURRENT...BUT
MOVE AT AN ANGLE TO IT...THEN BACK TO SHORE.

BORZILLERI

The office that day

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

IssuedProductOfficeCountiesLasted
May 19, 5:53 PM EDTSevere Thunderstorm WarningMLBSeminole47 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.