Alert archive / Florida / Severe Thunderstorm Warnings in 2003

Severe Thunderstorm Warning 102, NWS Melbourne, FL

July 31, 2003Osceola County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Jul 31, 2003, 5:47 PM EDT for Osceola County, Florida. It was in force for 43 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 31, 2003, 5:47 PM EDT (21:47 UTC)
Expired
Jul 31, 2003, 6:30 PM EDT
In force
43 min
Issued by
NWS Melbourne, FL
Area
Counties, with a storm outline in the text

County Osceola County, FL

The radar

The Melbourne radar (KMLB), 32 km from the middle of the area, began a volume at 21:50 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Cape Canaveral, FL (KXMR), launched 12:00Z, 9.8 hours before the alert went out and 61 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 2003-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1109 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Cape Canaveral, FL at 12:00Z on 2003-07-31The 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
1109 J/kg
Mixed-layer CIN
-30 J/kg
Mixed-layer LCL
703 m above ground
0-6 km bulk shear
4 kt
0-1 km storm-relative helicity
4 m²/s²
0-3 km storm-relative helicity
6 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.

275 
WUUS52 KMLB 312147
SVRMLB
FLC097-312230-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MELBOURNE FL
544 PM EDT THU JUL 31 2003

THE NATIONAL WEATHER SERVICE IN MELBOURNE HAS ISSUED A

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

* UNTIL 630 PM EDT

* AT 535 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
SEVERE THUNDERSTORM EASTERN OSCEOLA COUNTY OR 12 MILES WEST OF LONE 
CABBAGE FISH CAMP. THIS STORM WAS DEVELOPING SOUTH DOWN TO ABOUT 
YEEHAW JUNCTION. THIS STORM PRODUCED DIME SIZE HAIL IN BITHLO 
EARLIER THIS EVENING. 

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS IN EXCESS OF 58 MILES AN
HOUR...DESTRUCTIVE HAIL...DEADLY LIGHTNING AND VERY HEAVY RAIN. IF
THE STORM APPROACHES YOU...MOVE TO AN INTERIOR ROOM ON THE LOWEST
FLOOR.

LAT...LON 2833 8091 2830 8111 2778 8107 2782 8089

$$

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 Jul 31, 2:25 PM EDT, 3 hours 22 minutes earlier.

Area forecast discussion, Jul 31, 2:25 PM EDT, 3 hours 22 minutes before
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
225 PM EDT THU JUL 31 2003

.DISCUSSION...

CURRENT/TONIGHT...AN ACTIVE LINE OF STORMS ASCD WITH THE WEST COAST
SEA BREEZE BOUNDARY CONTINUES TO MOVE EAST ACROSS THE PENINSULA.
ADDITIONAL STORMS ALONG THE EAST COAST SEA BREEZE BOUNDARY ARE
CONTINUING TO INCREASE IN COVERAGE. ANTICIPATE A MERGER OVER THE
CENTRAL PENINSULA THIS EVENING AND WILL KEEP EVENING RAIN CHANCES
FAIRLY HIGH ALONG WITH THE LIKELIHOOD OF STRONG TO SEVERE CELLS OVER
THE NEXT SEVERAL HOURS.

FRI/SAT...RIDGE AXIS QUASISTATIONARY OVER CENTRAL FLORIDA WITH A
SLOW NORTH DRIFT INDICATED THROUGH THE WEEKEND. POP FORECAST WILL
REMAIN IN THE HIGH SCATTERED RANGE WITH AVAILABLE MOISTURE AND
BOUNDARY INTERACTION CONTRIBUTING TO A GOOD COVERAGE OF AFTERNOON
THUNDERSTORMS. STRONG TO ISOLD SEVERE ACTIVITY SHOULD FOCUS IN THE
INTERIOR AND NORTH COAST IN THE LATE AFTN AS THE EAST COAST SEA BRZ
MOVES INLAND. SHOULD ALSO SEE STORMS DRIFT BACK TWD THE COAST IN THE
EVENING HOURS ESPECIALLY FROM BREVARD NORTHWARD WITH A LIGHT
WESTERLY STEERING FLOW ACROSS NRN SECTIONS. BASED ON NORTHWARD DRIFT
OF RIDGE AXIS WILL USE LOWER POPS ALONG TREASURE COAST WHERE DEEP
LAYER ONSHORE FLOW WILL REDUCE PRECIP COVERAGE.

SUN-MON...INFLUENCE OF STATIONARY LOW OVER THE GREAT LAKES WILL KEEP
RIDGE AXIS SUPPRESSED SOUTHWARD TO AROUND LAKE OKEECHOBEE EARLY NEXT
WEEK. WILL KEEP SCT RANGE POPS IN THE FORECAST WITH SLY TO SLIGHT SW
COMPONENT STEERING FLOW HIGHEST POPS USED FOR NORTH COAST AND ALL OF
INTERIOR BUT STILL REMAINING IN THE SCT CATEGORY.

EXTENDED...BY AROUND MIDWEEK AXIS OF BERMUDA HIGH SHIFTS NORTH OF
THE FORECAST AREA AND DEEP EASTERLIES RETURN TO THE AREA. EXTENDED
GUID SHOWS INFLUENCE OF TROPICAL WAVES APCHG CARIB REGION SO
FORECAST SUBJECT TO CHANGE SHOULD A WAVE APPROACH THE SOUTHERN HALF
OF STATE. CURRENT FORECAST SHOWS SCT PRECIP AND WILL LEAVE FOR NOW.

.MARINE...WITH LIGHT WIND REGIME WILL SEE SPEEDS REMAINING GENERALLY
ARND 10 KNOTS OR LESS. HIGHER WIND SPEEDS ALONG IMMEDIATE COAST
DURING AFTERNOON SEA BREEZE WITH WINDS AND SEAS HIGHER NEAR
THUNDERSTORMS MOVING OFFSHORE DURING THE LATE AFTN AND EVENING HOURS.

.PRELIMINARY POINT TEMPS/POPS...
DAB TT 072/090 073/090 073 45343
MCO TT 073/092 073/092 074 55353
MLB TT 072/090 075/089 074 55352
VRB TT 072/091 075/090 074 44342 44

.MLB WATCHES/WARNINGS/ADVISORIES...NONE.

SHORT TERM...KELLY
LONG TERM....PENDERGRAST
Hazardous weather outlook, Jul 31, 10:08 AM EDT, 7 hours 39 minutes before
AMZ550-555-570-575-FLZ041-044>047-053-054-058-059-064-141-144-147-
312000-

EAST CENTRAL FLORIDA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MELBOURNE FL
1008 AM EDT THU JUL 31 2003

.DAY ONE...THIS AFTERNOON AND EVENING:

LIGHT SOUTHWEST WINDS NEAR THE SURFACE AND DAYTIME HEATING WILL ALLOW
EAST COAST SEA BREEZE FORMATION TO BEGIN BY MIDDAY...A LITTLE EARLIER
THAN PREVIOUS DAYS. A FEW STORMS WILL FORM ON THIS BOUNDARY AS IT
DRIFTS INLAND...THEN STORM COVERAGE AND INTENSITY WILL INCREASE
DURING THE LATE AFTERNOON AND EVENING AS THE EAST AND WEST COAST SEA
BREEZE BOUNDARIES COLLIDE OVER THE INTERIOR SECTIONS. LIGHT WESTERLY
STEERING FLOW WILL TRY TO PUSH THE STORMS BACK TOWARD THE EAST COAST
THIS EVENING.

THE ATMOSPHERIC PROFILE FROM THIS MORNINGS WEATHER BALLOONS SUGGESTS
MANY STORMS WILL BE CAPABLE OF PRODUCING WIND GUSTS BETWEEN 35 AND
45 MPH. AS BOUNDARIES COLLIDE THIS AFTERNOON...A FEW STORMS WILL BE
CAPABLE OF PRODUCING WIND GUSTS UP TO 60 MPH AND COIN SIZED HAIL.

ALL STORMS WILL PRODUCE DANGEROUS CLOUD TO GROUND LIGHTNING...WHICH
MAY BECOME EXCESSIVE IN STRONGER STORMS. IF YOU HEAR THUNDER...YOU
ARE CLOSE ENOUGH TO THE STORM TO BE STRUCK BY LIGHTNING. SEEK SAFE
SHELTER IMMEDIATELY. IF NO SHELTER IS NEARBY...CROUCH IN A LOW SPOT
AWAY FROM TREES AND OTHER TALL OBJECTS. WATER CONDUCTS ELECTRICITY...
SO SWIMMERS SHOULD GET OUT OF THE WATER AND IN AN ENCLOSED BUILDING
OR CAR. PICNIC SHELTERS AND DUGOUTS MAY KEEP YOU DRY BUT THEY OFFER
NO PROTECTION FROM THE LIGHTNING DANGER.

MOTORISTS SHOULD SLOW DOWN IN HEAVY RAIN TO REDUCE THE RISK OF
HYDROPLANING. AND BOATERS SHOULD BE ALERT FOR STORMS MOVING OFFSHORE
FROM THE MAINLAND THIS AFTERNOON AND EARLY EVENING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY:
SCATTERED AFTERNOON STORMS WILL DEVELOP AGAIN FRIDAY AND MOVE BACK
TOWARD THE EAST COAST ACROSS THE NORTHERN SECTIONS. THE SURFACE RIDGE
WILL DRIFT NORTH SATURDAY...PRODUCING THE HIGHEST STORM COVERAGE OVER
NORTHERN AND INTERIOR SECTIONS. THE RIDGE AXIS WILL BEGIN TO DRIFT
BACK SOUTH BY SUNDAY...ALLOWING STORMS TO APPROACH THE EAST COAST
ACROSS THE NORTHERN SECTIONS THROUGH EARLY NEXT WEEK.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTERS ARE ASKED TO SELF ACTIVATE THIS AFTERNOON IF STRONG
STORMS DEVELOP...AND RELAY ANY REPORTS OF SIGNIFICANT WEATHER TO THE
NATIONAL WEATHER SERVICE IN MELBOURNE.

FOR A GRAPHICAL VERSION OF THIS HAZARDOUS WEATHER OUTLOOK...GO TO
WWW.WEATHER.GOV AND CLICK ON EAST CENTRAL FLORIDA.

KELLY

In the hours before

Special weather statement, Jul 31, 3:14 PM EDT, 2 hours 33 minutes before
FLZ141-147-312000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MELBOURNE FL
314 PM EDT THU JUL 31 2003

...STRONG STORM CAPABLE OF PRODUCING SMALL HAIL OVER NORTHWESTERN
BREVARD COUNTY...SOUTHEASTERN VOLUSIA COUNTY...

AT 305 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STORM CAPABLE OF PRODUCING SMALL HAIL 6 MILES WEST OF
EDGEWATER...MOVING SOUTH AT 10 MPH. THIS STORM WAS DEVELOPING
ALONG THE SEA BREEZE AND WILL CONTINUE TO DRIFT SOUTH TOWARD
MAYTOWN AND PRODUCE FREQUENT LIGHTNING AND VERY HEAVY RAIN.
Special weather statement, Jul 31, 3:20 PM EDT, 2 hours 27 minutes before
FLZ059-312000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MELBOURNE FL
320 PM EDT THU JUL 31 2003

...STRONG STORM CAPABLE OF PRODUCING WINDS UP TO 50 MPH AND SMALL
HAIL WESTERN MARTIN COUNTY...

AT 310 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STORM CAPABLE OF PRODUCING STRONG WINDS AND SMALL HAIL OVER EXTREME
NORTH CENTRAL MARTIN COUNTY...MOVING NORTH AT 20 MPH. THIS IS PART
OF A CLUSTER OF LIGHTNING STORMS FORMING ALONG THE SEA BREEZE WEST
OF I 95. THESE STORMS WILL CONTINUE TO STRENGTHEN DURING THE LATE
AFTERNOON AND SPREAD WEST OF VERO BEACH TO PALM BAY. THEY HAVE THE
POTENTIAL TO PRODUCE DAMAGING WINDS AND LARGE HAIL...BUT THE
GREATEST THREAT IN THESE STORMS WILL BE LIGHTNING.
Special weather statement, Jul 31, 3:50 PM EDT, 1 hour 57 minutes before
FLZ046-312030-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MELBOURNE FL
350 PM EDT THU JUL 31 2003

...STRONG STORM CAPABLE OF PRODUCING WINDS UP TO 50 MPH AND SMALL
HAIL SEMINOLE COUNTY...

AT 340 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STORM CAPABLE OF PRODUCING STRONG WINDS AND SMALL HAIL OVER GENEVA...
DEVELOPING TO THE SOUTHWEST INTO CENTRAL SEMINOLE COUNTY.  THIS
STORM HAS THE POTENTIAL TO PRODUCE WIND GUSTS TO NEAR 50 MPH AND
POSSIBLY SMALL HAIL. HEAVY RAINS FROM THIS STORM COULD PRODUCE
ADDITIONAL RAINFALL OF ONE TO TWO INCHES AND SOME FLOODING OF
ROADWAYS AND SMALL STREAMS.
Special weather statement, Jul 31, 4:30 PM EDT, 1 hour 17 minutes before
FLZ045-053-312115-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MELBOURNE FL
430 PM EDT THU JUL 31 2003

...STRONG STORMS EXPECTED TO DEVELOP OVER OSCEOLA AND SOUTH ORANGE
COUNTIES...

AT 420 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR DETECTED THE
EAST COAST SEA BREEZE MOVING WEST INTO CENTRAL ORANGE AND OSCEOLA
COUNTIES.  AT THE SAME TIME...A STRONG OUTFLOW BOUNDARY FROM EARLIER
THUNDERSTORMS OVER CLERMONT WAS PUSHING EAST OF SAINT CLOUD AND
NARCOOSSEE...WITH A THIRD BOUNDARY PUSHING SOUTH OUT OF SEMINOLE
COUNTY.  THESE THREE BOUNDARIES WERE CONVERGING OVER CENTRAL OSCEOLA
COUNTY IN THE VICINITY OF PINE GROVE AND ALLIGATOR LAKE...AND OVER
SOUTH CENTRAL ORANGE COUNTY IN THE VICINITY OF LAKE MARY JANE.

AS THESE BOUNDARIES MERGE THROUGH 530 PM...STRONG STORMS ARE
EXPECTED TO FORM...MANY OF WHICH WILL PRODUCE FREQUENT TO EXCESSIVE
LIGHTNING AND WIND GUSTS UP TO 50 MPH.  PEOPLE IN THIS VICINITY ARE
URGED TO SEEK SHELTER INDOORS BEFORE THE STORMS DEVELOP...AND TO
REMAIN ALERT TO RAPIDLY CHANGING WEATHER CONDITIONS.

BRAGAW
Special weather statement, Jul 31, 5:08 PM EDT, 39 minutes before
FLZ045-046-312200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MELBOURNE FL
508 PM EDT THU JUL 31 2003

...STORMS WITH EXCESSIVE LIGHTNING OVER EASTERN ORANGE COUNTY...
SOUTHERN SEMINOLE COUNTY...

AT 505 PM EDT...NATIONAL WEATHER SERVICE LIGHTNING DETECTION
EQUIPMENT INDICATED A CLUSTER OF THUNDERSTORMS WITH EXCESSIVE
LIGHTNING EXTENDING FROM WEKIVA SPRINGS TO BITHLO...DRIFTING
SOUTHEAST AT 5 TO 10 MPH.

LOCATIONS IN THE PATH OF THE LIGHTNING STORM INCLUDE UNION PARK AND
UNIVERSITY PARK.

IF YOU ARE OUTDOORS...TAKE SHELTER IN A BUILDING OR ENCLOSED
AUTOMOBILE. TREES AND OPEN SHELTERS FOUND ON A BEACH OR GOLF COURSE
OFFER NO PROTECTION.

MOST PEOPLE WHO ARE STRUCK BY LIGHTNING IN FLORIDA ARE STRUCK EITHER
PRIOR TO THE RAIN REACHING THEIR LOCATION...OR AFTER THE RAIN HAS
ENDED.

BRAGAW

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 31, 4:43 PM EDTSevere Thunderstorm WarningMLBSeminole47 min
Jul 31, 5:13 PM EDTSevere Thunderstorm WarningMLBOrange47 min

Nearby

Severe Thunderstorm Warnings in Florida, 2003Every severe thunderstorm warning in 2003

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.