Alert archive / Florida / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 17, NWS Melbourne, FL

April 5, 2011Lake County, Volusia County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Apr 5, 2011, 7:45 AM EDT for Lake County, Volusia County, Florida. It was in force for 60 min. 4 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Apr 5, 2011, 7:45 AM EDT (11:45 UTC)
Expired
Apr 5, 2011, 8:45 AM EDT
In force
60 min
Issued by
NWS Melbourne, FL
Area
Storm-based polygon

Counties Lake County, FL, Volusia County, FL

The radar

The Melbourne radar (KMLB), 116 km from the middle of the area, began a volume at 11:48 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
Apr 5, 8:25 AM EDTTSTM WND GST 604 Wnw Ormond Beach, FLKOMN AT ORMOND BEACH MUNICIPAL AIRPORT MEASURED A WIND GUST OF 52 KT/60 MPH.
Apr 5, 8:30 AM EDTFUNNEL CLOUDDaytona Beach Intl Spee, FLOBSERVER REPORTED A FUNNEL CLOUD OVER DAYTONA BEACH INTERNATIONAL SPEEDWAY. ALSO REPORTED ESTIMATED WIND SPEED OF 55 MPH.
Apr 5, 8:40 AM EDTTSTM WND DMGDeland, FLLARGE TREE DOWN. SPECIFIC LOCATION UNKNOWN. TIME ESTIMATED FROM RADAR. REPORT RELAYED FROM BROACAST MEDIA.
Apr 5, 8:43 AM EDTTSTM WND DMG1 W De Land, FLLARGE TREE DOWN ACROSS ROADWAY AND ON A CAR AT N BOUNDARY AND W WISCONSIN. TIME ESTIMATED FROM RADAR. REPORT RELAYED FROM BROACAST MEDIA AND LAW ENFORCEMENT.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 5, 7:04 AM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Cape Canaveral, FL (KXMR), launched 00:00Z, 11.8 hours before the alert went out and 94 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 00:00Z on 2011-04-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 731 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 00:00Z on 2011-04-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 89 square meters per square second.193958Sfc1 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
731 J/kg
Mixed-layer CIN
-46 J/kg
Mixed-layer LCL
1106 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
89 m²/s²
0-3 km storm-relative helicity
114 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

595 
WUUS52 KMLB 051145
SVRMLB
FLC069-127-051245-
/O.NEW.KMLB.SV.W.0017.110405T1145Z-110405T1245Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MELBOURNE FL
745 AM EDT TUE APR 5 2011

THE NATIONAL WEATHER SERVICE IN MELBOURNE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN LAKE COUNTY IN FLORIDA
  VOLUSIA COUNTY IN FLORIDA

* UNTIL 845 AM EDT.

* AT 741 AM EDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN
  EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE EXTENDING
  FROM 39 MILES NORTH OF ORMOND BY THE SEA TO 10 MILES NORTH OF THE
  VILLAGES...OR ALONG A LINE EXTENDING FROM 27 MILES NORTH OF
  ANDALUSIA TO 8 MILES SOUTH OF LYNNE...AND MOVING EAST AT 50 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE...BUT ARE NOT LIMITED TO...
  FRUITLAND PARK...LEESBURG...LAKE GRIFFIN...EMERALDA...LISBON...LAKE
  GEORGE...MID FLORIDA LAKES...TAVARES...EUSTIS...MOUNT DORA...
  PIERSON...PAISLEY...BARBERVILLE...CASSIA...DE LEON SPRINGS...DELEON
  SPRINGS...DE BARY...DEBARY...DE LAND...DELAND...ORANGE CITY...LAKE
  MONROE...ORMOND BEACH...LAKE HELEN...DELTONA...HOLLY HILL...DAYTONA
  BEACH INTL SPEEDWAY...DAYTONA INTERNATIONAL SPEEDWAY...OSTEEN...
  DAYTONA BEACH...OAK HILL...NEW SMYRNA BEACH...ELDORA...BETHUNE
  BEACH...WILBUR BY THE SEA...SOUTH DAYTONA...PORT ORANGE...PONCE
  INLET...EDGEWATER AND APOLLO BEACH

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS IN EXCESS OF 58 MILES AN
HOUR AND OR LARGE DESTRUCTIVE HAIL. FREQUENT TO EXCESSIVE LIGHTNING
AND VERY HEAVY RAIN WILL ALSO BE POSSIBLE. IF THE STORM APPROACHES
YOU...SEEK SHELTER IN AN ENCLOSED BUILDING ON THE LOWEST FLOOR. KEEP
AWAY FROM WINDOWS.

NATIONAL WEATHER SERVICE METEOROLOGISTS ALSO DETECTED SOME WEAK
ROTATION WITHIN THIS STORM. WHILE NOT IMMEDIATELY LIKELY...A TORNADO
MAY STILL DEVELOP. IF A TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO
A PLACE OF SAFETY IN A STURDY STRUCTURE...SUCH AS A SMALL INTERIOR
ROOM.

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR THE WARNED AREA INTO 
EARLY AFTERNOON.

&&

LAT...LON 2915 8096 2879 8072 2878 8073 2887 8080
      2885 8082 2879 8078 2884 8110 2883 8132
      2887 8136 2881 8145 2879 8195 2896 8196
      2897 8166 2933 8167 2940 8142 2927 8140
      2927 8116 2941 8116 2943 8109
TIME...MOT...LOC 1145Z 270DEG 42KT 2986 8125 2909 8191

$$
2 follow-up statements
922 
WWUS52 KMLB 051220
SVSMLB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MELBOURNE FL
820 AM EDT TUE APR 5 2011

FLC069-127-051245-
/O.CON.KMLB.SV.W.0017.000000T0000Z-110405T1245Z/
LAKE-VOLUSIA-
820 AM EDT TUE APR 5 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 845 AM EDT
FOR VOLUSIA AND NORTHERN LAKE COUNTIES...

AT 813 AM EDT...NATIONAL WEATHER SERVICE METEOROLOGISTS CONTINUED TO
DETECT A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING 
WINDS IN EXCESS OF 60 MPH. THESE STORMS WERE LOCATED ALONG A LINE 
EXTENDING FROM 38 MILES NORTH OF TOMOKA STATE PARK TO ALEXANDER 
SPRINGS...MOVING EAST AT 40 TO 50 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO 
BLUFFTON...CASSIA...FULLERVILLE...CONRAD...FOREST HILLS...PONCE DE 
LEON SPRINGS...DE LEON SPRINGS...DELEON SPRINGS...HIGH 
BANKS...GLENWOOD...FATIO...DEBARY...DELAND...ORANGE CITY...ORMOND BY 
THE SEA...ENTERPRISE...HIGHLANDS...CASSADAGA...DELTONA...HOLLY 
HILL...DAYTONA INTERNATIONAL SPEEDWAY...OSTEEN...DAYTONA BEACH...OAK 
HILL...NEW SMYRNA BEACH...HARBOR OAKS...ELDORA...TURTLE MOUND...PORT 
ORANGE...PONCE INLET...FARMTON...EDGEWATER...BLAKE...APOLLO BEACH 
AND ALLANDALE

PRECAUTIONARY/PREPAREDNESS ACTIONS...

NATIONAL WEATHER SERVICE METEOROLOGISTS ALSO DETECTED WEAK ROTATION
WITHIN THIS STORM. WHILE NOT IMMEDIATELY LIKELY...A TORNADO MAY STILL
DEVELOP. IF A TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF
SAFETY IN A STURDY STRUCTURE...SUCH AS A SMALL INTERIOR ROOM.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 200 PM EDT
TUESDAY AFTERNOON FOR EAST CENTRAL FLORIDA.

&&

LAT...LON 2915 8096 2879 8072 2878 8073 2887 8080
      2885 8082 2879 8078 2884 8110 2883 8132
      2887 8136 2881 8145 2879 8195 2896 8196
      2897 8166 2933 8167 2940 8142 2927 8140
      2927 8116 2941 8116 2943 8109
TIME...MOT...LOC 1217Z 270DEG 42KT 2986 8082 2909 8148

$$

SEDLOCK
121 
WWUS52 KMLB 051242
SVSMLB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MELBOURNE FL
842 AM EDT TUE APR 5 2011

FLC069-127-051251-
/O.EXP.KMLB.SV.W.0017.000000T0000Z-110405T1245Z/
LAKE-VOLUSIA-
842 AM EDT TUE APR 5 2011

...THE SEVERE THUNDERSTORM WARNING FOR VOLUSIA AND NORTHERN LAKE 
COUNTIES WILL BE ALLOWED TO EXPIRE AT 845 AM EDT...

THE SEVERE STORM THAT PROMPTED THE WARNING HAD WEAKENED...THUS THE 
WARNING HAS BEEN ALLOWED TO EXPIRE. STRONG WIND GUSTS OF 45 TO 55 
MPH WILL BE POSSIBLE IN STRONGER CELLS WITHIN THIS LINE THROUGH 10 
AM THIS MORNING.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 200 PM EDT
TUESDAY AFTERNOON FOR EAST CENTRAL FLORIDA.

LAT...LON 2915 8096 2879 8072 2878 8073 2887 8080
      2885 8082 2879 8078 2884 8110 2883 8132
      2887 8136 2881 8145 2879 8195 2896 8196
      2897 8166 2933 8167 2940 8142 2927 8140
      2927 8116 2941 8116 2943 8109
TIME...MOT...LOC 1241Z 270DEG 42KT 2986 8050 2909 8116

$$

SEDLOCK

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 5, 3:10 AM EDTLake Wind AdvisoryMLBLake, Okeechobee, Orange, Osceola, Seminole, Volusia10 hr
Apr 5, 7:20 AM EDTSpecial Weather StatementMLBLake, Volusia55 min
Apr 5, 7:48 AM EDTSpecial Marine WarningMLB117 min
Apr 5, 8:15 AM EDTSevere Thunderstorm WarningMLBLake, Orange, Osceola, Seminole60 min
Apr 5, 8:45 AM EDTSpecial Weather StatementMLBVolusia45 min
Apr 5, 8:52 AM EDTSevere Thunderstorm WarningMLBBrevard, Volusia38 min
Apr 5, 9:11 AM EDTSevere Thunderstorm WarningMLBBrevard, Lake, Orange, Osceola, Seminole, Volusia64 min
Apr 5, 9:19 AM EDTSpecial Marine WarningMLB116 min
Apr 5, 10:14 AM EDTSevere Thunderstorm WarningMLBBrevard, Indian River, Osceola61 min
Apr 5, 10:50 AM EDTSpecial Marine WarningMLB115 min
Apr 5, 10:58 AM EDTSevere Thunderstorm WarningMLBBrevard, Indian River, Okeechobee, Saint Lucie62 min
Apr 5, 11:59 AM EDTSevere Thunderstorm WarningMLBMartin, Okeechobee, Saint Lucie61 min
Apr 5, 12:38 PM EDTSpecial Marine WarningMLB112 min
Apr 5, 12:59 PM EDTSevere Thunderstorm WarningMLBMartin46 min

Nearby

Severe Thunderstorm Warnings in Florida, 2011Every severe thunderstorm warning in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.