Alert archive / Florida / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 97, NWS Melbourne, FL

December 11, 2012Okeechobee County, Osceola County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Dec 11, 2012, 5:35 PM EST for Okeechobee County, Osceola County, Florida. It was in force for 40 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
Dec 11, 2012, 5:35 PM EST (22:35 UTC)
Expired
Dec 11, 2012, 6:15 PM EST
In force
40 min
Issued by
NWS Melbourne, FL
Area
Storm-based polygon

Counties Okeechobee County, FL, Osceola County, FL

The nearest sounding before it

Cape Canaveral, FL (KXMR), launched 12:00Z, 10.6 hours before the alert went out and 110 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 2012-12-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 75 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 2012-12-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 96 square meters per square second.19395878Sfc1 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
75 J/kg
Mixed-layer CIN
-238 J/kg
Mixed-layer LCL
1061 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
96 m²/s²
0-3 km storm-relative helicity
125 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.

722 
WUUS52 KMLB 112235
SVRMLB
FLC093-097-112315-
/O.NEW.KMLB.SV.W.0097.121211T2235Z-121211T2315Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MELBOURNE FL
535 PM EST TUE DEC 11 2012

THE NATIONAL WEATHER SERVICE IN MELBOURNE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN OKEECHOBEE COUNTY IN FLORIDA
  EXTREME SOUTHEASTERN OSCEOLA COUNTY IN FLORIDA

* UNTIL 615 PM EST.

* AT 535 PM EST...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED 6 MILES
  SOUTH OF THE KISSIMMEE PRAIRIE PRESERVE...OR 10 MILES NORTHWEST
  OF BASINGER...AND MOVING NORTHEAST AT 20 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE...BUT ARE NOT LIMITED TO...
  YEEHAW JUNCTION

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.

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

&&

LAT...LON 2741 8112 2755 8120 2759 8116 2771 8088
      2769 8087 2764 8088 2764 8084 2754 8077
TIME...MOT...LOC 2235Z 244DEG 18KT 2753 8108

$$
2 follow-up statements
484 
WWUS52 KMLB 112249
SVSMLB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MELBOURNE FL
549 PM EST TUE DEC 11 2012

FLC093-097-112315-
/O.CON.KMLB.SV.W.0097.000000T0000Z-121211T2315Z/
OSCEOLA-OKEECHOBEE-
549 PM EST TUE DEC 11 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM EST
FOR NORTHERN OKEECHOBEE AND EXTREME SOUTHEASTERN OSCEOLA COUNTIES...

AT 549 PM EST...NATIONAL WEATHER SERVICE METEOROLOGISTS CONTINUED TO
DETECT A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED NEAR KISSIMMEE PRAIRIE PRESERVE...OR 11 MILES NORTH OF 
BASINGER...MOVING EAST NORTHEAST AT 20 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO YEEHAW 
JUNCTION.

THIS STORM WILL MOVE ALONG AND JUST NORTH OF OKEECHOBEE COUNTY 
HIGHWAY 724 AND TOWARD U.S. HIGHWAY 441 AND THE FLORIDA TURNPIKE 
BETWEEN FORT DRUM AND YEEHAW JUNCTION.

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.

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...FREQUENT CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY! LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

&&

LAT...LON 2759 8114 2771 8088 2769 8087 2764 8088
      2764 8084 2754 8077 2747 8106
TIME...MOT...LOC 2247Z 244DEG 18KT 2757 8100

$$
153 
WWUS52 KMLB 112314
SVSMLB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MELBOURNE FL
614 PM EST TUE DEC 11 2012

FLC093-097-112323-
/O.EXP.KMLB.SV.W.0097.000000T0000Z-121211T2315Z/
OSCEOLA-OKEECHOBEE-
614 PM EST TUE DEC 11 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN OKEECHOBEE AND
EXTREME SOUTHEASTERN OSCEOLA COUNTIES WILL EXPIRE AT 615 PM EST...

THE SEVERE STORM THAT PROMPTED THE WARNING HAD WEAKENED AND WAS NO 
LONGER CAPABLE OF PRODUCING LARGE HAIL OR DAMAGING WIND GUSTS.
THEREFORE...THE WARNING WILL BE ALLOWED TO EXPIRE ON SCHEDULE.

THE STORM WILL PRODUCE LOCALLY HEAVY DOWNPOURS AND CLOUD TO GROUND 
LIGHTNING AS IT CROSSES HIGHWAY 441 AND THE FLORIDA TURNPIKE NEAR 
THE OKEECHOBEE OSCEOLA COUNTY LINE THROUGH 630 PM.

LAT...LON 2759 8114 2771 8088 2769 8087 2764 8088
      2764 8084 2754 8077 2747 8106
TIME...MOT...LOC 2313Z 244DEG 18KT 2764 8086

$$



CRISTALDI

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 10, 10:23 PM ESTSmall Craft AdvisoryMLB6 hr
Dec 11, 3:28 PM ESTSpecial Weather StatementMLBVolusia3 hr
Dec 11, 5:12 PM ESTSpecial Weather StatementMLBOkeechobee48 min

Nearby

Severe Thunderstorm Warnings in Florida, 2012Every severe thunderstorm warning in 2012

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.