Alert archive / Florida / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 7, NWS Melbourne, FL

April 20, 2012Lake County, Orange County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Apr 20, 2012, 3:06 PM EDT for Lake County, Orange County, Florida. It was in force for 38 min. 3 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 20, 2012, 3:06 PM EDT (19:06 UTC)
Expired
Apr 20, 2012, 3:44 PM EDT
In force
38 min
Issued by
NWS Melbourne, FL
Area
Storm-based polygon

Counties Lake County, FL, Orange County, FL

The radar

The Melbourne radar (KMLB), 98 km from the middle of the area, began a volume at 19:05 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 20, 3:14 PM EDTHAIL 0.882 Sse Lake Louisa, FLCOOP OBSERVER REPORTED ONGOING HAIL INCREASED FROM PEA TO DIME TO NICKEL SIZE. STRONG GUSTY WINDS BUT NO DAMAGE AS YET.
Apr 20, 3:15 PM EDTHAIL 0.57 Sse Clermont, FLCOCORAHS OBSERVER REPORTED HALF INCH HAIL.
Apr 20, 3:15 PM EDTHAIL 1.52 Sse Lake Louisa, FLLAKE LOUISA STATE PARK RANGER RELAYED REPORT FROM CAMPER OF PING PONG BALL SIZED HAIL.

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

The nearest sounding before it

Cape Canaveral, FL (KXMR), launched 12:00Z, 7.1 hours before the alert went out and 101 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 2012-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 414 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 2012-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 3 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
414 J/kg
Mixed-layer CIN
-31 J/kg
Mixed-layer LCL
861 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
3 m²/s²
0-3 km storm-relative helicity
22 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.

092 
WUUS52 KMLB 201906
SVRMLB
FLC069-095-202000-
/O.NEW.KMLB.SV.W.0007.120420T1906Z-120420T2000Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MELBOURNE FL
306 PM EDT FRI APR 20 2012

THE NATIONAL WEATHER SERVICE IN MELBOURNE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN LAKE COUNTY IN FLORIDA
  WESTERN ORANGE COUNTY IN FLORIDA

* UNTIL 400 PM EDT.

* AT 305 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  LAKE LOUISA...OR 10 MILES SOUTHEAST OF GROVELAND...AND MOVING EAST
  AT 15 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE...BUT ARE NOT LIMITED 
  TO...WINDERMERE...ORLANDO AND THE ATTRACTIONS AREA. 
  

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.

&&

LAT...LON 2867 8146 2864 8146 2864 8140 2858 8130
      2835 8125 2835 8179 2836 8181 2856 8183
TIME...MOT...LOC 1904Z 267DEG 10KT 2844 8175

$$



52
2 follow-up statements
018 
WWUS52 KMLB 201930
SVSMLB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MELBOURNE FL
330 PM EDT FRI APR 20 2012

FLC069-095-202000-
/O.CON.KMLB.SV.W.0007.000000T0000Z-120420T2000Z/
ORANGE-LAKE-
330 PM EDT FRI APR 20 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 400 PM EDT 
FOR SOUTHERN LAKE AND WESTERN ORANGE COUNTIES...

AT 328 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS 
LOCATED NEAR U.S. 27 IN SOUTHERN LAKE COUNTY...MOVING EAST AT 15 MPH 
TOWARD THE ATTRACTIONS AREA NEAR ORLANDO. 

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO  
ANIMAL KINGDOM...MAGIC KINGDOM...MGM STUDIOS... HOLLYWOOD STUDIOS... 
WINDERMERE...WET N WILD WATER PARK...UNIVERSAL STUDIOS...
SEA WORLD...PLEASURE ISLAND...LAKE BUENA VISTA...EPCOT. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

HAIL UP TO THE SIZE OF NICKELS HAS BEEN REPORTED AS THE STORM MOVED 
OVER LAKE LOUISA STATE PARK IN SOUTHERN LAKE COUNTY. IF YOU ARE IN 
THE PATH OF THE STORM...TAKE IMMEDIATE ACTION TO PROTECT LIFE AND 
PROPERTY.

&&

LAT...LON 2839 8177 2854 8175 2867 8146 2864 8146
      2864 8140 2858 8130 2835 8125 2835 8179
TIME...MOT...LOC 1925Z 267DEG 10KT 2844 8168

$$


52
551 
WWUS52 KMLB 201944
SVSMLB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MELBOURNE FL
344 PM EDT FRI APR 20 2012

FLC069-095-201952-
/O.CAN.KMLB.SV.W.0007.000000T0000Z-120420T2000Z/
ORANGE-LAKE-
344 PM EDT FRI APR 20 2012

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN LAKE AND 
WESTERN ORANGE COUNTIES IS CANCELLED...

THE STORM THAT PROMPTED THE SEVERE THUNDERSTORM WARNING HAD WEAKENED 
AND WAS NO LONGER SEVERE...THUS THE WARNING HAS BEEN CANCELLED.
HOWEVER...ADDITIONAL STORMS ARE EXPECTED TO STRENGTHEN THROUGH LATE 
AFTERNOON...A FEW OF THESE COULD BECOME STRONG TO SEVERE.

LAT...LON 2839 8177 2854 8175 2867 8146 2864 8146
      2864 8140 2858 8130 2835 8125 2835 8179
TIME...MOT...LOC 1942Z 267DEG 10KT 2845 8163

$$


52

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 20, 3:56 PM EDTSpecial Weather StatementMLBLake, Orange, Osceola, Seminole64 min
Apr 20, 4:08 PM EDTSevere Thunderstorm WarningMLBIndian River67 min
Apr 20, 4:09 PM EDTSevere Thunderstorm WarningMLBOrange, Osceola66 min
Apr 20, 4:15 PM EDTSpecial Marine WarningMLB2 hr
Apr 20, 4:19 PM EDTSpecial Weather StatementMLBMartin41 min
Apr 20, 4:22 PM EDTSevere Thunderstorm WarningMLBOsceola53 min
Apr 20, 4:29 PM EDTSpecial Weather StatementMLBVolusia61 min
Apr 20, 4:35 PM EDTSevere Thunderstorm WarningMLBVolusia55 min
Apr 20, 4:43 PM EDTSevere Thunderstorm WarningMLBOkeechobee62 min
Apr 20, 5:04 PM EDTSevere Thunderstorm WarningMLBLake, Volusia56 min
Apr 20, 5:20 PM EDTSpecial Weather StatementMLBIndian River40 min
Apr 20, 5:34 PM EDTSpecial Marine WarningMLB116 min
Apr 20, 5:34 PM EDTSevere Thunderstorm WarningMLBBrevard, Osceola56 min
Apr 20, 5:39 PM EDTSevere Thunderstorm WarningMLBIndian River, Saint Lucie66 min
Apr 20, 5:59 PM EDTSpecial Marine WarningMLB2 hr
Apr 20, 6:36 PM EDTSevere Thunderstorm WarningMLBBrevard, Orange, Seminole, Volusia54 min
Apr 20, 6:49 PM EDTSpecial Weather StatementMLBMartin56 min
Apr 20, 7:37 PM EDTSpecial Weather StatementMLBBrevard53 min
Apr 20, 7:49 PM EDTSpecial Marine WarningMLB41 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.