Alert archive / Florida / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 90, NWS Melbourne, FL

August 21, 2012Martin County, Okeechobee County, Saint Lucie County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Aug 21, 2012, 4:49 PM EDT for Martin County, Okeechobee County, Saint Lucie County, Florida. It was in force for 34 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
Aug 21, 2012, 4:49 PM EDT (20:49 UTC)
Expired
Aug 21, 2012, 5:23 PM EDT
In force
34 min
Issued by
NWS Melbourne, FL
Area
Storm-based polygon

Counties Martin County, FL, Okeechobee County, FL, Saint Lucie County, FL

The radar

The Melbourne radar (KMLB), 101 km from the middle of the area, began a volume at 20:53 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.

The nearest sounding before it

Cape Canaveral, FL (KXMR), launched 12:00Z, 8.8 hours before the alert went out and 142 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 2012-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 318 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 2012-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 36 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
318 J/kg
Mixed-layer CIN
-106 J/kg
Mixed-layer LCL
1227 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
36 m²/s²
0-3 km storm-relative helicity
44 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.

942 
WUUS52 KMLB 212049
SVRMLB
FLC085-093-111-212145-
/O.NEW.KMLB.SV.W.0090.120821T2049Z-120821T2145Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MELBOURNE FL
449 PM EDT TUE AUG 21 2012

THE NATIONAL WEATHER SERVICE IN MELBOURNE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN MARTIN COUNTY IN FLORIDA
  EASTERN OKEECHOBEE COUNTY IN FLORIDA
  ST. LUCIE COUNTY IN FLORIDA

* UNTIL 545 PM EDT.

* AT 448 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH.  THIS STORM WAS LOCATED NEAR TAYLOR CREEK...OR 7 MILES
  SOUTHEAST OF OKEECHOBEE...AND MOVING NORTH AT 25 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE...BUT ARE NOT LIMITED TO...
  FOUR SEASONS ESTATES...SAINT LUCIE VILLAGE...QUEENS COVE...LAKEWOOD
  PARK...INDRIO AND FORT DRUM

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 2709 8067 2710 8067 2716 8072 2720 8080
      2719 8083 2715 8086 2715 8088 2756 8081
      2755 8031 2751 8030 2695 8059 2695 8061
TIME...MOT...LOC 2049Z 198DEG 12KT 2716 8076

$$


52
1 follow-up statement
263 
WWUS52 KMLB 212123
SVSMLB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MELBOURNE FL
523 PM EDT TUE AUG 21 2012

FLC085-093-111-212133-
/O.CAN.KMLB.SV.W.0090.000000T0000Z-120821T2145Z/
ST. LUCIE-OKEECHOBEE-MARTIN-
523 PM EDT TUE AUG 21 2012

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN MARTIN...EASTERN
OKEECHOBEE AND ST. LUCIE COUNTIES IS CANCELLED...

THE SEVERE STORM THAT PROMPTED THE WARNING HAD WEAKENED AND EXITED
THE WARNING AREA...THUS THE WARNING HAS BEEN CANCELLED.

LAT...LON 2709 8067 2710 8067 2716 8072 2720 8080
      2719 8083 2715 8086 2715 8088 2756 8081
      2755 8031 2751 8030 2695 8059 2695 8061
TIME...MOT...LOC 2123Z 198DEG 12KT 2727 8072

$$


52

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 20, 11:28 PM EDTSpecial Weather StatementMLBOrange47 min
Aug 21, 1:33 PM EDTSpecial Weather StatementMLBLake57 min
Aug 21, 2:39 PM EDTSpecial Marine WarningMLB66 min
Aug 21, 2:53 PM EDTSevere Thunderstorm WarningMLBBrevard37 min
Aug 21, 3:10 PM EDTSpecial Marine WarningMLB2 hr
Aug 21, 3:12 PM EDTAreal Flood AdvisoryMLBLake93 min
Aug 21, 3:15 PM EDTSevere Thunderstorm WarningMLBBrevard, Volusia45 min
Aug 21, 3:25 PM EDTSevere Thunderstorm WarningMLBLake, Orange, Seminole, Volusia31 min
Aug 21, 3:37 PM EDTSpecial Weather StatementMLBBrevard, Indian River, Lake, Martin, Okeechobee, Orange and 4 more53 min
Aug 21, 3:41 PM EDTSpecial Marine WarningMLB94 min
Aug 21, 3:54 PM EDTAreal Flood AdvisoryMLBLake, Orange, Seminole, Volusia81 min
Aug 21, 4:24 PM EDTSevere Thunderstorm WarningMLBOkeechobee45 min
Aug 21, 4:37 PM EDTSpecial Weather StatementMLBBrevard, Indian River, Martin, Okeechobee, Osceola, Saint Lucie53 min
Aug 21, 4:37 PM EDTSevere Thunderstorm WarningMLBBrevard38 min
Aug 21, 5:06 PM EDTSpecial Marine WarningMLB84 min
Aug 21, 5:06 PM EDTSevere Thunderstorm WarningMLBIndian River24 min
Aug 21, 5:08 PM EDTSpecial Marine WarningMLB82 min
Aug 21, 5:12 PM EDTSevere Thunderstorm WarningMLBBrevard, Osceola20 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; radar from the NEXRAD Level II archive.