Alert archive / Florida / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 12, NWS Melbourne, FL

April 20, 2012Okeechobee County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Apr 20, 2012, 4:43 PM EDT for Okeechobee County, Florida. It was in force for 62 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
Apr 20, 2012, 4:43 PM EDT (20:43 UTC)
Expired
Apr 20, 2012, 5:45 PM EDT
In force
62 min
Issued by
NWS Melbourne, FL
Area
Storm-based polygon

County Okeechobee County, FL

The radar

The Melbourne radar (KMLB), 89 km from the middle of the area, began a volume at 20:47 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, 8.7 hours before the alert went out and 132 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.

106 
WUUS52 KMLB 202043
SVRMLB
FLC093-202145-
/O.NEW.KMLB.SV.W.0012.120420T2043Z-120420T2145Z/

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

THE NATIONAL WEATHER SERVICE IN MELBOURNE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  OKEECHOBEE COUNTY IN FLORIDA

* UNTIL 545 PM EDT.

* AT 442 PM EDT...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 8 MILES
  SOUTHWEST OF BASINGER...AND MOVING NORTHEAST AT 20 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE...BUT ARE NOT LIMITED TO...
  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 2726 8101 2729 8100 2730 8102 2733 8105
      2736 8104 2738 8107 2739 8112 2741 8114
      2745 8115 2764 8091 2764 8086 2726 8068
      2723 8099
TIME...MOT...LOC 2043Z 236DEG 19KT 2734 8113

$$


BOWEN
1 follow-up statement
204 
WWUS52 KMLB 202146
SVSMLB

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

FLC093-202156-
/O.EXP.KMLB.SV.W.0012.000000T0000Z-120420T2145Z/
OKEECHOBEE-
546 PM EDT FRI APR 20 2012

...THE SEVERE THUNDERSTORM WARNING FOR OKEECHOBEE COUNTY HAS
EXPIRED...

THE SEVERE STORM THAT PROMPTED THE WARNING HAD WEAKENED AND EXITED
THE WARNING AREA...THUS THE WARNING HAS BEEN ALLOWED TO EXPIRE.

LAT...LON 2726 8101 2729 8100 2730 8102 2733 8105
      2736 8104 2738 8107 2739 8112 2741 8114
      2745 8115 2764 8091 2764 8086 2726 8068
      2723 8099
TIME...MOT...LOC 2043Z 236DEG 19KT 2734 8113

$$


52

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 20, 3:06 PM EDTSevere Thunderstorm WarningMLBLake, Orange38 min
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, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.