Alert archive / Florida / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 88, NWS Melbourne, FL

August 21, 2012Okeechobee County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Aug 21, 2012, 4:24 PM EDT for Okeechobee County, Florida. It was in force for 45 min. 1 report 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: Aug 21, 2012, 4:24 PM EDT (20:24 UTC)
Expired: Aug 21, 2012, 5:09 PM EDT
In force: 45 min
Issued by: NWS Melbourne, FL
Area: Storm-based polygon

County Okeechobee County, FL

The radar

The Melbourne radar (KMLB), 91 km from the middle of the area, began a volume at 20:25 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

Time	Report	Where	Remark
Aug 21, 4:42 PM EDT	TSTM WND DMG	5 N Okeechobee, FL

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, 8.4 hours before the alert went out and 133 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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.

121 
WUUS52 KMLB 212024
SVRMLB
FLC093-212130-
/O.NEW.KMLB.SV.W.0088.120821T2024Z-120821T2130Z/

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

THE NATIONAL WEATHER SERVICE IN MELBOURNE HAS ISSUED A

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

* UNTIL 530 PM EDT.

* AT 424 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 OKEECHOBEE...AND MOVING
  NORTHEAST AT 25 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE...BUT ARE NOT LIMITED
  TO...BASINGER 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 2725 8100 2726 8101 2729 8100 2730 8102
      2733 8105 2736 8104 2738 8107 2738 8110
      2764 8097 2749 8068 2738 8068 2716 8086
TIME...MOT...LOC 2024Z 213DEG 23KT 2730 8089

$$


52

1 follow-up statement

109 
WWUS52 KMLB 212109
SVSMLB

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

FLC093-212120-
/O.CAN.KMLB.SV.W.0088.000000T0000Z-120821T2130Z/
OKEECHOBEE-
509 PM EDT TUE AUG 21 2012

...THE SEVERE THUNDERSTORM WARNING FOR OKEECHOBEE COUNTY IS
CANCELLED...

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

LAT...LON 2725 8100 2726 8101 2729 8100 2730 8102
      2733 8105 2736 8104 2738 8107 2738 8110
      2764 8097 2749 8068 2738 8068 2716 8086
TIME...MOT...LOC 2110Z 213DEG 23KT 2755 8071

$$


52

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 20, 11:28 PM EDT	Special Weather Statement	MLB	Orange	47 min
Aug 21, 1:33 PM EDT	Special Weather Statement	MLB	Lake	57 min
Aug 21, 2:39 PM EDT	Special Marine Warning	MLB		66 min
Aug 21, 2:53 PM EDT	Severe Thunderstorm Warning	MLB	Brevard	37 min
Aug 21, 3:10 PM EDT	Special Marine Warning	MLB		2 hr
Aug 21, 3:12 PM EDT	Areal Flood Advisory	MLB	Lake	93 min
Aug 21, 3:15 PM EDT	Severe Thunderstorm Warning	MLB	Brevard, Volusia	45 min
Aug 21, 3:25 PM EDT	Severe Thunderstorm Warning	MLB	Lake, Orange, Seminole, Volusia	31 min
Aug 21, 3:37 PM EDT	Special Weather Statement	MLB	Brevard, Indian River, Lake, Martin, Okeechobee, Orange and 4 more	53 min
Aug 21, 3:41 PM EDT	Special Marine Warning	MLB		94 min
Aug 21, 3:54 PM EDT	Areal Flood Advisory	MLB	Lake, Orange, Seminole, Volusia	81 min
Aug 21, 4:37 PM EDT	Special Weather Statement	MLB	Brevard, Indian River, Martin, Okeechobee, Osceola, Saint Lucie	53 min
Aug 21, 4:37 PM EDT	Severe Thunderstorm Warning	MLB	Brevard	38 min
Aug 21, 4:49 PM EDT	Severe Thunderstorm Warning	MLB	Martin, Okeechobee, Saint Lucie	34 min
Aug 21, 5:06 PM EDT	Special Marine Warning	MLB		84 min
Aug 21, 5:06 PM EDT	Severe Thunderstorm Warning	MLB	Indian River	24 min
Aug 21, 5:08 PM EDT	Special Marine Warning	MLB		82 min
Aug 21, 5:12 PM EDT	Severe Thunderstorm Warning	MLB	Brevard, Osceola	20 min

Nearby

Severe Thunderstorm Warnings in Florida, 2012 Every 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.