Alert archive / Florida / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 91, NWS Melbourne, FL

August 21, 2012Indian River County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Aug 21, 2012, 5:06 PM EDT for Indian River County, Florida. It was in force for 24 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, 5:06 PM EDT (21:06 UTC)
Expired: Aug 21, 2012, 5:30 PM EDT
In force: 24 min
Issued by: NWS Melbourne, FL
Area: Storm-based polygon

County Indian River County, FL

The radar

The Melbourne radar (KMLB), 58 km from the middle of the area, began a volume at 21:07 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, 9.1 hours before the alert went out and 92 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.

449 
WUUS52 KMLB 212106
SVRMLB
FLC061-212130-
/O.NEW.KMLB.SV.W.0091.120821T2106Z-120821T2130Z/

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

THE NATIONAL WEATHER SERVICE IN MELBOURNE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN INDIAN RIVER COUNTY IN FLORIDA

* UNTIL 530 PM EDT.

* AT 502 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 SOUTH BEACH...OR NEAR 
  VERO BEACH SOUTH...AND MOVING NORTH AT 25 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE...BUT ARE NOT LIMITED TO...
  VERO BEACH...GIFFORD...INDIAN RIVER SHORES...WINTER BEACH AND   
WABASSO.

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 2755 8035 2756 8047 2782 8047 2781 8042
      2780 8041 2771 8036 2763 8034 2762 8033
      2758 8032 2756 8032
TIME...MOT...LOC 2105Z 189DEG 14KT 2762 8036

$$


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, 4:24 PM EDT	Severe Thunderstorm Warning	MLB	Okeechobee	45 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, 5:08 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.