Alert archive / Florida / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 3, NWS Key West, FL

August 25, 2012Monroe County, Florida

NWS Key West, FL issued this severe thunderstorm warning at Aug 25, 2012, 7:22 AM EDT for Monroe County, Florida. It was in force for 38 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 25, 2012, 7:22 AM EDT (11:22 UTC)
Expired
Aug 25, 2012, 8:00 AM EDT
In force
38 min
Issued by
NWS Key West, FL
Area
Storm-based polygon

County Monroe County, FL

The radar

The Key West radar (KBYX), 94 km from the middle of the area, began a volume at 11:23 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

Key West, FL (KEYW), launched 00:00Z, 11.4 hours before the alert went out and 97 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, Key West, FL at 00:00Z on 2012-08-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2171 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, Key West, FL at 00:00Z on 2012-08-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -42 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
2171 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
948 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
-42 m²/s²
0-3 km storm-relative helicity
10 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.

964 
WUUS52 KKEY 251122
SVRKEY
FLC087-251200-
/O.NEW.KKEY.SV.W.0003.120825T1122Z-120825T1200Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE KEY WEST FL
722 AM EDT SAT AUG 25 2012

THE NATIONAL WEATHER SERVICE IN KEY WEST HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  LOWER KEYS IN MONROE COUNTY IN FLORIDA...
  MIDDLE KEYS IN MONROE COUNTY IN FLORIDA...
  THIS INCLUDES THE COMMUNITY OF MARATHON...
  
* UNTIL 800 AM EDT

* AT 718 AM EDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN
  EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE EXTENDING
  FROM 17 MILES EAST OF WINDLEY KEY TO 18 MILES SOUTHEAST OF LOWER   
  MATECUMBE KEY TO 21 MILES SOUTH OF LONG KEY...AND MOVING NORTHWEST 
  AT 35 MPH.

* COMMUNITIES IN THE PATH OF THE SEVERE WEATHER INCLUDE UPPER
  MATECUMBE KEY...TEATABLE KEY...CONCH KEY...GRASSY KEY...KNIGHT
  KEY...PIDGEON KEY...BOOT KEY...OHIO KEY...DUCK KEY AND BAHIA HONDA
  KEY

LAT...LON 2487 8067 2483 8077 2481 8080 2479 8088
      2476 8091 2471 8106 2469 8107 2468 8111
      2471 8114 2466 8128 2480 8086 2485 8080
      2485 8075 2488 8071 2491 8070 2489 8069
      2497 8060 2497 8057 2502 8055 2504 8049
TIME...MOT...LOC 1120Z 113DEG 29KT 2489 8036 2468 8054
          2454 8072

$$

CLR
1 follow-up statement
639 
WWUS52 KKEY 251145
SVSKEY

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE KEY WEST FL
745 AM EDT SAT AUG 25 2012

FLC087-251200-
/O.CON.KKEY.SV.W.0003.000000T0000Z-120825T1200Z/
LOWER KEYS IN MONROE FL-MIDDLE KEYS IN MONROE FL-MONROE/UPPER KEYS 
745 AM EDT SAT AUG 25 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 AM EDT 
FOR THE UPPER...MIDDLE...AND LOWER KEYS IN MONROE COUNTY...

AT 741 AM EDT...A LINE OF SEVERE THUNDERSTORMS WAS REPORTED CAPABLE 
OF PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH. THESE STORMS WERE 
MOVING NORTHWEST AT 35 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
ISLAMORADA...UPPER MATECUMBE KEY...TEATABLE KEY...LAYTON...LONG
KEY...GRASSY KEY...BOOT KEY...MARATHON AND DUCK KEY.

LAT...LON 2504 8049 2502 8055 2497 8057 2497 8060
      2489 8069 2491 8070 2488 8071 2485 8075
      2485 8080 2480 8086 2466 8128 2471 8114
      2468 8111 2469 8107 2471 8106 2476 8091
      2479 8088 2481 8080 2483 8077 2487 8067
TIME...MOT...LOC 1143Z 113DEG 29KT 2496 8055 2475 8073
          2461 8091

$$

CLR

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 24, 8:01 PM EDTSpecial Marine WarningKEY89 min
Aug 24, 8:41 PM EDTSpecial Marine WarningKEY49 min
Aug 24, 8:47 PM EDTSpecial Marine WarningKEY43 min
Aug 24, 9:01 PM EDTSpecial Marine WarningKEY59 min
Aug 24, 9:18 PM EDTSpecial Marine WarningKEY57 min
Aug 24, 9:23 PM EDTSpecial Marine WarningKEY52 min
Aug 24, 9:27 PM EDTSpecial Marine WarningKEY48 min
Aug 24, 10:00 PM EDTSpecial Marine WarningKEY60 min
Aug 24, 11:00 PM EDTSpecial Marine WarningKEY45 min
Aug 25, 12:30 AM EDTHurricane WatchKEYMonroe4 hr
Aug 25, 12:30 AM EDTTropical Storm WarningKEYMonroe59 hr
Aug 25, 4:53 AM EDTHurricane WarningKEYMonroe38 hr
Aug 25, 7:11 AM EDTSevere Thunderstorm WarningKEYMonroe34 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.