Alert archive / Florida / Special Marine Warnings in 2012

Special Marine Warning 310, NWS Key West, FL

August 24, 2012

NWS Key West, FL issued this special marine warning at Aug 24, 2012, 8:47 PM EDT. It was in force for 43 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 24, 2012, 8:47 PM EDT (00:47 UTC)
Expired
Aug 24, 2012, 9:30 PM EDT
In force
43 min
Issued by
NWS Key West, FL
Area
Storm-based polygon

The radar

The Key West radar (KBYX), 133 km from the middle of the area, began a volume at 00:46 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, 0.8 hours before the alert went out and 129 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.

515 
WHUS52 KKEY 250047
SMWKEY
GMZ074-075-250130-
/O.NEW.KKEY.MA.W.0310.120825T0047Z-120825T0130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SPECIAL MARINE WARNING
NATIONAL WEATHER SERVICE KEY WEST FL
847 PM EDT FRI AUG 24 2012

THE NATIONAL WEATHER SERVICE IN KEY WEST HAS ISSUED A

* SPECIAL MARINE WARNING FOR...
  STRAITS OF FLORIDA FROM WEST END OF SEVEN MILE BRIDGE TO 20 NM
  WEST OF DRY TORTUGAS 20 TO 60 NM OUT...

* UNTIL 930 PM EDT

* AT 840 PM EDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
  LINE OF THUNDERSTORMS...PRODUCING STRONG WINDS OVER 35 KNOTS FROM
  20 NAUTICAL MILES SOUTH OF COSGROVE SHOAL LIGHT TO 38 NAUTICAL
  MILES SOUTH OF TWENTY-EIGHT FOOT SHOAL LIGHT...MOVING SOUTHWEST AT
  35 KNOTS.

PREPARE FOR WIND GUSTS IN EXCESS OF 35 KNOTS...STEEP AND
FAST-BUILDING SEAS...FREQUENT LIGHTNING STRIKES...AND BLINDING
DOWNPOURS. STAY LOW OR GO BELOW...AND MAKE SURE ALL ON BOARD ARE
WEARING LIFE JACKETS.

LAT...LON 2358 8255 2358 8263 2358 8264 2361 8292
      2394 8292 2419 8220 2375 8226 2357 8247
      2357 8254
TIME...MOT...LOC 0046Z 043DEG 33KT 2410 8228 2376 8239

$$

MSB
1 follow-up statement
100 
FZUS72 KKEY 250112
MWSKEY

MARINE WEATHER STATEMENT
NATIONAL WEATHER SERVICE KEY WEST FL
912 PM EDT FRI AUG 24 2012

GMZ074-075-250130-
/O.CON.KKEY.MA.W.0310.000000T0000Z-120825T0130Z/
912 PM EDT FRI AUG 24 2012

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 930 PM EDT...

FOR THE FOLLOWING AREAS...
STRAITS OF FLORIDA FROM WEST END OF SEVEN MILE BRIDGE TO 20 NM
WEST OF DRY TORTUGAS 20 TO 60 NM OUT...

AT 910 PM EDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
LINE OF THUNDERSTORMS...PRODUCING STRONG WINDS OVER 35 KNOTS FROM 30
NAUTICAL MILES SOUTH OF TWENTY-EIGHT FOOT SHOAL LIGHT TO 50 NAUTICAL
MILES SOUTH OF TWENTY-EIGHT FOOT SHOAL LIGHT...MOVING SOUTHWEST AT 35
KNOTS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PREPARE FOR WIND GUSTS IN EXCESS OF 35 KNOTS...STEEP AND
FAST-BUILDING SEAS...AND BLINDING DOWNPOURS. MAKE SURE ALL ON BOARD
ARE WEARING LIFE JACKETS.

&&

LAT...LON 2361 8291 2394 8292 2414 8236 2364 8239
      2357 8247
TIME...MOT...LOC 0111Z 043DEG 33KT 2393 8245 2359 8256

$$

MSB

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, 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
Aug 25, 7:22 AM EDTSevere Thunderstorm WarningKEYMonroe38 min

Nearby

Special Marine Warnings in Florida, 2012Every special marine 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.