Alert archive / Florida / Special Marine Warnings in 2013

Special Marine Warning 310, NWS Key West, FL

August 28, 2013

NWS Key West, FL issued this special marine warning at Aug 28, 2013, 11:03 AM EDT. It was in force for 57 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 28, 2013, 11:03 AM EDT (15:03 UTC)
Expired: Aug 28, 2013, 12:00 PM EDT
In force: 57 min
Issued by: NWS Key West, FL
Area: Storm-based polygon

The radar

The Miami radar (KAMX), 129 km from the middle of the area, began a volume at 15:06 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

Miami, FL (KMFL), launched 12:00Z, 3.1 hours before the alert went out and 148 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: 398 J/kg
Mixed-layer CIN: -36 J/kg
Mixed-layer LCL: 876 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 102 m²/s²
0-3 km storm-relative helicity: 102 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.2

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

834 
WHUS52 KKEY 281503
SMWKEY
GMZ072-281600-
/O.NEW.KKEY.MA.W.0310.130828T1503Z-130828T1600Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SPECIAL MARINE WARNING
NATIONAL WEATHER SERVICE KEY WEST FL
1103 AM EDT WED AUG 28 2013

THE NATIONAL WEATHER SERVICE IN KEY WEST HAS ISSUED A

* SPECIAL MARINE WARNING FOR...
  STRAITS OF FLORIDA FROM OCEAN REEF TO CRAIG KEY 20 TO 60 NM OUT...

* UNTIL NOON EDT

* AT 1057 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF THUNDERSTORMS...PRODUCING STRONG WINDS OVER 40 KNOTS FROM
  25 NAUTICAL MILES SOUTHEAST OF THE ELBOW LIGHT TO 22 NAUTICAL MILES
  SOUTHEAST OF 409 HUMPS...WITH LITTLE MOVEMENT.

THIS LINE HAS THE POTENTIAL TO PRODUCE WATERSPOUTS. SMALL CRAFT CAN BE 
SWAMPED OR OVERTURNED BY A WATERSPOUT. STAY AWAY FROM THEM AT ALL TIMES.

LAT...LON 2402 8022 2440 8034 2502 7988 2487 7975
      2473 7970
TIME...MOT...LOC 1459Z 344DEG 10KT 2495 7985 2438 8025

$$
JOHNSON

1 follow-up statement

045 
FZUS72 KKEY 281537
MWSKEY

MARINE WEATHER STATEMENT
NATIONAL WEATHER SERVICE KEY WEST FL
1137 AM EDT WED AUG 28 2013

GMZ072-281600-
/O.CON.KKEY.MA.W.0310.000000T0000Z-130828T1600Z/
1137 AM EDT WED AUG 28 2013

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL NOON EDT...

FOR THE FOLLOWING AREA...
STRAITS OF FLORIDA FROM OCEAN REEF TO CRAIG KEY 20 TO 60 NM OUT...

AT 1132 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF THUNDERSTORMS...PRODUCING STRONG WINDS OVER 35
KNOTS FROM 29 NAUTICAL MILES SOUTHEAST OF THE ELBOW LIGHT TO 19
NAUTICAL MILES NORTH OF ELBOW CAY...MOVING LITTLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WATERSPOUT IS A TORNADO OVER WATER THAT CAN BE DANGEROUS AND EVEN
DEADLY. SMALL CRAFT CAN BE SWAMPED OR OVERTURNED BY A WATERSPOUT.
STAY AWAY FROM THEM AT ALL TIMES.

&&

LAT...LON 2402 8022 2440 8034 2502 7988 2487 7975
      2473 7970
TIME...MOT...LOC 1536Z 344DEG 10KT 2485 7982 2428 8022

$$
JOHNSON

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 27, 11:46 PM EDT	Special Marine Warning	KEY		59 min
Aug 28, 12:33 AM EDT	Special Marine Warning	KEY		57 min
Aug 28, 1:41 AM EDT	Special Marine Warning	KEY		64 min
Aug 28, 2:02 AM EDT	Areal Flood Advisory	KEY	Monroe	118 min
Aug 28, 3:07 AM EDT	Special Marine Warning	KEY		53 min
Aug 28, 3:59 AM EDT	Special Marine Warning	KEY		61 min
Aug 28, 7:15 AM EDT	Special Marine Warning	KEY		60 min
Aug 28, 8:17 AM EDT	Special Marine Warning	KEY		58 min
Aug 28, 12:14 PM EDT	Special Marine Warning	KEY		61 min

Nearby

Special Marine Warnings in Florida, 2013 Every special marine warning in 2013

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.