Alert archive / Florida / Special Marine Warnings in 2021

Special Marine Warning 21, NWS Miami, FL

February 19, 2021

NWS Miami, FL issued this special marine warning at Feb 19, 2021, 5:53 PM EST. It was in force for 53 min. 2 reports 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: Feb 19, 2021, 5:53 PM EST (22:53 UTC)
Expired: Feb 19, 2021, 6:46 PM EST
In force: 53 min
Issued by: NWS Miami, FL
Area: Storm-based polygon
Hail: 0.0 in
Wind: 34.0 mph

The radar

The Miami radar (KAMX), 76 km from the middle of the area, began a volume at 22:55 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
Feb 19, 5:57 PM EST	MARINE TSTM WIND 41	2 Ne Dania Beach, FL	MESONET STATION XPEG AT PORT EVERGLADES REPORTED A 41 MPH/36 KT WIND GUST AT 5:57 PM.
Feb 19, 6:01 PM EST	MARINE TSTM WIND 39	3 Se Fort Lauderdale, FL	MESONET STATION AU497 AT FORT LAUDERDALE REPORTED A 39 MPH/34 KT WIND GUST AT 6:01 PM.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Miami, FL (KMFL), launched 12:00Z, 10.9 hours before the alert went out and 50 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: 562 J/kg
Mixed-layer CIN: -15 J/kg
Mixed-layer LCL: 800 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 83 m²/s²
0-3 km storm-relative helicity: 81 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.1

Open this sounding in Storm Lab

The text

As transmitted.

877 
WHUS52 KMFL 192253
SMWMFL
AMZ650-651-200000-
/O.NEW.KMFL.MA.W.0021.210219T2253Z-210220T0000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Special Marine Warning
National Weather Service Miami FL
553 PM EST Fri Feb 19 2021

The National Weather Service in Miami has issued a

* Special Marine Warning for...
  Coastal waters from Deerfield Beach to Ocean Reef FL out 20 NM...
  Coastal waters from Jupiter Inlet to Deerfield Beach FL out 20
  NM...

* Until 700 PM EST.

* At 553 PM EST, a severe thunderstorm capable of producing
  waterspouts was located over Port Everglades, or over Hollywood,
  moving northeast at 25 knots.

  HAZARD...Waterspouts and wind gusts 34 knots or greater.

  SOURCE...Radar.

  IMPACT...Waterspouts can easily overturn boats and create locally 
           hazardous seas. Small craft could be damaged in briefly 
           higher winds and suddenly higher waves.

* Locations impacted include...
  Lauderdale-By-The-Sea, Hollywood, Deerfield Beach, Port Everglades,
  Hallandale, Fort Lauderdale, Lighthouse Point, Boca Raton, Sea
  Ranch Lakes, Pompano Beach, Hillsboro Beach and Golden Beach.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor until hazardous weather passes.

Report severe weather to the Coast Guard or the National Weather
Service. You can also share your report with NWS Miami on Facebook
and Twitter.

&&

LAT...LON 2599 7980 2597 8017 2638 8014 2637 7976
TIME...MOT...LOC 2253Z 246DEG 25KT 2609 8013 

WATERSPOUT...POSSIBLE
HAIL...0.00IN
WIND...>34KTS

$$

Weinman

2 follow-up statements

307 
FZUS72 KMFL 192302
MWSMFL

Marine Weather Statement
National Weather Service Miami FL
602 PM EST Fri Feb 19 2021

AMZ650-651-200000-
/O.CON.KMFL.MA.W.0021.000000T0000Z-210220T0000Z/
602 PM EST Fri Feb 19 2021

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 700 PM EST...

For the following areas...
Coastal waters from Deerfield Beach to Ocean Reef FL out 20 NM...
Coastal waters from Jupiter Inlet to Deerfield Beach FL out 20 NM...

At 602 PM EST, a severe thunderstorm capable of producing waterspouts
was located over Fort Lauderdale, moving northeast at 25 knots.

HAZARD...Waterspouts and wind gusts to 40 knots.

SOURCE...Radar indicated.

IMPACT...Waterspouts can easily overturn boats and create locally 
         hazardous seas. Small craft could be damaged in briefly 
         higher winds and suddenly higher waves.

Locations impacted include...
Lauderdale-By-The-Sea, Hollywood, Deerfield Beach, Port Everglades,
Hallandale, Fort Lauderdale, Lighthouse Point, Boca Raton, Sea Ranch
Lakes, Pompano Beach, Hillsboro Beach and Golden Beach.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor immediately as gusty winds and high waves are
expected.

Report severe weather to the Coast Guard or the National Weather
Service. You can also share your report with NWS Miami on Facebook
and Twitter.

&&

LAT...LON 2599 7980 2597 8017 2638 8014 2637 7976
TIME...MOT...LOC 2302Z 246DEG 25KT 2612 8006 

WATERSPOUT...POSSIBLE
HAIL...0.00IN
WIND...40KTS

$$

Weinman

231 
FZUS72 KMFL 192346
MWSMFL

Marine Weather Statement
National Weather Service Miami FL
646 PM EST Fri Feb 19 2021

AMZ650-651-192355-
/O.CAN.KMFL.MA.W.0021.000000T0000Z-210220T0000Z/
646 PM EST Fri Feb 19 2021

...THE SPECIAL MARINE WARNING IS CANCELLED...

The affected areas were... 
Coastal waters from Deerfield Beach to Ocean Reef FL out 20 NM...
Coastal waters from Jupiter Inlet to Deerfield Beach FL out 20 NM...

The thunderstorm that prompted the warning has weakened. Mariners 
can still expect gusty winds to around 30 knots, locally higher 
waves, lightning strikes, and heavy downpours.

LAT...LON 2599 7980 2597 8017 2638 8014 2637 7976
TIME...MOT...LOC 2344Z 246DEG 25KT 2668 7941 

$$

RAG

The office that day

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

Issued	Product	Office	Counties	Lasted
Feb 19, 2:41 AM EST	Small Craft Advisory	MFL		4 days
Feb 19, 1:17 PM EST	Special Marine Warning	MFL		58 min
Feb 19, 2:34 PM EST	Special Weather Statement	MFL	Broward	41 min
Feb 19, 2:54 PM EST	Special Marine Warning	MFL		51 min
Feb 19, 2:58 PM EST	Areal Flood Advisory	MFL	Broward, Miami-Dade	4 hr
Feb 19, 3:17 PM EST	Special Weather Statement	MFL	Broward	43 min

Nearby

Special Marine Warnings in Florida, 2021 Every special marine warning in 2021

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.