Alert archive / California / Hazardous Seas Warnings in 2018

Hazardous Seas Warning 21, NWS Eureka, CA

December 19, 2018

NWS Eureka, CA issued this hazardous seas warning at Dec 19, 2018, 9:04 AM PST. It took effect at Dec 19, 2018, 12:00 PM PST. It was in force for 19 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Dec 19, 2018, 9:04 AM PST (17:04 UTC)
In effect from
Dec 19, 2018, 12:00 PM PST
Expired
Dec 20, 2018, 7:00 AM PST
In force
19 hr
Issued by
NWS Eureka, CA

The text

As transmitted.

443 
WHUS76 KEKA 191704
MWWEKA

Urgent - Marine Weather Message
National Weather Service Eureka CA
904 AM PST Wed Dec 19 2018

PZZ450-200115-
/O.EXT.KEKA.SC.Y.0110.000000T0000Z-181219T2000Z/
/O.NEW.KEKA.SE.W.0021.181219T2000Z-181220T1500Z/
/O.CON.KEKA.GL.W.0040.181220T1500Z-181220T2100Z/
Pt St George to Cape Mendocino out 10 nm-
904 AM PST Wed Dec 19 2018

...SMALL CRAFT ADVISORY NOW IN EFFECT UNTIL NOON PST TODAY...
...HAZARDOUS SEAS WARNING IN EFFECT FROM NOON TODAY TO 7 AM PST
THURSDAY...
...GALE WARNING REMAINS IN EFFECT FROM 7 AM TO 1 PM PST
THURSDAY...

The National Weather Service in Eureka has issued a Hazardous
Seas Warning, which is in effect from noon today to 7 AM PST
Thursday. 

* WINDS...Southerly 10 to 20 kt today. Strong southerly winds 25
  to 35 kt will return again tonight and Thursday. 

* Waves/seas...West swell building to 15 to 18 feet 18 seconds by
  late afternoon today. In addition...Steep southerly waves of 6
  to 9 feet building tonight through Thursday.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners, especially those operating smaller
vessels should avoid navigating in these conditions.

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

A Hazardous Seas Warning means hazardous sea conditions are
imminent or occurring. Recreational boaters should remain in
port, or take shelter until waves subside.  Commercial vessels
should prepare for rough seas and consider remaining in port or
taking shelter in port until hazardous seas subside.

&&

$$

PZZ470-200115-
/O.EXT.KEKA.SC.Y.0110.000000T0000Z-181219T2000Z/
/O.NEW.KEKA.SE.W.0021.181219T2000Z-181220T0900Z/
/O.CON.KEKA.GL.W.0040.181220T0900Z-181220T2100Z/
Pt St George to Cape Mendocino 10 to 60 nm-
904 AM PST Wed Dec 19 2018

...SMALL CRAFT ADVISORY NOW IN EFFECT UNTIL NOON PST TODAY...
...HAZARDOUS SEAS WARNING IN EFFECT FROM NOON TODAY TO 1 AM PST
THURSDAY...
...GALE WARNING REMAINS IN EFFECT FROM 1 AM TO 1 PM PST
THURSDAY...

The National Weather Service in Eureka has issued a Hazardous
Seas Warning, which is in effect from noon today to 1 AM PST
Thursday. 

* WINDS...Southerly 10 to 10 kt today. South winds will increase 
  again to 25 to 40 kt Wednesday night Thursday. 

* Waves/seas...West swell building to 15 to 18 feet 18 seconds by
  late afternoon today. In addition...Steep southerly waves of 9
  to 11 feet building tonight through Thursday.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners, especially those operating smaller
vessels should avoid navigating in these conditions.

A Hazardous Seas Warning means hazardous sea conditions are
imminent or occurring. Recreational boaters should remain in
port, or take shelter until waves subside.  Commercial vessels
should prepare for rough seas and consider remaining in port or
taking shelter in port until hazardous seas subside.

&&

$$

PZZ475-200115-
/O.CON.KEKA.SC.Y.0110.000000T0000Z-181220T1500Z/
/O.CON.KEKA.GL.W.0040.181220T1500Z-181220T2100Z/
Cape Mendocino to Pt Arena 10 to 60 nm-
904 AM PST Wed Dec 19 2018

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 7 AM PST
THURSDAY...
...GALE WARNING REMAINS IN EFFECT FROM 7 AM TO 1 PM PST
THURSDAY...

* WINDS...Southerly 10 to 15 kt today. Strong southerly winds 20 
  to 30 kt will return again tonight and Thursday. 

* Waves/seas...West swell building to 14 to 17 feet 18 seconds by
  late afternoon today. In addition...Steep southerly waves of 6
  to 9 feet building tonight through Thursday. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners, especially those operating smaller
vessels should avoid navigating in these conditions.

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

&&

$$

PZZ455-200115-
/O.CON.KEKA.SC.Y.0110.000000T0000Z-181221T2100Z/
Cape Mendocino to Pt Arena out 10 nm-
904 AM PST Wed Dec 19 2018

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 1 PM PST FRIDAY...

* WINDS...Southerly 10 to 15 kt today. Fresh southerly winds 15 
  to 25 kt will return again tonight and Thursday. 

* Waves/seas...West swell building to 14 to 17 feet 18 seconds by
  late afternoon today. In addition...Steep southerly waves of 6
  to 8 feet building tonight through Thursday near Cape Mendocino.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners, especially those operating smaller
vessels should avoid navigating in these conditions.

&&

$$
5 follow-up statements
294 
WHUS76 KEKA 192348
MWWEKA

Urgent - Marine Weather Message
National Weather Service Eureka CA
348 PM PST Wed Dec 19 2018

PZZ450-200800-
/O.CON.KEKA.SE.W.0021.000000T0000Z-181220T1500Z/
/O.CON.KEKA.GL.W.0040.181220T1500Z-181220T2100Z/
Pt St George to Cape Mendocino out 10 nm-
348 PM PST Wed Dec 19 2018

...HAZARDOUS SEAS WARNING REMAINS IN EFFECT UNTIL 7 AM PST
THURSDAY...
...GALE WARNING REMAINS IN EFFECT FROM 7 AM TO 1 PM PST
THURSDAY...

* WINDS...Southerly rising to 10 to 20 kt overnight. Strong 
  southerly winds 25 to 35 kt on Thursday. 

* Waves/seas...West swell building to 15 to 18 feet 18 seconds. In
  addition...Steep southerly waves of 6 to 9 feet building on 
  Thursday. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners, especially those operating smaller
vessels should avoid navigating in these conditions.

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

A Hazardous Seas Warning means hazardous sea conditions are
imminent or occurring. Recreational boaters should remain in
port, or take shelter until waves subside.  Commercial vessels
should prepare for rough seas and consider remaining in port or
taking shelter in port until hazardous seas subside.

&&

$$

PZZ470-200800-
/O.CON.KEKA.SE.W.0021.000000T0000Z-181220T0900Z/
/O.CON.KEKA.GL.W.0040.181220T0900Z-181220T2100Z/
Pt St George to Cape Mendocino 10 to 60 nm-
348 PM PST Wed Dec 19 2018

...HAZARDOUS SEAS WARNING REMAINS IN EFFECT UNTIL 1 AM PST
THURSDAY...
...GALE WARNING REMAINS IN EFFECT FROM 1 AM TO 1 PM PST
THURSDAY...

* WINDS...Southerly rising to 15 to 25 kt overnight. South winds
  will increase further to 25 to 35 kt on Thursday. 

* Waves/seas...West swell building to 15 to 18 feet 18 seconds. In
  addition...Steep southerly waves building to 9 to 11 feet on 
  Thursday. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners, especially those operating smaller
vessels should avoid navigating in these conditions.

A Hazardous Seas Warning means hazardous sea conditions are
imminent or occurring. Recreational boaters should remain in
port, or take shelter until waves subside.  Commercial vessels
should prepare for rough seas and consider remaining in port or
taking shelter in port until hazardous seas subside.

&&

$$

PZZ475-200800-
/O.CON.KEKA.SC.Y.0110.000000T0000Z-181220T1500Z/
/O.CON.KEKA.GL.W.0040.181220T1500Z-181220T2100Z/
Cape Mendocino to Pt Arena 10 to 60 nm-
348 PM PST Wed Dec 19 2018

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 7 AM PST
THURSDAY...
...GALE WARNING REMAINS IN EFFECT FROM 7 AM TO 1 PM PST
THURSDAY...

* WINDS...Southerly 10 to 20 kt tonight. Strong southerly winds 
  20 to 30 kt with gusts to 35 kt on Thursday. 

* Waves/seas...West swell building to 14 to 17 feet 18 seconds. 
  In addition...Steep southerly waves of 6 to 9 feet building 
  late tonight through Thursday. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners, especially those operating smaller
vessels should avoid navigating in these conditions.

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

&&

$$

PZZ455-200800-
/O.CON.KEKA.SC.Y.0110.000000T0000Z-181221T2100Z/
Cape Mendocino to Pt Arena out 10 nm-
348 PM PST Wed Dec 19 2018

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 1 PM PST FRIDAY...

* WINDS...Southerly 5 to 15 kt today. Fresh southerly winds 15 to
  25 kt on Thursday. 

* Waves/seas...West swell building to 14 to 17 feet 18 seconds by
  late afternoon tonight. In addition...Steep southerly waves of 6
  to 8 feet building on Thursday near Cape Mendocino.
  

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners, especially those operating smaller
vessels should avoid navigating in these conditions.

&&

$$
697 
WHUS76 KEKA 200517
MWWEKA

Urgent - Marine Weather Message
National Weather Service Eureka CA
917 PM PST Wed Dec 19 2018

PZZ450-201330-
/O.CON.KEKA.SE.W.0021.000000T0000Z-181220T1500Z/
/O.CON.KEKA.GL.W.0040.181220T1500Z-181220T2100Z/
Pt St George to Cape Mendocino out 10 nm-
917 PM PST Wed Dec 19 2018

...HAZARDOUS SEAS WARNING REMAINS IN EFFECT UNTIL 7 AM 
THURSDAY... 
...GALE WARNING REMAINS IN EFFECT FROM 7 AM TO 1 PM 
THURSDAY...

* WINDS...S 10 to 20 kt overnight. Strong southerly winds 25 to 
  35 kt on Thursday. 

* WAVES...W swell building to 15 to 18 ft 18 seconds. In
  addition...steep southerly waves of 6 to 9 ft building on 
  Thursday. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

A Hazardous Seas Warning means hazardous sea conditions are
imminent or occurring. Recreational boaters should remain in
port, or take shelter until waves subside.  Commercial vessels
should prepare for rough seas and consider remaining in port or
taking shelter in port until hazardous seas subside.

$$

PZZ470-201330-
/O.CON.KEKA.SE.W.0021.000000T0000Z-181220T0900Z/
/O.CON.KEKA.GL.W.0040.181220T0900Z-181220T2100Z/
Pt St George to Cape Mendocino 10 to 60 nm-
917 PM PST Wed Dec 19 2018

...HAZARDOUS SEAS WARNING REMAINS IN EFFECT UNTIL 1 AM
THURSDAY... 
...GALE WARNING REMAINS IN EFFECT FROM 1 AM TO 1 PM 
THURSDAY...

* WINDS...S rising to 15 to 25 kt overnight. S winds will 
  increase further to 25 to 35 kt on Thursday. 

* WAVES...W swell building to 15 to 18 ft 18 seconds. In 
  addition...steep southerly waves building to 9 to 11 ft on 
  Thursday

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

A Hazardous Seas Warning means hazardous sea conditions are
imminent or occurring. Recreational boaters should remain in
port, or take shelter until waves subside.  Commercial vessels
should prepare for rough seas and consider remaining in port or
taking shelter in port until hazardous seas subside.

$$

PZZ475-201330-
/O.CON.KEKA.SC.Y.0110.000000T0000Z-181220T1500Z/
/O.CON.KEKA.GL.W.0040.181220T1500Z-181220T2100Z/
Cape Mendocino to Pt Arena 10 to 60 nm-
917 PM PST Wed Dec 19 2018

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 7 AM THURSDAY... 
...GALE WARNING REMAINS IN EFFECT FROM 7 AM TO 1 PM THURSDAY...

* WINDS...S 10 to 20 kt tonight. Strong southerly winds 20 to 30 
  kt with gusts to 35 kt on Thursday. 

* WAVES...W swell building to 14 to 17 ft 18 seconds. In
  addition...steep southerly waves of 6 to 9 ft building late 
  tonight through Thursday. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners, especially those operating smaller
vessels should avoid navigating in these conditions.

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

$$

PZZ455-201330-
/O.CON.KEKA.SC.Y.0110.000000T0000Z-181221T2100Z/
Cape Mendocino to Pt Arena out 10 nm-
917 PM PST Wed Dec 19 2018

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 1 PM FRIDAY...

* WINDS...S 15 to 25 kt on Thursday. 

* WAVES...W swell building to 14 to 17 ft 18 seconds tonight. In
  addition...steep southerly waves of 6 to 8 ft building on 
  Thursday near Cape Mendocino. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners, especially those operating smaller
vessels should avoid navigating in these conditions.

$$
910 
WHUS76 KEKA 200848
MWWEKA

Urgent - Marine Weather Message
National Weather Service Eureka CA
1248 AM PST Thu Dec 20 2018

PZZ470-201700-
/O.EXP.KEKA.SE.W.0021.000000T0000Z-181220T0900Z/
/O.CON.KEKA.GL.W.0040.181220T0900Z-181220T2100Z/
Pt St George to Cape Mendocino 10 to 60 nm-
1248 AM PST Thu Dec 20 2018

...GALE WARNING REMAINS IN EFFECT UNTIL 1 PM PST THIS AFTERNOON...

* WINDS...S rising to 15 to 25 kt overnight. S winds will 
  increase further to 25 to 35 kt on Thursday. 

* WAVES...W swell building to 15 to 17 ft 18 seconds. In
  addition...steep southerly waves building to 9 to 11 ft on
  Thursday morning

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

&&

$$

PZZ450-201700-
/O.CON.KEKA.SE.W.0021.000000T0000Z-181220T1500Z/
/O.CON.KEKA.GL.W.0040.181220T1500Z-181220T2100Z/
Pt St George to Cape Mendocino out 10 nm-
1248 AM PST Thu Dec 20 2018

...HAZARDOUS SEAS WARNING REMAINS IN EFFECT UNTIL 7 AM PST THIS
MORNING...
...GALE WARNING REMAINS IN EFFECT FROM 7 AM THIS MORNING TO 1 PM
PST THIS AFTERNOON...

* WINDS...S 10 to 20 kt overnight. Strong southerly winds 25 to 
  35 kt on Thursday. 

* WAVES...W swell building to 15 to 18 ft 18 seconds. In 
  addition...steep southerly waves of 6 to 9 ft building on 
  Thursday. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

A Hazardous Seas Warning means hazardous sea conditions are
imminent or occurring. Recreational boaters should remain in
port, or take shelter until waves subside.  Commercial vessels
should prepare for rough seas and consider remaining in port or
taking shelter in port until hazardous seas subside.

$$

PZZ475-201700-
/O.CON.KEKA.SC.Y.0110.000000T0000Z-181220T1500Z/
/O.CON.KEKA.GL.W.0040.181220T1500Z-181220T2100Z/
Cape Mendocino to Pt Arena 10 to 60 nm-
1248 AM PST Thu Dec 20 2018

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 7 AM PST THIS
MORNING...
...GALE WARNING REMAINS IN EFFECT FROM 7 AM THIS MORNING TO 1 PM
PST THIS AFTERNOON...

* WINDS...S 10 to 20 kt tonight. Strong southerly winds 20 to 30 
  kt with gusts to 35 kt on Thursday. 

* WAVES...W swell building to 14 to 17 ft 18 seconds. In 
  addition...steep southerly waves of 6 to 9 ft building late 
  tonight through Thursday. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners, especially those operating smaller
vessels should avoid navigating in these conditions.

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

$$

PZZ455-201700-
/O.CON.KEKA.SC.Y.0110.000000T0000Z-181221T2100Z/
Cape Mendocino to Pt Arena out 10 nm-
1248 AM PST Thu Dec 20 2018

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 1 PM PST FRIDAY...

* WINDS...S 15 to 25 kt on Thursday.

* WAVES...W swell building to 14 to 17 ft 18 seconds tonight. In 
  addition...steep southerly waves of 6 to 8 ft building on 
  Thursday near Cape Mendocino. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners, especially those operating smaller
vessels should avoid navigating in these conditions.

$$
059 
WHUS76 KEKA 201109
MWWEKA

Urgent - Marine Weather Message
National Weather Service Eureka CA
309 AM PST Thu Dec 20 2018

PZZ450-201915-
/O.CON.KEKA.SE.W.0021.000000T0000Z-181220T1500Z/
/O.CON.KEKA.GL.W.0040.181220T1500Z-181220T2100Z/
Pt St George to Cape Mendocino out 10 nm-
309 AM PST Thu Dec 20 2018

...HAZARDOUS SEAS WARNING REMAINS IN EFFECT UNTIL 7 AM PST THIS
MORNING...
...GALE WARNING REMAINS IN EFFECT FROM 7 AM THIS MORNING TO 1 PM
PST THIS AFTERNOON...

* WINDS...Strong southerly winds 25 to 35 kt. 

* WAVES...W swell building to 12 to 14 ft at 15 seconds. In
  addition...steep southerly waves of 7 to 9 ft building today. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

A Hazardous Seas Warning means hazardous sea conditions are
imminent or occurring. Recreational boaters should remain in
port, or take shelter until waves subside.  Commercial vessels
should prepare for rough seas and consider remaining in port or
taking shelter in port until hazardous seas subside.

$$

PZZ475-201915-
/O.CON.KEKA.SC.Y.0110.000000T0000Z-181220T1500Z/
/O.CON.KEKA.GL.W.0040.181220T1500Z-181220T2100Z/
Cape Mendocino to Pt Arena 10 to 60 nm-
309 AM PST Thu Dec 20 2018

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 7 AM PST THIS
MORNING...
...GALE WARNING REMAINS IN EFFECT FROM 7 AM THIS MORNING TO 1 PM
PST THIS AFTERNOON...

* WINDS...Strong southerly winds 20 to 30 kt with gusts to 40 kt.
  

* WAVES...W swell building to 12 to 14 ft 15 seconds. In
  addition...steep southerly waves of 8 to 10 ft building today. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners, especially those operating smaller
vessels should avoid navigating in these conditions.

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

$$

PZZ470-201915-
/O.CON.KEKA.GL.W.0040.000000T0000Z-181220T2100Z/
Pt St George to Cape Mendocino 10 to 60 nm-
309 AM PST Thu Dec 20 2018

...GALE WARNING REMAINS IN EFFECT UNTIL 1 PM PST THIS AFTERNOON...

* WINDS... S winds 25 to 35 kt 

* WAVES...W swell building to 11 to 13 ft 16 seconds. In
  addition...steep southerly waves building to 8 to 10 ft today.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

&&

$$

PZZ455-201915-
/O.CON.KEKA.SC.Y.0110.000000T0000Z-181221T2100Z/
Cape Mendocino to Pt Arena out 10 nm-
309 AM PST Thu Dec 20 2018

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 1 PM PST FRIDAY...

* WINDS...S winds 15 to 25 kt 

* WAVES...W swell building to 11 to 13 ft 16 seconds tonight. In
  addition...steep southerly waves of 6 to 8 ft building today... 
  largest near Cape Mendocino. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners, especially those operating smaller
vessels should avoid navigating in these conditions.

$$
070 
WHUS76 KEKA 201447
MWWEKA

Urgent - Marine Weather Message
National Weather Service Eureka CA
647 AM PST Thu Dec 20 2018

PZZ450-202100-
/O.EXP.KEKA.SE.W.0021.000000T0000Z-181220T1500Z/
/O.CON.KEKA.GL.W.0040.181220T1500Z-181220T2100Z/
Pt St George to Cape Mendocino out 10 nm-
647 AM PST Thu Dec 20 2018

...GALE WARNING REMAINS IN EFFECT UNTIL 1 PM PST THIS AFTERNOON...

* WINDS...Strong southerly winds 25 to 35 kt.

* WAVES...W swell building to 12 to 14 ft at 15 seconds. In 
  addition...steep southerly waves of 7 to 9 ft building today. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

&&

$$

PZZ475-202100-
/O.EXP.KEKA.SC.Y.0110.000000T0000Z-181220T1500Z/
/O.CON.KEKA.GL.W.0040.181220T1500Z-181220T2100Z/
Cape Mendocino to Pt Arena 10 to 60 nm-
647 AM PST Thu Dec 20 2018

...GALE WARNING REMAINS IN EFFECT UNTIL 1 PM PST THIS AFTERNOON...

* WINDS...Strong southerly winds 20 to 30 kt with gusts to 40 kt.

* WAVES...W swell building to 12 to 14 ft 15 seconds. In 
  addition...steep southerly waves of 8 to 10 ft building today. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

&&

$$

PZZ470-202100-
/O.CON.KEKA.GL.W.0040.000000T0000Z-181220T2100Z/
Pt St George to Cape Mendocino 10 to 60 nm-
647 AM PST Thu Dec 20 2018

...GALE WARNING REMAINS IN EFFECT UNTIL 1 PM PST THIS AFTERNOON...

* WINDS... S winds 25 to 35 kt

* WAVES...W swell building to 11 to 13 ft 16 seconds. In 
  addition...steep southerly waves building to 8 to 10 ft today. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Gale Warning means winds of 34 to 47 knots are imminent or
occurring. Operating a vessel in gale conditions requires
experience and properly equipped vessels. It is highly
recommended that mariners without the proper experience seek safe
harbor prior to the onset of gale conditions.

&&

$$

PZZ455-202300-
/O.CON.KEKA.SC.Y.0110.000000T0000Z-181221T2100Z/
Cape Mendocino to Pt Arena out 10 nm-
647 AM PST Thu Dec 20 2018

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 1 PM PST FRIDAY...

* WINDS...S winds 15 to 25 kt

* WAVES...W swell building to 11 to 13 ft 16 seconds tonight. In 
  addition...steep southerly waves of 6 to 8 ft building today...
   largest near Cape Mendocino. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners, especially those operating smaller
vessels should avoid navigating in these conditions.

$$

The office that day

Everything else NWS Eureka, CA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 19, 4:24 AM PSTGale WarningEKA33 hr
Dec 19, 9:06 AM PSTHigh Surf AdvisoryEKADel Norte, Humboldt, Mendocino18 hr

Nearby

Hazardous Seas Warnings in California, 2018Every hazardous seas warning in 2018

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text.