New Marine Weather Message

On Wednesday, August 6, 2008 at 1800 Coordinated Universal Time (UTC), National Weather Service Forecast Offices (WFOs) serving the Atlantic, Pacific, Gulf of Mexico, Caribbean, and Great Lakes coasts began issuing the Marine Weather Message (MWW) operationally.  Selected WFOs have been issuing the MWW experimentally since August 1, 2007. 

The MWW better informs mariners of adverse marine weather hazards and serves as a dedicated long duration marine watch, warning and advisory product.  The MWW implements the operational Valid Time Event Code (VTEC) for all long term marine Watch, Warning and Advisory events.  This includes the implementation of five new marine watch events.  The MWW is patterned after the winter weather watch/warning/advisory bulletin (WSW) and the non-precipitation watch/warning/advisory bulletin (NPW).

The MWW does not include information on short duration events such as severe thunderstorms and waterspouts or for tropical cyclones.

Prior to August 6, 2008, National Weather Service WFOs issued marine warnings and advisories via VTEC in the Coastal Waters Forecast (CWF) and the Nearshore Marine Forecast (NSH). Operational VTEC in the CWF and NSH were discontinued on August 6, 2008 at 1800 UTC.  The five new marine watch headlines are now also included in the CWF and NSH for those WFO's issuing the MWW.

Current MWW products

This product contains the following suite of marine watch, warning and advisory events:

Marine Watches

• Hurricane Force Wind Watch
• Storm Watch
• Gale Watch
• Hazardous Seas Watch
• Heavy Freezing Spray Watch

Marine Warnings

• Hurricane Force Wind Warning
• Storm Warning
• Gale Warning
• Hazardous Seas Warning
• Heavy Freezing Spray Warning

Marine Advisories

• Ashfall Advisory
• Brisk Wind Advisory
• Dense Fog Advisory
• Dense Smoke Advisory
• Freezing Spray Advisory
• Low Water Advisory
• Small Craft Advisory
• Small Craft Advisory for Hazardous Seas
• Small Craft Advisory for Rough Bar
• Small Craft Advisory for Winds

Service Change Notifications (posted at www.nws.noaa.gov/om/notif.htm

• DISCONTINUATION OF THE VALID TIME EVENT CODE /VTEC/ IN THE COASTAL WATERS FORECAST (CWF) AND NEARSHORE MARINE FORECAST (NSH): EFFECTIVE AUGUST 5, 2008
• OPERATIONAL IMPLEMENTATION OF THE MARINE WEATHER MESSAGE (MWW): EFFECTIVE AUGUST 5, 2008
• NEW CALL TO ACTION /CTA/ MARKERS IN THE OPERATIONAL MARINE WEATHER MESSAGE (MWW): EFFECTIVE AUGUST 5, 2008
• DELAY IN SIMULTANEOUS DISCONTINUATION OF VALID TIME EVENT CODE IN COASTAL WATERS AND NEARSHORE MARINE FORECASTS AND IMPLEMENTATION OF MARINE WEATHER MESSAGE PRODUCT

MWW Presentations

• Partners Meeting June 2008
• AMS 88th Annual Meeting
•  24th Conference on IIPS - Session 7A:
• Extended abstract
• Recorded Presentation
• National Marine Program Leaders Meeting
• Partners Meeting June 2007
• MWW WFO Training

MWW Directive

• Official NWSI 10-315, Marine Weather Message

Users must add the following product headers to their communications databases to begin receiving the MWW:
 

        
More detailed information on the marine weather message product is provided in the product description document posted at: http://www.weather.gov/os/mww/MWW_PDD.pdf

Users of the product are encouraged to provide feedback by using the brief survey and comment form available online at:http://www.weather.gov/survey/nws-survey.php?code=mww

MWW Example

WHUS76 KMFR 081505
MWWMFR

URGENT – MARINE WEATHER MESSAGE
NATIONAL WEATHER SERVICE MEDFORD OR
805 AM PDT FRI AUG 8 2008

...GALE WARNING IN EFFECT UNTIL 9 PM PST THIS EVENING...

.WINDS WILL INCREASE LATE THIS MORNING AHEAD OF AN APPROACHING
STRONG COLD FRONT THAT WILL REACH THE COAST BY LATE AFTERNOON.
SOUTH WINDS WILL INCREASE TO GALES LATE THIS MORNING. AFTER THE
FRONT PASSES THROUGH THE WATERS WINDS WILL BECOME NORTHWEST
AND DIMINISH BELOW GALES TO SMALL CRAFT ADVISORY WINDS.

PZZ350-082300-
/O.NEW.KMFR.GL.W.0001.080808T1600Z-080809T0500Z/
COASTAL WATERS FROM FLORENCE TO CAPE BLANCO OR OUT 20 NM-
705 AM PST FRI AUG 8 2008

...GALE WARNING IN EFFECT UNTIL 9 PM PST THIS EVENING...

THE NATIONAL WEATHER SERVICE IN MEDFORD HAS ISSUED A GALE
WARNING...WHICH IS IN EFFECT UNTIL 9 PM THIS EVENING.

SOUTH WINDS WILL INCREASE LATE THIS MORNING AHEAD OF A COLD
FRONT...WITH EXPECTED WINDS OF 35 TO 40 KT WITH GUSTS TO 45 KT.
WINDS WILL BECOME NORTHWEST AND DIMINISH BELOW GALES BEHIND
THE FRONT LATE THIS EVENING.

PRECAUTIONARY/PREPAREDNESS ACTIONS…

A GALE WARNING MEANS WINDS OF 34 TO 47 KNOTS ARE IMMINENT OR
OCCURING. 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.

&&

If you have additional questions on the MWW bulletin, contact: