NOUS41 KWBC 011725
Service Change Notice 12-27
National Weather Service Headquarters Washington DC
125 PM EDT Wed Aug 1 2012
-Family of Services
-NOAA Weather Wire Service
-Emergency Managers Weather Information Network
FROM: Mark Tew
Branch Chief, Marine and Coastal Weather Services
SUBJECT: New Experimental Wave Terminology Change to be used
For Coastal Waters from Point Saint George to
Point Arena, CA, Effective September 19, 2012
Effective Wednesday September 19, 2012, at 900
AM Pacific Daylight Time (PDT), 12 noon Eastern Daylight Time (EDT),
Areas affected include the coastal waters from Point Saint George to Point Arena, California. The purpose of the change is to evaluate the following wave terminology:
Sea state will be described by providing a total wave height along with additional detailed wave information when it is useful for the mariner. The amount of detailed wave information provided will depend on conditions. For example, when there is only a single wave, then that wave’s direction, height and period will be given. For example:
SEAS NW 6 TO 8 FT AT 10 SECONDS
When there are two distinct waves, then the total wave height will still be given, but the two waves that make up that sea state will also be described. For example:
SEAS 8 TO 10 FT...INCLUDING NW 7 FT AT 10 SECONDS AND SW 5 FT AT 14 SECONDS
When there are too many waves present to provide detailed information about each wave, the term CONFUSED will be used to let the mariner know that waves from many directions are present. Total wave height will be provided with the period from the biggest wave. For example:
CONFUSED SEAS 8 TO 10 FT AT 10 SECONDS
In some circumstances, only a total wave height will be provided without including direction and period. For example, when the sea state is very small or the forecast area is so large that there is great variability of the wave direction and period, only a total wave height may be given. For example:
SEAS 1 TO 2 FT
Finally, an example of a 5-day forecast from the Eureka, CA WFO may read:
TODAY...NW WIND 5 TO 15 KT. SEAS NW 6 TO 8 FT AT 10 SECONDS.
TONIGHT...N WIND 10 TO 20 KT. SEAS 7 TO 9 FT...INCLUDING N 3 FT AT 4 SECONDS AND NW 7 FT AT 11 SECONDS.
SAT...N WIND 10 TO 20 KT. SEAS 8 TO 10 FT...INCLUDING N 4 FT AT 4 SECONDS AND NW 7 FT AT 10 SECONDS.
SAT NIGHT...N WIND 20 TO 25 KT. SEAS 9 TO 11 FT...INCLUDING N 7 FT AT 6 SECONDS AND 6 FT AT 10 SECONDS.
SUN...N WIND 20 TO 30 KT WITH GUSTS TO 40 KT. SEAS N 9 TO 11 FT AT 9 SECONDS.
MON...N WIND 20 TO 30 KT WITH GUSTS TO 35 KT. SEAS N 9 TO 11 FT AT 9 SECONDS.
TUE...N WIND 15 TO 25 KT WITH GUSTS TO 30 KT. SEAS 7 TO 9 FT...INCLUDING N 6 FT AT 6 SECONDS AND W 5 FT AT 11 SECONDS.
The terms WIND WAVE and SWELL will no longer be used because the characteristics of the sea state will be communicated by using the more descriptive direction, height, and period of the individual wave system. The motivation for this change and a simple explanation of the significance of wave direction, height, and period is available at:
The evaluation of the wave terminology will run at least through July 31, 2013.
If response is favorable, the NWS will consider expanding the test to other portions of the nation. These changes may be made permanent if the test results are favorable. If the test results are not favorable, the wave portion of the coastal waters forecast will revert to the previous method. Users are encouraged to provide feedback on this change to the marine forecast by using the brief survey and comment form available at:
Table 1 lists products issued by WFO Eureka affected by this change beginning September 19, 2012
Table 1: WFO EUREKA PRODUCTS
Product Name AWIPS ID
COASTAL WATERS FORECAST CWFEKA FZUS56 KEKA
Table 2 contains lists of the current marine zones affected by the change in WFO Eureka Coastal Waters Forecast (CWF).
Table 2: Affected marine zones and corresponding UGCs for WFO Eureka
Current Marine Zone Name Current UGC
PT ST GEORGE TO CAPE MENDOCINO...OUT 10 NM PZZ450
PT ST GEORGE TO CAPE MENDOCINO...10 TO 60 NM PZZ470
CAPE MENDOCINO TO PT ARENA...OUT 10 NM PZZ455
CAPE MENDOCINO TO PT ARENA...10 TO 60 NM PZZ475
Users do not need to make any changes to their systems in order to continue to receive the Coastal Waters Forecast (CWF) product from WFO Eureka.
For questions or comments about this change, contact:
Warning Coordination Meteorologist
NOAA National Weather Service
Eureka, CA 95501-6000
707-443-6484 x 223
NWS Public Information Statements are online at: