NATIONAL WEATHER SERVICE RETIRES ITS
COASTAL WARNING DISPLAY PROGRAM
As of February 15, 1989, the National Weather Service retired
its Coastal Warning Display network nationwide.
For over 100 years, display stations were established at
yacht clubs, marinas, and Coast Guard stations to hoist
flags, pennants and colored lights to warn mariners of storms
at sea. The display stations were individually notified
by the National Weather Service to raise the signals and
again to lower them when the hazards passed. The National
Weather Service paid for the visual signals; however, the
display stations were operated by other agencies or volunteers.
Although the Coastal Warning Display program has been formally
discontinued, U.S. Coast Guard and other stations may continue
to display warning signals without the direct participation
of the National Weather Service.
News - Beginning June 1, 2007, U.S. Coast Guard formally re-established a Coastal Warning Display program at selected small boat stations which will hoist display flags to warn of small craft advisories, gale warnings, storm warnings and hurricane warnings.
The Coastal Warning Display program was de-emphasized in
favor of frequently updated telephone
recordings and NOAA Weather Radio. The latter covers
the coastal areas of continental United States, Alaska,
Hawaii, and the Mariana Islands with continuous weather
broadcasts. The major shortcomings of the Coastal Warning
Display program were that the displays reached only the
small portion of the marine public within sight of them;
it cannot convey specific information on movement, intensity,
and duration; and the time required to notify the sites
by individual telephone calls takes the forecaster away
from critical tasks associated with the weather. Further,
when users perceive them to be a full substitute for NOAA
Weather Radio, other radio broadcasts, and the telephone
recordings, they are actually being a disservice.
Coastal Warning Display Signals
DAYTIME SIGNALS
SMALL CRAFT ADVISORY
![SMALL CRAFT ADVISORY](images/smcraft.gif) |
GALE WARNING
![gale warning](images/gale.gif) |
STORM WARNING
![STORM WARNING](images/storm.gif) |
HURRICANE WARNING
![HURRICANE WARNING](images/mhurr.gif) |
NIGHT (LIGHT) SIGNALS
SMALL CRAFT ADVISORY
![SMALL CRAFT ADVISORY](images/nsmcraft.gif) |
GALE WARNING
![GALE WARNING](images/ngale.gif) |
STORM WARNING
![STORM WARNING](images/nstorm.gif) |
HURRICANE WARNING
![HURRICANE WARNING](images/nhurr.gif) |
Explanation of Warnings
SMALL CRAFT ADVISORY: An advisory issued by coastal and Great Lakes Weather Forecast Offices (WFO) for areas included in the Coastal Waters Forecast or Nearshore Marine Forecast (NSH) products. Thresholds governing the issuance of small craft advisories are specific to geographic areas. A Small Craft Advisory may also be issued when sea or lake ice exists that could be hazardous to small boats. There is no precise definition of a small craft. Any vessel that may be adversely affected by Small Craft Advisory criteria should be considered a small craft. Other considerations include the experience of the vessel operator, and the type, overall size, and sea worthiness of the vessel.
There is no legal definition of "small craft". The Small Craft Advisory is an advisory in Coastal Waters and Nearshore forecasts for sustained winds, frequent gusts, or sea/wave conditions, exceeding defined thresholds specific to geographic areas. A Small Craft Advisory may also be issued when sea or lake ice exists that could be hazardous to small boats.
Eastern (ME..SC, Lake Erie, Lake Ontario) - Sustained winds or frequent gusts ranging between 25 and 33 knots
(except 20 to 25 knots, lower threshold area dependent, to 33 knots for
harbors, bays, etc.) and/or seas or waves 5 to 7 feet and greater, area
dependent.
Central (MN..OH) - Sustained winds or frequent gusts (on the Great Lakes) between 22
and 33 knots inclusive, and/or seas or waves greater than 4 feet.
Southern (GA..TX and Caribbean) - Sustained winds of 20 to 33 knots, and/or forecast seas 7 feet or
greater that are expected for more than 2 hours.
Western (WA..CA) - Sustained winds of 21 to 33 knots, potentially in combination with
wave heights exceeding 10 feet (or wave steepness values exceeding
local thresholds).
Alaska (AK) - Sustained winds or frequent gusts of 23 to 33 knots. A small craft
advisory for rough seas may be issued for sea/wave conditions deemed
locally significant, based on user needs, and should be no lower than 8
feet.
Hawaii (HI), Samoa - Sustained winds 25 knots or greater and seas 10 feet or greater.
Guam and the Northern Mariana Islands - Sustained winds 22 to 33 knots and/or combined seas of 10 feet or more.
“Frequent gusts”are typically long duration conditions (greater than 2 hours).
For a list of NWS Weather Offices by Region, refer to the following website:
http://www.nws.noaa.gov/organization.php
GALE WARNING: To indicate winds within the range
34 to 47 knots are forecast for the area.
STORM WARNING: To indicate winds 48 knots and above,
no matter how high the speed, are forecast for the area.
However, if the winds are associated with a tropical cyclone
(hurricane), the STORM WARNING indicates that winds within
the range 48-63 knots are forecast.
HURRICANE WARNING: An announcement that hurricane conditions (sustained winds of 74 mph or higher) are expected somewhere within the specified coastal area. Because hurricane preparedness activities become difficult once winds reach tropical storm force, the hurricane warning is issued 36 hours in advance of the anticipated onset of tropical-storm-force winds.
NOTE: A "HURRICANE WATCH" is an announcement that hurricane conditions (sustained winds of 74 mph or higher) are possible within the specified coastal area. Because hurricane preparedness activities become difficult once winds reach tropical storm force, the hurricane watch is issued 48 hours in advance of the anticipated onset of tropical-storm-force winds.
NOTE: A SPECIAL MARINE WARNING is issued whenever
a severe local storm or strong wind of brief duration is
imminent and is not covered by existing warnings or advisories.
No visual displays will be used in connection with the Special
Marine Warning Bulletin; boaters will be able to receive
these special warnings by keeping tuned to a NOAA Weather
Radio station or to Coast Guard and commercial radio stations
that transmit marine weather information.
|