National Weather Service Marine Forecasts

Go the National Weather Service's Marine Forecasts webpage. This page also provides links to Marine Forecast Offices and Centers which provide links to their products, as well as additional regionally focused information such as buoy observations and tide predictions.

The Marine Forecasts - Products Via Internet webpage provides details on where to find marine related weather products, publications and information on the Internet. This webpage also provides links to Foreign Meteorological Services and Computer Generated Model Guidance which includes data which is outside the area of U.S. marine forecast responsibility.

2. How can I get a marine forecast or buoy observation over the phone?

Most National Weather Service offices keep an updated recording of the forecasts they produce and can be accessed by phone. To find the phone number of the office near you, check your telephone directory under "United States Government, Commerce Department, National Weather Service." A listing of Weather Service Offices with marine recordings is also available. Current buoy and C-MAN observations may also be obtained by phone via NDBC's "Dial-A-Buoy"service.

3. How can I get a marine forecast or buoy observation via E-mail?

To get started in using the NWS FTPMAIL service, follow these simple directions to obtain the FTPMAIL "help" file, or see: http://weather.noaa.gov/pub/fax/ftpmail.txt.

Send an e-mail to: ftpmail@weather.noaa.gov

Subject line: Put anything you like

Body: help

A webpage describing several different e-mail "robots" similar in concept to FTPMAIL, including some with advanced features such as allowing retrieval of NWS marine GRIB files, simple webpages, and allowing products to be retrieved on a scheduled, recurring basis may be found at: http://weather.noaa.gov/pub/fax/robots.txt

4. Where can I get information on current marine weather conditions and the tide?

Listen to NOAA Weather Radio, see the webpage of your local Weather Forecast Office, or the National Data Buoy Center (NDBC). Current buoy and C-MAN observations may also be obtained by phone via NDBC's "Dial-A-Buoy" service.

Tide predictions, current predictions, and Real-Time water level measurements are available from the National Ocean Service's CO-OP webpage

5. Where can I get copies of old forecasts or find climatological information?

For the most part, historical marine forecasts are not available on the web and must be ordered for a nominal fee.

For Historic Weather and Satellite Data Contact:

National Climatic Data Center
151 Patton Avenue, room 120
Asheville, NC 28801-5001
828-271-4800
828-271-4876 (FAX)
weborder@ncdc.noaa.gov
http://lwf.ncdc.noaa.gov/oa/ncdc.html

For Historic Oceanographic Data Contact:

National Oceanographic Data Center
User Services
NOAA/NESDIS E/OC1
SSMC3, 4th Floor
1315 East West Highway
Silver Spring, MD 20910-3282
301-713-3277
301-713-3302 (FAX)
services@nodc.noaa.gov
http://www.nodc.noaa.gov

User-friendly climatological information for marine coastal areas may be found in Appendix T of the National Ocean Service's Coast Pilot's, volumes 1-9. These appendices, which were prepared by the National Climatic Data Center, also contain other useful meteorological information such as conversion tables.

The National Geospacial-Intelligence Agency now makes available some of its Pilot Charts, which contain climatological information in graphic form on-line.

6. Where can I find Sea Surface Temperature (SST) and Gulf Stream information on the Web?

Try these sites on the Web for Sea Surface Temperature (SST) and Gulf Stream information.

URL Addresses....pay attention to capitalization

NOAA SOURCES
http://polar.ncep.noaa.gov/sst/
http://polar.ncep.noaa.gov/gsf/
http://www.osdpd.noaa.gov/OSDPD/OSDPD_high_prod.html
http://polar.ncep.noaa.gov/
http://polar.ncep.noaa.gov/cofs/Welcome.html (nowcasts and forecasts)
http://www.cdc.noaa.gov/
http://www.nhc.noaa.gov/aboutsst.shtml
http://www.goes.noaa.gov
http://pafc.arh.noaa.gov/ice.php
http://coastwatch.noaa.gov/COASTWATCH/
http://www.aoml.noaa.gov/phod/uot/
http://www.nodc.noaa.gov/GTSPP/gtspp-home.html
http://www.elnino.noaa.gov/
http://manati.orbit.nesdis.noaa.gov/cgi-bin/ws_sst_day_noaa.pl

NAVY SOURCES
https://www.navo.navy.mil
https://www.fnoc.navy.mil
http://www7300.nrlssc.navy.mil/altimetry/
http://www7320.nrlssc.navy.mil/global_nlom/globalnlom/skill.html

NASA SOURCES
http://seawifs.gsfc.nasa.gov/SEAWIFS/IMAGES/SST.html

UNIVERSITY SOURCES
http://marine.rutgers.edu/mrs/
http://fermi.jhuapl.edu/index.html
http://www.rsmas.miami.edu/images.html
http://www.deos.tudelft.nl/altim/gulfstream/
http://www.thecoolroom.org

DIRECTORY OF PRIVATE WEATHER SERVICES
http://www.nws.noaa.gov/im/index.html

Providers on above webpage which provide Gulfstream information:

Alan Archer
President
Continental Weather Corporation
1407 Hounds Hollow Court
Lutz, FL 33549
PHONE: 813/949-4424 FAX: 813/949-3875
EMAIL: skyarcher@aol.com

Mitchell A. Roffer
President
Roffer's Ocean Fishing Forecasting Service, Inc.
2871 S.W. 69th Court
Miami, FL 33155
PHONE: 800/677-7633 FAX: 305/265-9077
EMAIL: fish@roffs.com
www.roffs.com

Jenifer Clark
Satellite Oceanographer
Jenifer Clark's Gulfstream
5902 Federal Court
Upper Marlboro, MD 20772
PHONE: 301/952-0930 FAX: 301/574-0289
EMAIL: gulfstrm@erols.com

John C. Freeman (CCM)*
Director of Research
Weather Research Center
3227 Audley Street
Houston, TX 77098
PHONE: 800/44-STORM FAX: 713/528-3538
EMAIL: wrc@wxresearch.com

To register a 406 mHz EPIRB or to learn more about EPIRB's contact: NOAA SARSAT E/SP3, RM 3320, FB-4
5200 Auth Road
Suitland MD 20746-4304
301-457-5678
888-212-7283 (Toll Free)
301-568-8649(FAX)
osdpd.dsd.reception@noaa.gov
http://www.sarsat.noaa.gov
http://www.navcen.uscg.gov/marcomms/gmdss/epirb.htm

8. Is the voice I hear on NOAA Weather Radio a computerized voice or a real person?

You are most likely listening to a computer synthesized voice. Efforts are underway to both expand the coverage of the NOAA Weather Radio network and improve the audio quality. If you hear words in a broadcast which need to have the pronunciation adjusted, forward your comments to the appropriate NWS forecast office so they can attempt to improve the pronunciation. Please visit NOAA Weather Radio.

9. I work for a commercial meteorological services company. What options are available to receive NWS forecasts and data without relying on the Internet?

Your three most viable options are NOAAPORT, NOAA WX Wire, and Family of Services.

10. When I'm browsing the Internet and click on one your forecasts, I get an old forecast. What's going on?

Always check the time and date of forecasts. Most marine forecasts are updated every six hours and as conditions warrant. Several types of products are not issued year-round such as recreational and Great Lakes nearshore forecasts. Warning products are generally only issued as required.

You may be unintentionally recalling data from your PC's cashe memory. Use the reload/refresh function of your webbrowser to refresh the webpage.

The Internet is not part of the National Weather Service's operational data stream and should never be relied upon as a means to obtain the latest forecast and warning data. Become familiar with and use other means such as NOAA Weather Radio to obtain the latest forecasts and warnings. Please read our disclaimer.

11. How can I access the Internet or exchange E-mail while at sea?

The Marine Forecasts - Products Via Internet webpage provides information on how mariners may access the Internet and exchange E-mail via radio, cellular, and satellite technologies.

12. It seems like I wait forever to hear a marine forecast on NOAA Weather Radio. What's being done?

The NOAA Weather Radio network is being continually expanded to reduce each transmitters workload and increase coverage. Several NOAA Weather Radio transmitters operate as "Marine-Only", broadcasting marine information on a more rapid cycle than is possible with "All-Hazard" transmitters. These are typically established as part of a cooperative effort between the local marine community and the National Weather Service. For information on how to establish a "Marine-Only" NOAA Weather Radio transmitter in your area, contact the National Weather Service.

13. What is a "Small Craft Advisory", Gale Warning, etc?

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 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/waves 5 to 7 feet and greater, area dependent.

Central (WI..OH) - Sustained winds or frequent gusts between 22 and 33 knots inclusive, and/or seas/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/is expected for more than 2 hours.

Western (WA..CA) - Sustained winds of 21 to 33 knots. A Small Craft Advisory for Hazardous Seas is issued for seas 10 feet or greater.

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 customer needs, and should be no lower than 8 feet.

Pacific (HI, Guam, etc) - Sustained winds: northwest through east/southeast winds of 25 to33 knots for the coastal waters (30 to 33 knots for the channels between the islands); southeast through west winds of 20 to 33 knots for both coastal waters and channel winds. Swells: open ocean swells 10 feet and greater; swells 6 feet and greater with short periods (6 to 8 seconds); south swell 4 feet and greater with long periods (13 seconds and greater); north and northeast swells 5 feet and greater with long periods.

"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

BRISK WIND ADVISORY: A Small Craft Advisory issued for ice-covered waters.

GALE WARNING: A warning of sustained surface winds, or frequent gusts, in the range of 34-47 knots, either predicted or occurring, and not directly associated with a tropical cyclone.

STORM WARNING: A warning of sustained surface winds, or frequent gusts, in the range of 48-63 knots, either predicted or occurring, and not directly associated with a tropical cyclone.

HURRICANE FORCE WIND WARNING: A warning for sustained winds, or frequent gusts, of 64 knots or greater, either predicted or occurring, and not directly associated with a tropical cyclone.

TROPICAL STORM WARNING: A warning for sustained surface winds, associated with a tropical cyclone, within the range of 34-63 knots, expected in a specified coastal area within 24 hours.

HURRICANE WARNING: A warning for sustained surface winds of 64 knots or higher associated with a hurricane are expected in a specified coastal area within 24 hours or less. A hurricane or typhoon warning can remain in effect when dangerously high water or a combination of dangerously high water and exceptionally high waves continue even though winds may be less than hurricane force.

14. When the marine forecast says "seas 3-5 ft", what exactly does that mean?

Waves are measured from trough to crest. Seas are the combination of both locally generated wind waves and distantly generated swell waves. Specifically, seas may be derived using the following formula where S is the height of the swell waves and W is the height of the wind waves.
SEAS =

Seas and waves are expressed in the terms of the significant wave height, the mean or average height of the highest one third of all waves in a swell train or in a wave generating region. It approximates the value an experienced observer would report if visually estimating sea height. When expressed as a range (e.g. seas 3-5 ft), this indicates a degree of uncertainty in the forecast and/or expected changing conditions (not that all waves are between 3-5 ft). Generally, it is assumed that individual wave heights can be described using a Rayleigh distribution.

Example: Significant Wave Height = 10 ft
   1 in 10 waves will be larger than 11 ft
   1 in 100 waves will be larger than 16 ft
   1 in 1000 waves will larger than 19 ft
   There are occasional reports of "rogue" waves of an even greater ratio

Therefore, assuming a wave period of 8 seconds, for a significant wave height of 10 feet, a wave 19 feet or higher will occur every 8,000 seconds (2.2 hours).

15. Your marine forecast for my area was way off last weekend. What happened?

Weather forecasting is not a perfect science and conditions can change rapidly and unexpectedly. Always make certain you have the latest forecast and keep abreast of weather warnings via NOAA Weather Radio and other means. Most marine forecasts are updated every six hours and as conditions warrant.

Marine forecasting is made much more difficult than forecasting ashore due to a lack of available observations. Observations are required for NWS computer forecast models and by the forecaster to provide value-added decision making to the computer model output. Observations also serve to alert the forecaster when NWS forecasts do not agree the actual conditions and therefore, a problem exists in the current forecast process. Whereas 1000's of observations might be available for your local land forecast, only one or two observations might be available for the local marine forecast. NWS is continually working to expand its network of buoy and C-MAN stations, and volunteer observers.

The conditions in your location can be different than the general marine forecast due to local effects. For example, a strong land breeze might serve to flatten the waves immediately along the coast. A strong current, such as around a jetty can increase wave heights.

Be aware that wave forecasts are an average. The height of some individual waves can be expected to be as much as two times greater. Reports of "rogue" waves of even greater heights are not uncommon. See FAQ question #14.

16. I know marine observations are critical to your forecast process. How may I participate in one of your voluntary observing programs?

See Voluntary Marine Observation Programs

17. How do I convert knots(kt) to mph?

Some common unit conversions for mariners:

   1 knot(kt) = 1.15 mph = .51 meters/sec
   1 nautical mile (nm)= 1.15 statute miles = 1852 meters
   1 millibar (mb) mercury = .02953 inches mercury
   Fahrenheiht = 1.8*(Celsius) + 32
   1 fathom = 6 feet