Weather call

31464 03d1

Planning a daysail? Your go/no-go decision will usually include an appraisal of the local weather conditions, including the area just outside the harbor and along the adjacent coast. Planning a longer voyage in U.S. waters or one that begins or ends in U.S. waters? You will want to take a close look at the present and forecast weather along the route. Today we can obtain an amazing amount of high-quality weather information from the National Oceanic and Atmospheric Administration (NOAA) Web site. However you don’t have to use a computer to access the information that is often of greatest interest — current conditions at nearby locations. NOAA Weather radio’s VHF/FM broadcast system does an excellent job broadcasting current and forecast weather. In addition, NOAA and the FAA have made it possible for you to listen to up-to-the minute reports of conditions at hundreds of specific and often very useful sites by using your cellular telephone.

The NWS Web site
First, a look at what is on the Web site: The initial page of the National Weather Service Marine Forecasts site ( presents an array of more than 30 products. When on line the sites of greatest interest will likely include those under “Warnings” and those listed under “Observations.” There is a wealth of information available under the “Forecasts” heading. Selecting the Marine Forecasts site ( accesses an extensive list of resources under the general heading “Items of Interest to Mariners.” A mouse click on “Observations” opens a list that begins with two references, “Buoy, C-MAN (Coastal-Marine Automated Network), Ship and Drifting Buoy Observations” and “PORTS.” The information contained in these resources can be viewed on line and in addition virtually all of the information they contain can be accessed with a telephone.

Clicking on “Buoy, C-MAN, Ship and Drifting Buoy Observations” presents a map-based index to marine areas. For example, a mouse click on the area adjacent to the northeast U.S. coast opens an area map showing the location and identification of seven types of weather observation stations. Some coastal areas such as Narragansett Bay are densely populated with reporting stations like NOS Station NWPR1-8452660 Newport, R.I., and NDBC C-MAN station BUZM3 at the south end of Buzzards Bay (the location of the old Buzzards Bay tower). Click on a station to view the station’s identity, location, current meteorological information, including wind direction, speed, gust, atmospheric pressure, pressure tendency, air temperature, water temperature, data at 10-minute intervals for the past hour and a tabular listing for the previous 24 hours. A link provides access to a combined plot of wind speed, wind gust and air pressure. This information site also provides immediate access to area forecasts, SAR data, observations from nearby stations, regional HF radar surface current observations and the latest satellite wind map for the area.

Call a weather buoy
To access buoy data by phone, select the “Dial-A-Buoy” heading. The Dial-A-Buoy Data Center (888-701-8992) provides telephone access to all of the weather reports from the buoy and coastal weather stations operated by the National Data Buoy Center (NDBC) and numerous Integrated Ocean Observing System (IOSS) partners. The telephone-accessed computer system allows selection of a reporting station by its ID (look it up on line and save the reference number for later use) or by entering the buoy’s approximate latitude and longitude. An interactive voice menu allows selection of the desired reporting station or buoy. Both current observations and forecasts are delievered in a computer-generated voice. Mariners sailing in areas such as the Gulf of Mexico can also access weather information from sensors on oil platforms such as Station 42362 — Brutus — Green Canyon 158, a fixed drilling platform located at 27.8° N, 90.67° W.

The second listing under the “Observations” heading provides access to the Physical Oceanographic Real-Time System (PORTS). PORTS (Fig #5) is available in major ports including Chesapeake Bay, Delaware Bay, Narragansett Bay, Tampa Bay and others. This site displays the location of the sensing stations on a map, a satellite image and a hybrid overlay. Zooming in on the map presents an increasing list of stations. Clicking on a station displays the current and historical data in graphic form or on command, a tabular listing. The PORTS system can be contacted by telephone, providing real-time access to all of the data at each site including wind speed, direction, temperature, pressure and trend, etc.

Make use of aviation weather
Very useful weather information can also be obtained from the Automated Surface Observing System (ASOS) weather observation systems installed at airports near prime sailing areas. The information being gathered by these systems is broadcast to pilots on aircraft VHF frequencies and in addition can be accessed by telephone. The phone number for a particular airport’s ASOS can be obtained on line by entering the search term “asos phone number” followed by the three- or four-letter ICAO (International Civil Aviation Organization) airport identifier (the first letter for all US airports is “K”) in your browser. Alternatively, the phone number can be found by entering, selecting the Airports tab and entering the airport name or its ICAO identifier. In many instances the data provided will include the phone numbers and locations for all of the nearby ASOS-equipped airports. The automated ASOS voice report begins with the time of observation to the minute, wind direction (referenced to magnetic north) speed in knots, visibility in nautical miles, sky condition, surface temperature and dew point, barometer setting in inches of mercury and density altitude. Density altitude can be critical information for pilots, especially when operating at high-elevation airports. It may be of interest to sailors, particularly if sailing at a high elevation lake, since the force exerted by a given wind speed decreases as the density altitude increases. Higher than normal density altitude will also decrease the power available from boat engines operated on higher-elevation lakes.

The bottom line with regard to weather awareness is simple. Just about everything you might want to know about weather in U.S. waters is available, at no cost, from NOAA and the NWS, and once you have become familiar with the system you can access almost anything you may want or need using a cellular telephone.

By Ocean Navigator