Features May 1, 2004 Issue

Headings: Get a GRIB on the Weather

The Weather Channel Marine and XM WX Satellite Weather offer on-board solutions to satellite weather that are pricy, but simpler and more familiar-looking than older systems.

Sailors are preoccupied with weather. It controls when we sail and where we sail. It influences our anxiety level. Access to weather information is a major concern for all sailors, whether sailing coastwise or offshore. 

Even a clear weatherfax map—this one received via SSB during Calypso's circumnavigation—requires skill to interpret. The newer satellite-based images available through proprietary systems will be familiar to anyone who watches the weather on TV.

Ashore, we tune our televisions to The Weather Channel, or log onto the Internet to see what's happening. There's a good chance you even have a VHF radio at home to check the local NOAA weather.

Once you step aboard the boat and drop the mooring, however, things change. Unless you have satellite television aboard, The Weather Channel is a fond memory, and (lacking an unlimited budget) high-speed Internet access is just wishful thinking.

For coastal sailing, most of us depend on the familiar NOAA VHF weather to provide local information. But what if you want more information than NOAA weather radio offers? And what do you do for weather once you're so far offshore that the VHF signal vanishes? The answer depends on where you sail, and the depth of your pockets.

Over the next few months, we're going to look at a variety of methods sailors can use today to augment their weather knowledge and lessen weather-related anxiety. None of these solutions is cost-free, and some can be downright expensive. All require a certain investment in hardware and software. You, the sailor, will also have to invest time in learning exactly how these systems work if you want to get the most out of them.

Where We Are
For the last 20 years or so, offshore mariners have largely depended on weatherfaxes broadcast via SSB radio as a prime source of weather information. High seas voice and text forecasts—also broadcast via high frequency radio—provide analysis of weather charts. Receiving and interpreting weatherfaxes requires a reasonable knowledge of the way weather works, a significant investment in both hardware and software, and patience.

We have spent hours at the nav station in the middle of oceans around the world, fine-tuning the radio, switching between frequencies, trying desperately to generate a usable image on the computer from a static-filled signal bouncing off the atmosphere. It can be hard work that adds substantially to your stress level, particularly when the fax image degenerates to an unreadable gray just when it's transmitting the weather for your little part of the ocean. Miss it, and it may be 12 hours before you have another shot at capturing a chart.

For commercial mariners, traditional SSB-based weatherfaxes are becoming relics of another age. Satellite communications systems are the norm on everything from offshore fishing vessels to aircraft carriers. With today's large-scale, expensive systems comes a convenience that every weather-conscious sailor covets: high- speed data transfer, not only for e-mail-based communication—including the transfer of large graphic file attachments—but for direct access to the Internet and its Aladdin's cave of weather information.

We take this for granted at home. You can sit in your study in Oklahoma, enter www.metservice.co.nz in your Internet browser, and view surface analysis and prognosis charts for your armchair crossing of the Tasman Sea from New Zealand to Australia. Want to see when that spring gale in the central Aegean Sea is going to blow itself out? Go to http://forecast.uoa.gr/forecastnew.html. For the weather a little closer to home, entering https://www.nlmoc.navy.mil gets you into the wonderful world of the US Navy's meteorological branch, with much of the money invested and weather technology owned by the US military at your fingertips.

But again, for most sailors, it's back to the weather stone age once you drop the mooring and head outside the range of the VHF weather.

Slowly but surely—and on rare occasions, very quickly—sailors' access to more sophisticated weather information is becoming a reality.

There's good news and bad news here. First, we have yet to arrive at the time of low-cost, high-speed Internet access aboard your boat. If you're within cellular phone range, you can obviously interface your cell phone with your computer, just as you can at home. This is hardly new technology: we have been doing this aboard since the mid 1990s.

Generally speaking, however, the data transfer rate for the typical cellular connection is too slow for efficient searching of the Internet, with its data-intensive, graphics-rich content. Once you're beyond cellular range, the rules change again, unless spending money like a drunken sailor—a very rich drunken sailor—is your cup of tea.

In the May 15 issue, we'll look at one PS contributing editor's experience with the Globalstar satellite telephone service for verbal communication and limited data transfer. In a follow-up article later this year, we'll look at how the same system can be used for more intensive communication and Internet access for sophisticated weather routing for offshore sailing. When used in conjunction with weather services and websites specializing in compressed data files or GRIB (gridded binary data) files specially generated for transfer using slow-speed satellite phone technology, the Globalstar system is a powerful tool for sailors.

When we sailed around the world aboard Calypso beginning in the late 1990s, she was equipped with a mini-M satellite telephone. Transferring data at 2400 baud via mini-M, access to the Internet was totally impractical. For basic daily e-mail—and we mean really basic—our monthly telephone bills typically ran about $600. Even at that, you could forget about graphics.

Sending the text of a simple, four-page article from the boat in the middle of the Pacific via e-mail could cost $40 in airtime by the time you logged onto the system, transferred data, and logged off. The cost of sending a one-megabyte digital photograph was out of control. The simple act of downloading a half-dozen short e-mails and sending the same number took about seven minutes, eating up almost $15 of airtime.

Granted, if sending and receiving simple e-mails is your only goal, there are other options available today that trade low cost against a fair amount of inconvenience. In particular, SSB-based e-mail programs such as Sailmail, operated on a not-for-profit basis, offer access to weather information through the transfer of GRIB files or conventional text forecasts.

For once, the cruising sailor actually has access to better information than racing sailors. For example, the Newport-Bermuda Race—one of the sport's premier offshore racing events—limits the type of weather information than can be received by boats after the start of the race. While general use of the Internet is permitted, you may not receive weather information via e-mail, nor may you use restricted-access or password-protected Internet weather pages. Weather routing software companies comply with these rules by publishing re-formatted but unedited weather model predictions on their websites in the form of GRIB files. While anyone with Internet access can download these files, they can only effectively be processed onboard by proprietary software.

In a way, it's no different from accessing weatherfaxes on the SSB. Anyone can listen to the broadcasts, but unless you have the hardware and software to convert those electronic chirps into a graphic image, they're useless.

Requirements are even more stringent for the Volvo Ocean Race, an all-professional round-the- world race. While the boats will be equipped with high-speed Fleet 77 communications capabilities, designed for the transmission of on-board video to shore, the system may not be used for Internet access. Daily weather will be supplied by race organizers to all competitors via GRIB files, but strategic and tactical decisions must be made onboard, without outside assistance from weather routers or websites.

The intent of the organizers of both races is similar: make the sailors onboard determine the tactics, rather than relying on outside weather routers. It's not that different from saying you can't use your engine for propulsion during a race.

Cruising sailors are more fortunate. We can take weather information and advice from any source—and we do—and we can use our engines to get from point A to point B when the wind fails.

The lead article in our May 15 issue will tell of our experience in trying out some for-fee weather forecasting services for a passage from New England to Bermuda.

Near-Shore Solutions
What if you aren't heading across the ocean, but are out of VHF range? What do you do if you want more information than the local NOAA weather channel provides?

We recently looked at two new weather services that provide the type of augmented weather information we are used to with shore-based access both to cable TV and the Internet.

One of the most intriguing new weather services for boaters is The Weather Channel Marine. If you're already a Weather Channel junkie, this is a logical extension of the cable television service that you view every day.

To access The Weather Channel Marine, you need to buy a proprietary satellite receiver and antenna for $1,995, and subscribe to the service for a yearly fee of $695, or a seasonal fee—for those of us who can't sail year around—of $395. The antenna is virtually identical to many GPS antennas, and the receiver box is about the size of a thick novel.

Processing software is installed on your computer to complete the interface between the satellite and your boat. Virtually any modern (less than three-year-old) computer using Windows 98 or later Microsoft operating systems will be adequate for the job. A processor speed of 300 MHz or faster is required. Obviously, the bigger and better the screen, the better the graphical representation will be.

At this time, you can only buy the hardware from authorized dealers, who make their money on the hardware sale and the installation. The installation should actually be quite straightforward.

Weather Channel Marine supplies a wide variety of information, beginning with Weather Service International's (WSI) live NOWrad Doppler weather radar. If you've ever watched The Weather Channel, or your local weather on a broadcast channel, you have a pretty good idea of what this type of radar image looks like. The radar image is updated every five minutes, and can be animated to show the progress of weather systems.

An important advantage of this service is the ability to interface with charting software. The Doppler radar images can be animated, scaled, and overlaid on your chart plotter. At this time, this integration is only available for Maptech's innovative I3 touchscreen navigation system, as well as the new Raytheon H6 navigation, radar, and communication system. If The Weather Channel Marine proves popular, we expect that interface with other charting software will follow.

The advantages of direct interface with existing charting software are obvious. If you have watched Doppler radar images on television, you know they would be a perfect way to track the path of extreme weather such as thunderstorms and severe fronts. Imagine being able to overlay these images on your boats position, zooming in and out, and animating the movement of weather features over time.

This is a powerful tool for avoiding or preparing for extreme weather, such as fast-moving summer squalls and storms. If you navigate with conventional radar, you have probably developed an appreciation for its ability to detect and track nearby thunderstorms.

Using conventional on-board radar is a form of micro-tracking, since you can only see weather that is within range of your radar, and only if it contains a lot of precipitation. The Weather Channel's Doppler radar is a macro solution, allowing you to track features that may be hundreds of miles away, but which may have an impact on you hours or days from now.

If you fly your own plane, this will all sound familiar. Pilots, just like sailors, are obsessed with weather. Weather Services International, The Weather Channel's partner in The Weather Channel Marine project, provides similar services for pilots with their InFlight aviation weather. Using exactly the same technology, InFlight provides real-time Doppler weather images to pilots. Since the InFlight service is compatible with Garmin's AT multifunction avionics display, we expect to see expanding compatibility of the marine version with plotting systems as demand for the service increases.

You get more than Doppler radar images with The Weather Channel Marine. NOAA text forecasts are available, in an easy-to-use interface. The program allows you to click on the chart display for the current regional NOAA coastal and offshore forecasts for that zone. This is particularly useful for offshore sport and commercial fishermen, who often operate beyond the range of local VHF forecasts.

You can also get real-time marine buoy reports by clicking on the icon for any weather buoy. The location of these buoys is marked on the displayed chart.

For offshore fishermen and sailors concerned with the Gulf Stream and other currents, high-resolution sea surface temperature graphics highlight these features.

Coverage of The Weather Channel Marine extends about 150 to 200 miles offshore—far enough for any coastal or near-shore sailing. Expansion to the southern Caribbean and the north coast of South America is planned in the future.

This is a flat-rate, unlimited use system. Once you buy the equipment and pay the annual subscription fee, you are free to access The Weather Channel Marine as much or as little as you want without additional charges. There are no add-on premium products to raise the price.

The on-screen presentation varies with the type of display used. With a conventional computer screen, the presentation is oriented as a menu-driven desktop, and is easy to operate with your computer's pointing device. If used in conjunction with Maptech's I3 system, the desktop presentation is modified to incorporate the Maptech touchscreen. Both presentations are intuitive and easy to follow.

For use in the cockpit, the Maptech system—which we'll look at in the future—offers obvious advantages, since it's waterproof and requires no pointing device other than your finger. If you already have a computer at the nav station, you will find The Weather Channel software as easy to use as charting software.

You can find out more about The Weather Channel Marine at www.weather.com/marine.

XM WX Radio
XM WX Satellite Weather is direct competition for The Weather Channel Marine. The XM service uses XM satellite radio's two geostationary satellites—known as Rock and Roll—to broadcast proprietary marine weather to boats. Just as with The Weather Channel Marine, this is an extension of XM Satellite Radio weather services for aviation and land-based consumers, including emergency response agencies.

The onboard XM WX system consists of a compact antenna similar to a conventional GPS antenna, plus a small receiver/signal processor comparable in size to that of the Weather Channel receiver. Full-color mages are presented on the boat's computer screen.

Information is similar to that offered by the Weather Channel, including continuously updated Doppler radar images, buoy reports, sea state representation, and thermal images of bodies of water.

The desktop presentation of the control panel is intuitive, easily understood, and easily operated. A zooming feature allows you to begin with the default presentation of the entire United States, then zero in on an area with a radius of only .1 mile.

Cost of the XM WX system is $730 for the antenna and processor, plus a monthly service charge of about $50. No long-term subscription is required. For $930, you can get an upgraded system with a GPS interface, allowing your boat's position to be presented on the displayed map. We say "map" rather than chart, because the display is a fairly simple, undetailed geographical representation, rather than one containing the type of information you're familiar with on marine charts.

XM WX Satellite Weather is a product of Wx Worx. Meteorologist Bob Baron, whose Baron Services company has been delivering customized weather since 1990, created WX Worx in 2002 to provide mobile weather services.

The service footprint of XM WX Satellite Radio covers coastal waters of the US, plus the Great Lakes. More information is available at www.xmwxweather.com.

Conclusions
The information provided by either XM WX Satellite Weather or The Weather Channel Marine is far more detailed than what is provided through the conventional NOAA weather radio VHF system. Unlike VHF radio, which is basically a line-of-sight service, satellite broadcasts are available anywhere within view of the satellite.

You have to use the same common sense in choosing an antenna location for either of these systems that you would employ when installing a GPS antenna. An unimpeded view of the sky is essential for optimum performance.

We have only examined display versions of both of these systems, so our observations are based on limited hands-on experience at this time. We plan to do real-world testing in the near future.

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