Bright Sparks 427 - Weather to Sail?

Our La Niña summer has had me continually studying the weather apps on my smartphone for the last few months and I’ve given up counting the number of cancelled sailing trips. So, sitting in the Coffs Harbour Yacht Club bar the other month, waiting for yet another blow to pass through got me thinking about weather services; or more specifically the devices to receive them on.

Wireless (Wi-Fi) services can also be used on the coast — I’ve used them successfully during several Tasmanian Three Peak’s Races — by attaching a Wi-Fi USB key to the laptop. For inshore sailing it can generally work in populated areas, so ideal for quickly downloading the latest GRIB file onto your passage-plan software or charts. The popular Navionics smartphone charts do this at the touch of button. By the way, Navionics has recently announced a High Definition version ($45.99 from the iTunes store) of this software to take advantage of the iPad3’s new high-resolution screen.

SMARTANEMOMETER
Another piece of interesting software is the Wind Meter, a real-time anemometer app. I use this when yacht testing, deciding when to change a headsail or just checking conditions. It works by measuring the pressure across the smartphone’s microphone. A warning though, it’s essential to calibrate it against an anemometer first and also use the MIC sensitivity slider to match your phone’s capabilities. It’s available from the Android Store on your phone and well worth the $3.99.

Back at Coffs Harbour, after reluctantly leaving the yacht club, sleeping off the effects of a few schooners and heading out in calmer conditions, my Telstra phone reception promptly disappeared, so it was time for traditional marine comms — the VHF. As we sailed south it was comforting to call in with the VHF toH coastal volunteer stations for a position report and weather check. Nowadays, for most parts of our coast they are the only source of regular VHF forecasts. Reception of course varied from good to none at all, so for bluewater sailors a HF radio remains essential.

High Frequency (HF) radio is the choice of offshore sailors. For racers competing in Category One events it is compulsory and for good reason since HF has a much longer range than VHF. They can also receive automated broadcasts from BOM. These broadcasts are currently sent by two stations in Australia — VMW at Willuna in WA and VMC in Charleville, QLD.

SOURCING SATELLITES
Satellite services are increasingly being used by smaller craft as the handsets become cheaper — for instance the vast majority of last year’s ARC fleet used Iridium. But competitor Inmarsat’s Isatphone Pro is about the cheapest handset on the market and now has basic (and slow) 20kbps data capabilities. This unit also comes with Bluetooth for hands-free use.

Once hooked-up via satellite, popular email providers to look for include Mailasail, Sailmail and Skyfile. It also gives you access to automatic downloads via RSS (Really Simple Syndication) feeds. RSS is a global standard of data communication used by millions of people for automatic downloads of favourite shows, news items and of course weather data. It’s inbuilt into the iPhone and most smartphones, or simply download an app. BOM supports RSS for weather alerts, a very useful service (log on www.bom.gov.au/rss).

Once you have data or Internet access a vast wealth of weather information is available for download in the non-proprietary GRIB format. The GRIB acronym refers to Grid In Binary, a data file format used for generating gridded meteorological data and is maintained by the World Meteorological Organization. For basic wind direction information this data, technically known as GFS files, are small and sometimes less than say 100kilobytes, so can be easily downloaded via a satellite phone or Sailmail SSB HF radio link while at sea and overlaid onto chartplotting software.

GFS stands for Global Forecast System and is a worldwide weather-prediction model run by the American NOAA/NWS and generates four updates per day. The data is available from various sources, such as www.grib.us which allows completely free global downloads and even includes a software package to display this info. More typically, the GRIBs are loaded into navigation software — if you’re a racer it might be to complex packages like Deckman or Expedition — but for general boaters it would be your chartplotter software.

MORE MOB
Finally, further to last month’s column on man-overboard devices I bumped into Steve Mullin from ACR who showed me the latest version of their ResQLink Plus personal locator beacon (PLB). As you can see from the picture hereabouts it now comes with inbuilt buoyancy yet remains about the smallest unit on the market so fits nicely into oilskin pockets. It’s on special at the moment for $399 with a free ACR strobe light (see www.acrelectronics.com).

Photo: With a steadily expanding supply of electronic weather sources, there is no excuse for not being prepared for dangerous weather events such as this tropical storm approaching the Singapore Straits.

This new Sydney Hobart raceboat has all the essential comms — Icom HF radio (top of picture), VHF, B&G Deckman for GRIB plotting and laptop for secondary charting and data downloads.

The Icom IC M80IE is an Australian approved HF radio and sells for $4299 from Aquatronics.
Inmarsat’s Isatphone Pro now has 20kbps data capabilities —just enough to download a 100kb GRIB file.

The Wind Meter app gives real-time measurements, after it’s been carefully calibrated.
I bookmark the www.seabreeze.com.au website into my smartphone for quick weather checks.

Navionics smartphone chart with wind option enabled.

ResQLink Plus personal locator beacon (PLB) now has inbuilt buoyancy (RRP $399).

From Trade-a-Boat Issue 427, May-June, 2012. Photos by Kevin Green; Icom.