Appendix II – Weather Information

The best way to survive a storm is to avoid it. We are fortunate that these days that is much easier than it was in the days of old - or even in the days of the early editions of the DDDB.

The two most notable developments are GPS, which tell you exactly where you are at any moment, and satellite phones.

The satellite phone, if you interface it with your laptop, allows you to receive GRIB weather files, and other weather information, either on demand or on a schedule. That means you can have up to date weather forecasts even in the middle of an ocean!

This can also be done using HF/SSB and a suitable pactor modem.  The catalogue function on Win Link 2000 has good weather information for just about anywhere you would want to sail.

Plus, of course, weather forecasting itself has come a long way.

Below we have listed some resources that may help you to plan your cruise, and keep updated during your passages. Don't wait until the day you depart on an ocean crossing to investigate these: test and make sure your weather information system is working reliably before you cast off!

National Hurricane Center – the horse’s mouth for hurricane and storm forecasts and advisories for both Atlantic and Pacific. Also some useful graphic tools showing predicted wind strength probabilities. The Tropical Weather Discussion and Offshore Waters Forecast are perhaps the most important on a daily basis, and are available as low-bandwidth text files making them suitable for satellite downloads. They can be found in the 'Text' section of the NHC Marine Forecasts page. Note that these are human generated forecasts, not just computer models as are the GRIB files. As such they are invaluable and FREE. :-)

Ocean Prediction Center – for cross Atlantic and Pacific weather charts and synopsis etc.

StormCarib: Caribbean Hurricane Network – Useful local reports from all the Caribbean Islands with and emphasis on forecasting and tracking tropical storms and hurricanes. Also has some very interesting archives on historical hurricane frequences and tracks.

Climatology of Global Ocean Winds – average historical winds for all the world’s oceans. Good for cruise planning.

Saildocs – receive free GRIB files by email, and use their free GRIB viewer, Viewfax . This is the service to use if you want to receive weather info through your satellite phone.

Zygrib, available free from  zygrib.org, is another GRIB viewer that will also automatically download GRIB files if you have an internet connection – or will read files you have downloaded separately or have received by email.

MailaSail offers a GRIB delivery service, and also provides good information on choosing a satellite phone and, most importantly, how to interface it with your laptop so as to receive emails (such as GRIB files) through your satellite connection. IMPORTANT: if you connect your laptop through a satellite connection you MUST turn off all the automated updates etc. that your laptop does in the background, otherwise your satellite connection will grind to a halt. Better still, use a dedicated laptop with a totally clean installation, just for your at-sea navigation etc.

Live Weather Reports. Another free service that will send you the latest weather and sea state reports from ships within 300 nm of your current position. Just send an email with your current position, and receive the weather report back.

PassageWeather.com also provides online grib display, plus wave heights and some other useful graphics.

Frank Singleton’s Weather Pages – Very informative. Frank is an ex UK Met office meteorologist and now a live-aboard cruiser. His site has loads of information about weather, how to read weather reports, what makes the weather etc, and sources from which to get reports and forecasts.

NAVTEX: for frequencies and schedules see Frank’s Navtex Schedules page and also WORLDWIDE LW Navtex Broadcasts

Weather Underground – whole host of global  information: weather reports, storm watches, tutorials, etc

Cruisers Forum has a thread devoted to marine forecasting. Very interesting.

Weather Routing Services

If you want more individualized weather advice, there are several companies that will, for a fee, give you weather routing advice specifically tailored to your own personal circumstances. These services are frequently used by racing yachts, but are equally suitable for cruisers. They will want to know your intended route and departure dates, the type of boat you have, and your weather tolerances (e.g. how much 'rough' weather are you happy to tolerate).

The companies listed below are only a small selection, and have not been tested by the authors.

Commanders Weather

Weather Routing International

Rich Shema -  The Weather Guy

Bob Jones - Ocean Marine Nav Inc

Bob Cook - Ocean-Pro Weather Services

WeatherWeb - UK based, but also provides bespoke forecasting for Atlantic crossings.

Chris Parker - Caribbean, Bahamas and East Coast of USA

NOTE: If you get yourself a satellite phone, pre-program into it the emergency phone numbers for the coast guard of your home country, and the countries nearest to you, plus any other emergency numbers that might be useful.

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Using Parachutes, Sea Anchors and Drogues to Cope with Heavy Weather – Over 130 Documented Case Histories