The first, and most important source of weather information to me is my calendar. The southern tropical cyclone season is officially from the beginning of November to the end of April. The northern tropical hurricane season is the flip-side of the year. Simply put, if you are in areas prone to cyclones/hurricanes, its best to avoid the high risk times of the year. Look at the calendar and head north or south as the case may be, to avoid that hurricane, or in the case of the Caribbean this year, THREE!
That said, even when we are cruising on the right side of the calendar, it always important to be aware of weather systems that may affect our travel plans, comfort and safety.
Over the years, I’ve found that in a given cruising area, there are usually numerous good sources of weather information, although they tend to vary from area to area.
On the west coast of Mexico, for example, when I was cruising there in the late ‘90’s, our best and most reliable source of weather was a Ham broadcast called the Chubasco Net. A guy named Tom gathered weather information from various sources each day and then talked to the cruisers on a ham rig from his car while commuting to work in Southern California. He was usually spot-on in an area that was usually devoid of much good weather information.
The Internet has made a large body of weather information available to sailors almost anywhere on the planet. The equipment necessary to download grib files, buoy reports and weather fax has come into reach of most cruisers. This information is invaluable for passage planning and severe weather avoidance. All this combined with local and regional broadcasts (when available) can give the sailor a pretty good picture of the situation.
Generally speaking, when I’m planning a passage I do the following:
Consult pilot charts and Jimmy Cornell’s “World Cruising Routes” to determine the best time of the year to make the desired passage.
Turn on the weather fax a couple of weeks in advance to gain an understanding of the timing and movement of the local weather patterns. I tune into local fax broadcasts as well as ones well west of the area I’m in. In the South Pacific, for example, I look at maps from both Wellington, New Zealand and Melbourne, Australia to see what’s coming across the Tasman Sea from Oz.
Turn on the Sky Eye and compare the satellite photos to the weather faxes. Faxes are just educated guesses of weather sytems, but the camera doesn’t lie.
I talk to local sailors to learn from their experiences. In New Zealand, for example, I learned to leave just after a frontal passage on a southwesterly change. This strategy can usually get you up to the trade wind belt before the next system hits.
If possible, I use the services of a local weather router, like New Zealand Met Service’s Bob McDavitt for the South Pacific region. I find this is usually money (NZ $60) well spent, and there’s usually a group of cruisers willing to share the cost.
I download grib files for the passage area to see what the predicted winds will be along our course line and adjust my route accordingly to take advantage of the yacht’s best point of sail and wind shifts.
I listen in to the local VHF/SSB/Ham/AM/FM radio weather broadcasts.
Personal observation: sky, wind direction/speed and barometer.
When I’m on passage, I update the information as often as possible from all available sources and adjust the route plan accordingly. In the South Pacific, I usually check in daily with Des on Russell Radio to get his read on the weather along my route and to listen to what other passage makers in the vicinity are experiencing.
Once I’ve reached my destined cruising ground, I do the following:
Check the cruising guides for the best local sources of weather information. There are usually some combination of local VHF, SSB/Ham, AM/FM, TV broadcasts available. Here in Australia, the local Coast Guard stations broadcast good weather information to mariners regularly on VHF and SSB.
Ask the locals for the best sources of weather information.
Tune in to the local cruiser’s nets and listen to any weather information offered.
Evaluate all the sources to see who gets it right most often.
Keep the weather fax on and watch the weather patterns.
Keep an eye on the sky, wind direction/speed and barometer.
Move with the favorable weather patterns.