Weather info file

Weather info file

I know I keep saying we’re leaving, but the weather doesn’t seem to be cooperating, so we’ve postponed, twice. One of the things you have to get used to when living aboard is the fact that you can’t always just go where you want to right when you want to. Because you’re depending on the wind to get you where you want to go safely and, if at all possible, comfortably, having reliable connection to weather sources is key. Learning to read what you see comes next. Most boats use one or two of a number of tools to keep track of weather systems:

  • a weatherfax via SSB, which shows a regional forecast chart, including pressure ridges
  • GRIB files via an SSB radio service such as Airmail, which show predicted wind, waves and weather
  • a satellite phone with connection to a web-based weather service or fax
  • SSB radio weather broadcasts
  • or a weather routing service

Some folks go further and supplement that data by plotting weather experience data they hear from other boats on the cruising nets. Nets are radio meetups held daily at a designated time on a designated frequency to provide a check-in method and location record for boats making long passages. They’re a great resource and source for backup along the way. We’ve heard stories of boats passing everything from diesel cans to a boat with a downed mast to lending a blood pressure cuff to a man who was concerned about heart trouble, but turned out to have carpal tunnel! We checked in with the Pacific Puddle Jump and Barefoot nets on our Pacific passage.

For weather, we’ve been checking in with a website called while in port, and while at sea we use Sailmail’s weatherfax and weather file delivery service over SSB. Once the raw data files, or GRIB files, are delivered, it’s up to our skipper to figure out where the optimal winds and seas may be and navigate us around either the dead or the really rough spots.

If you are depending strongly on more accurate forecasts, for instance on an infamous passage, or if you are worried about your own proficiency, hiring a weather router like Bob McDavitt, who specializes in knowing where to go and when, can be a worthwhile expense. Routers contact you at a designated time by radio each day, or they may send you info prior to a passage depending on your arrangements. Weather routers aren’t right all the time, but they are a good resource to compare your own conclusions until you’re comfortable that you know enough to stay on track.

PassageWeather and the GRIBs all agree that the wind will be pretty light and seas kind of sloppy the next day or so, so we hope to motor around Nuku Hiva to Anaho anchorage today, then on to the Tuamotus sometime Thursday.

Wish us fair winds!