Running from weather & the grib files shine

We waited late enough in the season that rather than enjoying a brisk NW to W wind at our backs down the Strait of Juan de Fuca, we retreated from the West Coast of Vancouver Island in light air between low pressure systems.

 

We saw this weather system approaching via grib files dowloaded on our SSB radio/pactor modem. Our position is marked by the green boat. For those not familiar with grib files, the wind arrows have a long bar for every 10 knots of wind so an arrow with three long bars and a half bar means a forecast of sustained 35 knot winds (gusts are extra). Also you can look at how close the lines around the low or high are together – the closer the bars, the higher the winds. At this point the system was far enough away that the local weather 5 day forecast was still showing light winds and with that information only we would not have left Barkley Sound. Based on the grib, we decided that it was a good time to start moving towards the inside of the island. The contrast between the 5 day forecast and the grib really showed us the advantage of being able to see what is forming.

low

 

By the next day, the grib file was showing the system intensifying before reaching shore.  Notice the 40 and 45 knot winds?

low2

 

By the time the low hit shore the forecast was for 50+ knot winds on the North of Vancouver Island and 40+ knot winds where we had just been. For context, 64 knots starts being called a hurricane.

 

We would have been fine. We would have ducked into a really great anchorage somewhere and had a rough few days. Experiencing those winds at anchor is sure to happen at some point on our trip. However, it was a lot nicer to not beat up ourselves or the boat and instead be watching sunsets and orcas.

 

Thank you to our SSB, our modem, and the people who post their hard earned knowledge on the sailing forums from which I learned and helped our installation go quickly, relatively painlessly, and work on the first attempt.

2 comments:

  1. 50 knots would = more suck than fun thus blowing your equation. Good call on moving inside!

    ReplyDelete