Friday, March 14, 2014

Predicting the weather

This one deserves its own post because it is so incredibly important to our life on the water. 

I never come away from a visit with Chuck in Anacortes without something useful and this trip was no different.  Chuck is the guy who owned Gray Hawk 3 owners back.  He’s the guy we called on to help us get her from Seattle to Anacortes in January 2011.  We never miss a chance for a visit on the way through Anacortes.

This trip I happened to ask him what he uses for weather information because that has been a huge issue for me.  There’s plenty of free weather sites that I use regularly.  Environment Canada has good short term information for the waters around Vancouver Island but there’s not a whole lot of depth to their site and certainly no charts that would help predict more than one or two days out. 

I regularly use GRIBs which, depending on who you consult, either stands for GRIdded Binary or General Regularly-distributed Information in Binary form. 


That’s a current GRIB for the northern Pacific or Gulf of Alaska for today.  As you can see, while it doesn’t explicitly show highs and lows, it is pretty easy to infer where they are.  In the northern hemisphere the winds blow counterclockwise around lows and clockwise around the highs.  So all you need to do is look which direction the little wind arrows are blowing and that will in turn tell you whether they are surrounding a high or a low.  GRIBs are designed for exchange of data with no interpretation so GRIB viewers can only interpret them based on rules.  For one or two day predictions that’s pretty well all you need anyway but I always felt like there might be more information I could use, if I could just find it.

Chuck told me that he subscribes to so I ponied up the 80 bux and got me a one year subscription.  There’s a lot of stuff on their website, most of which I don’t understand but I hope with time I will learn more. 


That’s the big picture – northern pacific – for today.  If you look closely you can see that we’re enjoying a bit of sunshine with crap on the mainland today.  Its windier today than this image would suggest – we’re in an area with wide isobars which should mean little or no wind but instead its blowing pretty good. 


And finally here’s a closer in view of our area which clearly shows the precipitation on the mainland.  Despite the fact that we’ve got sunshine today, rain is pretty well a given for winter boating – its wind we really want to avoid.  So I still need to learn more because these charts don’t agree with what’s going on outside my window.  Not that its any howling gale out there either – its maybe gusting to 20 with a steady 5 or 8 knots.  But these charts would suggest to me more like 0-5 knots.  0-5 knots is a nice cruise – gusting to 20 can put my crew in a bad mood.

No comments: