Pressure Slope

[Bobson]

Could someone please explain the new ENV Canada pressure slope on the BWD Web Site..??

Also, what is the UTC time difference from us here on the West Coast..??

[JL]

Bobson...the pressure difference between 2 points approx. 60 naut.[6080 ft.] miles apart allows a reliable prediction of wind for our [georgia basin] area.....go to"www.weatheroffice.pyr.ec.gc.ca/marine/p ... ope_e.html" for a quote from 'the wind came all ways'...and a current pressure slope reading...utc time is universal coordinated time,a time standard that allows the world to sync. time...daylight saving time we are -7 hrs....the rest of the year -8...subtract this number from utc to see when reading was taken...for juan de fuca we prefer to use the difference between tattoosh & smith island[ but tattoosh has crashed] this # times 10 is a great predictor for race rocks, allowing us to plan trips to cook st., tugwell etc. good luck and be patient, after a while this won't seem like rocket science and will just be another tool on the rd. to windsurfing........jim

[bwd]

Excellent explanation Jim. I'll just add that you can buy the book "The wind came all ways" from most bookstores and it gives a great description of the different pressure slopes and wind directions etc. It is a good book for local conditions and talks about fog banks, SE'erlies, NW'erlies etc.

I added the link to the pressure slope and removed the real time Race Rocks link since it wasn't too reliable. Often I would check the real time race rocks link and in would give North at 3 knots when Race was west at 20. Hopefully it will be fixed. Note that the Pressure slope link is sometimes not updated and sometimes there is just the table with no picture of the pressure slope direction. It is way better than my simple model of (Tatoosh-Smith) x approx 10 as it gives a direction. I would look for a westerly or NW slope of at least 2, high 2's are great and above 3 really good for westerlies in the Strait. Also as Jim mentioned Tatoosh Island readings have been down since July 25 so that is why my pressure gradient plot has not been updated.

Lets hope the gale warning today comes through, dave

[jen-weather]

Many years, Env Can gives away the book at the Boat Show at BC place stadium. Free book, but it'll cost you admission to the show.

[nanmoo]

The local library won't even let you sign it out now. Have to read it there.

[JL]

Tatoosh Is. site is no longer available so we use Neah bay / Smith Island. www.bigwavedave.ca/RecentData/PressGrad_recent.htm Env. Canada no longer provides pressure slope data but you may be able to find 'The Wind Came All Ways By Owen S. Lange' in used book stores