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Jeff Jeff is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 1,301
Default marine weather question

NE Sailboat wrote:
when I see a marine weather report, the wind direction is given. for
example: wind from the southwest at 10-15 knots.

is the wind direction based on the true compass direction or magnetic?

So,, wind from the southwest = wind from 225* true

And if along the coast of Maine this would mean = wind from 242* magnetic

Do I have this right?


The report always assumes True, not Magnetic. Since many of the
recipients of the reports are land based, and not using a magnetic
compass, the reports would make no sense if not True.

While the forecast may not always be accurate enough to make a
difference, it now possible to get realtime reports for stations. In
fact for several years I've been picking up report on my cell phone
that include wind speed and direction. I can stay connected much of
the time on my normal travel routes, so if I used a PC for navigation
(instead of my 'berry for quick updates) I might be getting reports like:

http://tidesandcurrents.noaa.gov/dat...20Observations