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+--- Thread: 500mb Grib Winds available (/thread-269.html)
500mb Grib Winds available - jagasail - January 20, 2007
Thought I had another thread on this but couldn't find it. Anyway, Saildocs just made 500mb wind available in their grib files. The parameter is:
WIND500
I tried viewing it in GPSNavX combined with the 500mb heights, and it worked great. However, the winds do not appear in the current version of MacENC.
A great weather tool.
Scot
- GPSNavX - January 20, 2007
Great, we will add that to the 500mb Height GRIB request. Also will allow MacENC to plot both the wind speed/direction and the pressure for 500mb Height.
- jagasail - January 20, 2007
Thanks; a great piece of software just gets better and better
~~_/)~~
Why 500mb and not 500 hPa? - cyberhusky - January 23, 2007
I thought hPA (hectoPascal) is the standard international unit for selecting weather data.
So why the millibar (mb) unit? In Europe it isn't used anymore.
Or am I wrong here?
Regards,
Manou
- cyberhusky - January 23, 2007
Oh I forgot to write: I know that 1hPA = 1 mb.
But the 500mb Wind GRIB file I tried yesterday gave me very high numbers: 5675 5786 etc. or low numbers if I suppose it this way 567.5 578.6 etc.
- jagasail - January 23, 2007
500mb charts work a little differently than surface charts. The contours on a 500 chart are actually heights at which the pressure is 500mb, so what you're seeing, for example, is 5675 meters elevation. However, in a practical sense they can be read like a surface chart.
Steve Dashew's Weather Handbook has a very extensive discussion of 500mb charts.
Scot