Arb
New Member
If you haven't seen it before, you all might enjoy Earth wind map which is introduced at The Register.
Earth wind map
- Thread starter Arb
- Start date
keithgdg
Well-Known Member
I get mine from passage weather.com. It gives wave height and pressure too.
Dave100456
Well-Known Member
funk-an-bord.de
Active Member
Its realy nice.
Fine for a general overview.
Thank you.
Wilhelm
Fine for a general overview.
Thank you.
Wilhelm
oldvarnish
Well-Known Member
Worth noting that this is not a representation of the actual wind, but is based on the output from the American GFS forecasting model.
franksingleton
Well-Known Member
Correct. It is, essentially the same as any other GFS display - XCWeather, Windguru. Passageweather, Ugrib, zyGrib, various apps etc, etc.
I doubt that it is any more use, probably less in view of the download size. Its main attraction to me is that it is a reminder of how complex the atmosphere is, even when so crudely modelled using computers whose power is miniscule compared to the atmosphere. It does show the whole globe in a way that no other display does (as far as I know.) In that way, it is unique.
A great teaching tool
tri39
Well-Known Member
I've been checking it for a NARC boat. It certainly clearly shows the low that's just formed in the trade wind belt!! And has also been demonstrating how fresh the trades have been recently. But not of course the very trying strong northerly cross swell, altho that hasn't showed up on the NOAA wind/wave faxes either.
franksingleton
Well-Known Member
Not surprising since they are the same data. I think that you will get a clearer display using zyGrib, UGrib, or any of the GRIB apps and with a smaller download because you can select the area of interest
tri39
Well-Known Member
Frank, can those Grib files show swell from two directions at once?
I have got ZyGrib to work on my iMac, but there's no wave info atm!
In fact the NOAA Opc wave period fcst/direction does show the "dominant' northerly swell.
But the problem for yachts is it's interaction with the following trade wind generated sea.
My correspondent reports alarming confluences!!
I have got ZyGrib to work on my iMac, but there's no wave info atm!
In fact the NOAA Opc wave period fcst/direction does show the "dominant' northerly swell.
But the problem for yachts is it's interaction with the following trade wind generated sea.
My correspondent reports alarming confluences!!
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franksingleton
Well-Known Member
I know of no GRIB service that provides such data. I do not now if any wave models produce forecasts of more than one swell train. It should be possible.
As far as I can see, the output in GRIB and other formats eg http://www.surfguru.com/florida-swell-forecast-wave-model i. is usually a combined swell and wind wave height and mean direction. Not very helpfully, that seems largely to be somewhere near the wind wave direction.
I have zyGrib on my Windows computer. I am surprised that you cannot get waves/swell forecasts. zyGrib has a MacOSX version.
Roberto
Well-Known Member
Hi David,
zygrib can download data from the WW3 model, they show both swell and wind waves (height and period).
After having selected the area, in the "Grib download" window there is the possibility to check some boxes with sea state data (sig wave, swell, etc).
The graphical interface only shows one set of arrows at a time, but if you look at the window on the side while hovering with the pointer over the grid points, it will show you the computed data.
In this example, (sorry the screen copy does not indicate the position of the arrow pointer), 5m swell from 238° with a period of 11s, combined with wind waves 1.34m high, 79° and 5s period.
Where are the seasickness pills
zygrib can download data from the WW3 model, they show both swell and wind waves (height and period).
After having selected the area, in the "Grib download" window there is the possibility to check some boxes with sea state data (sig wave, swell, etc).
The graphical interface only shows one set of arrows at a time, but if you look at the window on the side while hovering with the pointer over the grid points, it will show you the computed data.
In this example, (sorry the screen copy does not indicate the position of the arrow pointer), 5m swell from 238° with a period of 11s, combined with wind waves 1.34m high, 79° and 5s period.
Where are the seasickness pills
RobbieW
Well-Known Member
Fascinating what you can find once you start seriously playing with the buttons! Adding all that wave data does seem to add 40-50% to the file size however, so wouldnt want to be doing that too often using SSB on a crossing 