Iridium Wx:
This is an interest of mine and something I have done but am not fluent in so here is a summary from a friend with whom have did many miles offshore in N&S Atlantic back in 2007. He did Labrador, Greenland and then the NW passage last year. He has sailed about 50,000 offshore in the last 10 years. Iridium is his primary means of Wx (
http://www.issuma.com/rhudson/issumaboat...Issuma.htm )
The MacOS is a detail that adds a bit of complexity since there are still a few more WX tools in the MSwindows domain but that is changing fast, the trick is to just get an email link going as a way to get the data in the computer. I personally like ZyGRIB multi-platform program for GRIB viewing (
http://www.zygrib.org ).
Note: My friend was in the S Atlantic when he wrote this....
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Iridium Weather:
I have a pre-paid card for Iridium service with satellitephonestore.com (i think). I have a uuplus.net email account (it is not feasible to use iridium for email without a uuplus.net or similar account to help with compression/speedup and minimize $$$ bandwidth).
I use saildocs to send me grib files. I do not have a saildocs account or subscription. You can email query@saildocs.com with a body of:
send grib-info
for more details.
The grib files I am currently using are emailed to me daily. I receive these for (default) 10 days because I sent the following email to query@saildocs.com (subject is not necessary):
sub gfs:22S,35S,38W,55W|2,2|6,12,18,24,30,36,42,48,60,72,96,120,144,168|PRMSL,WIND
That gives me the GFS (as opposed to another model called NOGAPS) forecast for the area 22S to 35S, 38W to 55W, with pressure at sea level and wind speed/direction. If you send the above email with a "send" instead of "sub", then you will get that grib file just once, not daily. If you change the "sub" to "cancel" it will cancel that subscription.
You can append (no quotes) time=0700 days=5 to the command (on the same line) to receive it at 0700 UTC, and only for 5 days instead of the default 10 days if you wish. There are a bunch of other options, but changing the lat/long and the time and the number of days is about all I ever do.
Either via uuplus.net's WebFetch (part of their email program), or saildocs, I also get the GMDSS Metarea 5 and 6 forecasts daily. From saildocs, that would require an email of:
sub Met.5
sub Met.6n
From WebFetch, the configuration just requires the time to get it and the URLs:
http://weather.gmdss.org/navimail/GMDSS_...5_INMARSAT
http://weather.gmdss.org/navimail/GMDSS_...0_INMARSAT
If you're planning on doing this at sea, it would be worthwhile getting all the subscriptions setup soon and getting familiar with requesting and receiving the daily grib forecasts before getting the Iridium phone & uuplus account.
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