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CRC1965
08-12-2015, 05:02 PM
The predict wind software and the iridium go (satellite) device seems to offer a quick/light/albeit expensive way to get GRIB files offshore. My understanding was that this would "not" be ok for the LongPac....from what I can tell Grib Files are downloaded......is there a reason to believe this would/or would not be allowed for the TransPac?

Thanks,
Chris

Harrier
08-12-2015, 06:35 PM
I can certainly see nothing different from this in comparison with the weather fax pictures I get transmitted from Point Reyes. Or the grib files which are available via sat phones. As long as its not "routing" info and is available to all...should be OK.

CRC1965
08-12-2015, 08:43 PM
Thanks......If I then use software on the GRIB file once it is downloaded is that ok?
Is the "issue" just you can't have routing work done externally to the boat and then download?

Harrier
08-13-2015, 07:11 AM
Let one of the Bay area gurus answer that one. Sounds OK to me. I wasn't aware that the items you mentioned were taboo for the Long Pac. I'll be watching for the answer myself. Bob, are you lurking...????

DaveH
08-13-2015, 08:35 AM
My understanding is probably imperfect, as usual.

Here is the text of the pertinent rule; from section 11 [outside assistance] clipped from the 2014 SHTP Racing Rules and Conditions:

11.02 During the Race, no yacht may receive private or publicly available internet-distributed information regarding weather, currents, course routing or other tactical advice, with the following specific exceptions:
[a] Receipt of publicly available radio weather broadcasts.
[b] Diagrams commonly referred to as “weatherfax” generated by the U.S. National Oceanographic and Atmospheric Administration, or corresponding agencies of other countries.
[c] Communication on open radio channels [without encryption] with other competitors, which may consist of information such as current position, weather and sea conditions.
[d] Solicitation and receipt of information solely about the repair of any equipment on board, but not including routing advice.
[e] Weather data commonly referred to as GRIB files, derived from weather models operated by the U.S. National Oceanographic and Atmospheric Administration.
[f] The information about each yacht listed in RRC Rule 6.02 (but no other competitor data).

As I understand the rule, Gribs and weather faxes are allowed, but only from NOAA or other public agencies [eg the European or Canadian Weather bureau models] and that they are not manipulated by another model.
I think that there are likely 2 issues with Predict Wind.
1st, as Chris alludes to, it is a subscription service; parts of it are available to the public, but many parts are not unless you pay for them. Per their price list, the "free" gribs available offshore are 50km resolution. They have available 8km and 1km, but at a very steep premium.
2nd, and more important, their big selling point is that their model is better than anyone else's... and the GRIBS that are downloadable from them are from their proprietary model, not the raw data from NOAA's models.
That is why they would not be allowed; as I read the rule they violate 11.02e

you can get GRIBS from NOAA with the irdium GO... I did before the longpac to test the system; I used my saildocs account [sailmail]; basically the same procedure as with an SSB, but faster.
And yes, it is then completely allowable to pull them into expedition or other routing software to your hearts content.

my .02

DH

svShearwater
08-13-2015, 03:34 PM
Chris, I would wonder why you would want to use Predictwind just for Gribs? You can get GRIBs and wx charts and satellite images from Saildocs with any Iridium connection. Keep in mind that due to size of files and the time/cost of the download you will want to change to area of interest as you get closer to Hawaii.

Has anyone tried the new 0.25 degree GFS Gribs. That would make a BIG file if you wanted Cali to Hawaii over a number of days, for routing. Probably not practical. A blend of some sort might be an option. I feel like we might have started with 1 degree resolution and switched to 0.5 as we got closer.

Perhaps Predictwind does file compression that is a benefit over Saildocs?