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Full Version: How come weather on macenc never works?
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I've had this app for years - I've never yet gotten the weather feature to work - always says "Request for GRIB has failed".

Recently downloaded PolarView trial and tried out its GRIB feature and it works first time. So what is up with this feature on MacENC?
MacENC uses the free SailDocs service and relies on the OS X Mail application Preferences (Although any email client can be used to receive the GRIB) "GRIB Failed" message can usually be resolved by following these steps from the MacENC help ..

Request for GRIB fails on "Weather Menu"
- Make sure the Mac OS X Mail Application has at least one email account that can send and receive. The very first email address in the "Preferences" "Accounts" is used for the GRIB Request. Accounts may be dragged to change the order.
- Make sure the email account is not blocked in Keychain Access by following these steps:
* Launch KeyChain Access from the Applications / Utilities folder.
* In the search field in the upper right hand corner, enter the email address to find the password.
* [control] click on the password item.
* Select "Get Info".
* Select "Access Control" tab.
* Select "Allow all applications to access this item".
* Select "Save Changes".
* restart MacENCâ„¢.

MacENC uses mail protocol because many users are using XGate wireless email service with a Satellite phone at sea to request GRIB files.


That worked. Why do i have to do separate requests for winds and waves? Kinda inconvenient
My recollection is Wind uses the GFS model where Wave use WW3. GFS is on 1/2 degree resolution where WW3 is on 1 degree resolution. It may be SailDocs supports combining both types, but once again the thinking is to keep the files small for low speed sat phone transmission. The advantage of using an email connection is the support for mid file restart in the event the sat phone connection is lost mid transmission. Sat phone rates are falling, but still not cheap.
If you're re concerned about file size, why don't you have resolution as a variable like sailmail does? Offshore I often find that the finer resolution is overkill anyway, unless you're looking at a very small area.

Scot
Not a bad suggestion (Will be in next MacENC release), as we have area, days, interval as selectable to control the size.

The only issue would be if 1/2 degree was selected, not all areas and models offer 1/2 degree resolution.
Also the high resolution COAMPS wind/pressure model will be supported.
Perhaps the use of check boxes or menu items could be used to allow user control of data types requested, if indeed you are able to combine multiple types. That way, the user can not only control the resolution, but what types of data get sent. Just an idea.
No COAMPS available for West Europe?
"Surface Wind (COAMPS)" on the "Weather" "Request GRIB" will always be 0.2 degree intervals (High resolution), 48 hours on 6 hour intervals and limited to three regions: East-Pacific: 29n,60n,160w,114w / West-Altantic: 20n,55n,093w,055w / Cent-Am and Carib: 00n,32n,120w,060w.

COAMPS is a US Navy weather model..

http://www.nrlmry.navy.mil/coamps-web/web/home
GPSNavX Wrote:COAMPS is a US Navy weather model...
Yes, indeed, but I read on their website that :
Quote:The atmospheric components of COAMPS®, described below, are
used operationally by the U.S. Navy for short-term numerical weather prediction
for various regions around the world.
I was thinking that there were other "regions around the world"!
Possible, but MacENC uses the free SailDocs service which says:

COAMPS: This is a meso-scale (i.e. more detailed) regional model provided by the US Navy. Data is available for three regions: eastern Pacific, west Atlantic, and Carib/Central America. The syntax is the same as for a basic grib, except the request-code "coamps:" is used in place of "gfs:" or "grib:". Forecast data is available on a 0.2 x 0.2-deg grid at 6-hour intervals out to 48 hours (72 for west-Atlantic). For best results, use a grid of 0.2-deg or multiples of that to avoid interpolation.

MacENC uses SailDocs because of it's efficient email protocol which works well over satellite phones.