Weather Routing

[ALROCHARARI]

Originally Posted by wholybee

While you think every setting is the same, if the results are different then they almost certainly are not.

Can you post your boat.xml file(the one named for your boat), your WeatherRoutingConfiguration.xml file, your polar file, and the grib file, each from both the windows PC and the pi. I am sure you will find something is different between them. There are settings which if incorrect will cause odd routing like that.

My official thanks to wholybee and appologises to all!
I found the difference. My fault.

It was the flag to take the cyclons into account.

So I don't use it anymore.

Can somebody reproduce it?
If yes then it might still be a bug.
At least I don't succeed to understand what is the meaning of these lines.

Have a nice day.

[rgleason]

Alrocharchari

Are you saying that Post 2319 https://www.cruisersforum.com/forums...ml#post3700210


Is caused by turning on Cyclones? Are you turning them on in Climatology?



or are you Checking the "Avoid cyclone tracks within (1) month (0) days" which is in the ADVANCED TAB?
- IF this is true, then you must expect some strange tracks!!! This is a feature that could be very useful for some cruisers.

[ALROCHARARI]

Originally Posted by rgleason

Alrocharchari

Are you saying that Post 2319 https://www.cruisersforum.com/forums...ml#post3700210


Is caused by turning on Cyclones? Are you turning them on in Climatology?



or are you Checking the "Avoid cyclone tracks within (1) month (0) days" which is in the ADVANCED TAB?
- IF this is true, then you must expect some strange tracks!!! This is a feature that could be very useful for some cruisers.

I confirm it was "Avoid cyclone tracks within (1) month (0) days"
I don't understand the way this feature is working

[rgleason]

The computation will try to make a route that avoids those tracks.

[ALROCHARARI]

Originally Posted by rgleason

The computation will try to make a route that avoids those tracks.

So evident


Thanks a lot

[ALROCHARARI]

I'm now facing another issue which I hope is as easy to solve as the previous one.

I'm trying to make my routing as accurate as possible with the usage of currents.

I have harmonic currents but I'm not sure they are correct.
I think it's possible to have surface currents from grib data.

My main questions are:
- Is-it possible to use more than 1 grib file at a time?
- Are the surface currents added to harmonic currents in the weather routing calculations?
- How can I have the most accurate data along the "Route du Rhum" path?
- Where to download the surface currents data?

So far I never succeeded to have currents informations included into my weather routing calculations and the areas where I want to sail have very strong currents.

Your help would be appreaciated guys.

[rgleason]

The manual shows how to load/use two grib files at once, so you can load a grib file with ocean currents and use that by checking the use currents box.

Try this out on something simple.

You want the surface currents.

[ALROCHARARI]

Originally Posted by rgleason

The manual shows how to load/use two grib files at once, so you can load a grib file with ocean currents and use that by checking the use currents box.

Try this out on something simple.

You want the surface currents.

Perfect answer as usual. Thanks a lot SIR

[ALROCHARARI]

Question for people sailing using the Reeds Nautical Almanac (So sailing between Denmark & Gibraltar):

What is your best input for currents and tides informations?
Where do you take the data from?

Thanks in advance for your help.

[rgleason]

I am at my computer now so it is easier to get the the manual.

Open Two Grib Files

This won't help with Denmark & Gibraltar but it does do American Atlantic ocean currents RTOFS gribs based on HYCOM

https://polar.ncep.noaa.gov/ofs/download.shtml
https://polar.ncep.noaa.gov/global/

Gulf Stream https://polar.ncep.noaa.gov/global/fronts/

Luckgrib has a very useful reference for Current data sources here
https://luckgrib.com/models/rtofs_global/

OSCAR gribs for ocean current
average of the ocean currents over a 5 day period.
Luckgrib info on Oscar
3rd degree Jet Labs

Copernicus Data Model must have ocean current but I have not found it.
Oscar currents with velocity Youtube
There used to be a good website for downloading this. Seems to be missing.
Surface current velocity Hamburg Germany

European RTOFS
Using Luckgrib https://luckgrib.com/models/group/europe/

EuroGoos Global Real-Time Ocean Forecast System (RTOFS) https://eurogoos.eu/modelling_inventory/us-ioos-2/
(Can't find any data here.)


The more practical way of getting ocean current gribs.

Viewing Ocean Currents (RTOFS) in XYgrib
https://youtu.be/kxuVnyDI23Y
Predictwind summary HYCOM, Mercator, Ocean and tidal currents
XYgribs Opengribs website is very useful.
XYgrib Software github https://github.com/opengribs/XyGrib

https://openskiron.org/en/openwrf says it has Sea current velocity & direction
This seems to be the best way that I have found to get sea current in Europe.
https://openskiron.org/en/openwrf


Hope this helps. (of course you can select to get RTOFS in the Opencpn Grib settings.)


Grib_pi settings Request Button https://opencpn-manuals.github.io/ma...request_button


RTOFS gribs only contains current and water temperature data.


Note that ZYgrib program is the predecessor to XYgrib. This needs to be updated in the manual.

[Rasbats]

And this one:
Sailing Weather Online

Mike

[rgleason]

Originally Posted by Rasbats

And this one:
Sailing Weather Online

Mike

Thanks Mike. Very nice website!!!!

[te fenua]

Thank's for your work's,
In the listing of the routing weather prevision track it would be
interesting to have a column for the wind speed
and one for the force of the winds

[rgleason]

Originally Posted by te fenua

Thank's for your work's,
In the listing of the routing weather prevision track it would be
interesting to have a column for the wind speed
and one for the force of the winds

I think what you want is Grib_pi Weathertables, see the grib_pi manual
https://opencpn-manuals.github.io/ma...weather_tables

Check out grib weathertable "settings"
https://opencpn-manuals.github.io/ma...html#_settings

By moving your cursor to various route locations and stepping through the grib file time bar, you will see the parameters you want.

Also under WeatherRouting_pi View > Settings shows a number of parameters for the optimal route that can be selected to show under the routes configuration results at the right of the configuration window.

Also Don't forget about using View > Plot and selecting parameters from the 3 drop down selectors. The use the position arrow to view the changes along the optimal route if you have radio button "Current Route"


I have not written about these features in the manual BTW. Someone who has the inclination to complete this section would be contributing to the common effort.

[te fenua]

thank's for your quickly response but that i suggest is like the picture join to do as QTVLM or Avalon, the must will be to add also TWA and sail column's