Expedition Navigation Software / Ensemble routing function "no wind" error

**Posted by Edward C-H** 8/02/2025 9:38 pm

I was recently trying to create an optimised route that extended beyond the area covered by the Access-Sydney grib file. This generated a "no wind" error when using the Ensemble function. This was despite having the Access-Brisbane grib file selected as file that the Ensemble function could use. The second file covering the area north of the Access-Sydney file that the route was to pass through.

Was this error to be expected or should the Ensemble function be able to pick up that there's a valid grib file available to use for the northern area not covered by the first grib file?

**Posted by Nick** 8/02/2025 11:55 pm

Yes, the different Access models are treated as different models in Ensemble routing.

**Posted by Edward C-H** 8/03/2025 3:33 am

Thanks Nick, given the limited area covered by the Access files it would be wonderful to have a way to concatenate the files for different areas. I assume that’s currently not possible in Expedition?

Alternatively, generating a route to the boundary of the grb file would at least allow comparisons to be made between different grb files for the period covered by the Access file.

I have tried the standard Linux cat function with the two files covering the same time period but does seem to work.

**Posted by Nick** 8/03/2025 1:07 pm

That won't work as the data is coded as different processes.

Just do routing not as ensemble and Exp will merge the data.

**Posted by sparky** 8/04/2025 7:45 am

I was wondering if it would be possible to build an ensemble grouping option...
A way to run Arome, Arpege, ECMW - UM UK, UM Global, ECMWF - NAM, GFS - WRF, UM Global, ECMWF... etc...

RIght now to do this you have to run the routes manually with those models loaded. Unload, load new ones -- rerun.

I spent a lot of time during the fastnet doing this to try to figure out what the French and UK models were showing and which one was better matching the current conditions on Windicator and our instrumenets.

**Posted by Nick** 8/04/2025 12:42 pm

I was thinking about this yesterday. I can think of several cases.

- Apege/Arome
- Access G and C areas
- ECMWF and the various Harmonie models
- GDPS/RDPS
- GFS/RAP/HRRR
- GFS/WRF
- UM-Global/UKV

It would mostly work just by having an option to group by originating centre. The only case that wouldn't work for is EC and the Harmonies.

I am fairly busy with a multi-month Exp project at present though.

**Posted by sparky** 8/04/2025 1:53 pm

I'd be happy for it just to be on the list.

**Posted by Nick** 8/05/2025 12:55 pm

I thought about this yesterday and almost decided on an option to use all data from the originating centre (for example, Arpege/Arome).

However, this idea would break EC AIFS/HRES.

So I am not sure how to do it yet that will keep the UI simple.