The Iridium 9555 is a great phone for use while sailing. It does have data capabilities, so you can use it as a modem with a laptop and get on the internet – but data speeds are verrrrrrryyyyyyy slow!

If you’re at sea, you’ll know how critical it is to have weather data. Luckily there is software available to allow you to get this info, even over low bandwidth internet connections like Iridum.

Basically, you need to use GRIB files to get the weather data. These files contain information which tells the map software where to put weather data on the map – rather than actually sending maps themselves (which would be large files). The files can be optimized so they are really small (100KB ish), so are ideal for downloading via an Iridium satellite phone.

There is free software you can use to download grib files. A couple we have tried are PredictWind and zyGrib. You can test these over a normal internet connection before trying our with your satellite phone, so you can experiment with the settings to get the grib size as small as possible.

Note: we don’t provide technical support for data usage or using grib software.