On our 5-year circumnavigation of the Pacific Ocean, we used GRIB files (Gridded Binary data files) to read the weather.
They are computer-derived weather forecasts packed into a digital file. They are compressed versions of the weather data found on weather forecast websites, 1/2 to 1/3 of the size of the normal binary files. GRIB files can be quite large, so it is therefore necessary to specify an area of coordinates with an appropriate resolution to keep the files small, the transfer fast and the whole transaction not too costly.
When downloading GRIB files, you have the option to select extra parameters, such as Wind, Rain, Wave, Cloud, Temperature, Sea Surface Temperature and Current.
We download them using our SAT phone's data by way of saildocs. Documents are requested by sending an email to: email@example.com. Saildocs is an automated system and the format for an email grib request must be followed exactly. Follow this tutorial to find out how to write weather data requests.
After successfully downloading the GRIB file, we connect to the Iridium GO with our laptop or phone, and visualize them using the free version of PredictWind.