The Offshore App is designed for boats heading offshore with a need to download forecast GRIB files and other weather information on an Iridium GO!.
To download GRIB files, Weather Routing etc using a Windows 10/11 or Mac Computer you need to use the PredictWind Offshore App which you can download from here
Please see video on how to use the Offshore App.
Tip: Before using the Iridium GO! to download, use the WEB connection with high speed internet so you can get use to the Offshore App and the output.
Downloading with a high speed internet connection, or with the Iridium GO! is a very similar process. Please see tips below;
Ensure you are connected to your Iridium GO! device. Go to Wi-Fi settings and select the Iridium-XXXX Wi-Fi. Please note it is normal for the Wi-Fi connection to show error symbol or words "no internet access". The Offshore App will establish the Internet Connection for the Offshore App, but not for other programs.
After selecting the Download Tab on the top of the next page you will see Download Method choose 'Iridium GO!' from the drop down options, if not already selected.
Then select Next, select further info you would like to download, then select Next again
You will need 5 green bars to make a connection to get an acceptable data speed.
The data speed of the Iridium GO! makes it impractical to get large (above 150kB) GRIB files. We recommend you use the PredictWind Weather Routing to get this detailed information as the file size is very small.
If the signal strength is 5 bars, you can expect to download data at the rate of 12-18 Kbytes/min. 150kB will take around 12-15 minutes. Although you may have 5 bars of signal strength at the start of the connection (displayed in the Offshore App) this signal strength will drop below 5 bars, if there are any obstructions blocking the sky/horizon as each Iridium satellite passes overhead every 15 minutes. If there are any dropouts in the data connection the data rate will be slower due to the reconnect time.
Any dropouts in the connection are handled by the PredictWind "Smart Connect". So there is no need to manually restart the connection. Just click the "Download All" button and wait for all data to be downloaded. Please do not click on any buttons during the auto-reconnect process.
We recommend downloading new weather information ever 12 hours when the forecast models have updated..
Examples of Forecast Model update times:
The 50km resolution PWG forecasts are updated at 03:55 UTC and 15:55 UTC
The 50km resolution PWE forecasts are updated at 05:30 UTC and 17:30 UTC
The 50km resolution GFS forecasts are updated at 05:30 UTC and 17:30 UTC
The 50km resolution ECMWF forecasts are updated at 06:30 UTC and 18:30 UTC
For a complete Forecast update time schedule please click here
For GRIB files we recommend getting the 50km or 100km resolution PWG/PWE/GFS/ECMWF GRIB files with a 24hr timestep, 5 days, ,Wind, Pressure, Rain, Wave.
Please note : The High resolution GRIB files are too large to download on the Iridium GO! connection.
The Weather Routing automatically uses the highest resolution GRIB data anyway for the most accurate forecast. The Weather Routing pop up boxes as well as the Wind Tables reflect this information.
The GRIB Maps themselves are 50km at best where as the Weather Routing data could be as high as 1km or 8km resolution.
Use the GRIB map overlay to get an understanding of the general synoptic wind pattern and treat the pop up box or weather routing tables as the most accurate data.
CONNECTION ISSUES: If you are having trouble downloading data please make sure you methodically check all steps in the Iridium GO! Help > Troubleshooting Tips.