This is a good question. You can use this feature for pre-flight weather. You can update from any internet computer, ie the FBO, Office or your home. One the update site, just check the TFRs & Metars and create an update. It only takes a few second to perform and you have the current metars at the time or prefilght. This is agreat for a short flight, however for longer flights, it will become dated. We hear most owners update these before taking off or heading to the airport. It's not live weather, just the next best thing.
We are currently developing Weather via ADS/B for a future release. This will ensure live weather prvided you have an ADS/B receiver. More information to come on this upcoming feature.