It doesn't really compare with i) Sirius Weather over a chart plotter; or, if you're in cell range, Intellicast, Storm, and other apps. However, cell coverage is limited to close-in distances.

We have Weathertrack -- which is application that you can combine with your "routes" and load-up a few days in advance.

However, for coastal cruising (and, at least on the East Coast, a pretty good distance offshore, nothing compares with Sirius Weather.