Google Now will keep your Cards loaded when you're offline

The latest Google Search update enables your cards to stay loaded when your phone is offline and you still want to check in whatever Google Now is suggesting. When you find yourself without a connection and trying to use Google Now, you'll be able to see when your content was last updated,
According to Google "Next time you’re on the subway and want to check on your day’s appointments with Google Now, you won’t have to worry about lack of cell service. Starting today your Google Now cards stay loaded, even when you lose service in the subway… or your favorite underground bar! "

All you have to do is update you Google Search and off you go.