There is currently no way to play official steam games without internet. And most probably there won't be in a future.. You have to watch weather forecasts, forsee the geological disruptions, watch closely constrution yards in area where are cables/signal to your provider, also check how your provider is routing you to the internet so you can turn into and offline mode in advance..
...they probly expect that world won't collapse or something ;)
Sometimes my internet gets shut off, when this happens and I start steam up it will say "updating steam" and never load so I can't play any offline games. Is there any way around this?
Make sure the option "Remember My Password" is ticked when you login and the option "Don't save account credentials on this computer" in settings>Account is unticked. Obviously only do this on a PC that you trust.