As a rule of thumb, when there is a delay to Air Traffic Control or weather they will seldom compensate you for the delay. These are the two factors that are out of their control, which they will use to explain any delays. The best thing that you can do when these two factors occur, is to ask for a meal voucher at the airport or a re-route through another city (this of course depends on where they delay is located). Trying to get a hotel voucher really depends on your attitude with the agent and status. Most times they will try to push off a heavily discounted hotel room that you will pay for, due to these delays.