Swift: how to schedule local notifications with dynamic content

I have a weather app for iOS, and I'd like to allow the user to receive a notification each morning at a time of their choosing which would fetch the weather forecast for the day and display a notification. I'd like to avoid using push notifications, and I thought I might be able to use local notifications, except I can't see a way to fetch the content to be shown from a server. It looks like the content has to be set at the time of scheduling. Is that right? That makes me think I might be able to register my application to use background execution to periodically fetch the weather and schedule a notification with the latest content, but this seems wasteful. In short, I'd like to tell iOS to run a specific function at a specific time. Is there a good option for this that I'm missing? Are push notifications the only/best way to accomplish this sort of thing?