I'm not sold on the weather disasters having the impact outlined in this post. Tornados, floods, wildfires, and honestly even hurricanes to a certain extent are pretty localized disasters. It's going to be very difficult for any of them to have drastic impacts on the nation as a whole. 

I live in an area that frequently gets hit with tornados, and we've had some very big ones in recent years. Wiped out entire neighborhoods. But the only people impacted were those right in the path of the tornado. I'm across town and my power was back in a day. Never even saw any significant damage with my own eyes, just on the local news reports. Obviously hurricanes are a lot worse, but they still only impact specific areas. Insurance rates may go up in those areas (or companies may refuse to insure entirely) and businesses will be slow to rebuild there, but it will have almost no noticeable impact on people in other parts of the country.

Same with epidemics starting in the wake of these disasters. That typically only happens in small nations where literally all of the infrastructure is wiped out. No clean water, no fresh food, and no one to bury the dead. Even with the worst hurricanes that have hit Florida you can drive like an hour north and be in a town with running water, functioning hospitals, and a Walmart with food on the shelves.