Time recently ran a Katrina - One year later article and included 4 maps of the country with risk assessments due to Hurricanes, Earthquakes, Floods and Wildfires.
Earthquake risk takes out the entire western side of the country and a good chunk of the mid-west. Floods take out much of the center and East coasts while Hurricanes take out the balance.
Overlaying the maps shows three small parts of the country that seem to avoid all 4.
1. Portions of Northern Michigan including the Eastern part of the peninsula
2. Small sections of North Central Nebraska
3. Small sections of Northwest Kansas