The key line is where the water came from. Water that falls and enters through a storm-opened roof can be covered by a homeowners policy; water that rises off the ground and flows in is flood, and it is excluded. Same house, same storm, different coverage.
NFIP flood policies typically carry a 30-day waiting period, so buying coverage as a storm approaches does not help. If you are in or near a flood-prone area of the Kansas City metro, the time to add it is well before the season.
After a flood loss, document everything and separate flood damage from any wind or roof damage, because those may fall under two different policies. A restoration company can file with both.