災 disaster

You SIGH as 2 disasters strike your birthday party - KKK plus a fire.

natural disaster ★★★☆☆
災 (disaster) + 害 (damage) = 災害 (natural disaster)

natural disaster - earthquake, fire, flood, your mother's flattus, etc.

disaster fire ★☆☆☆☆ NP
火 (fire) + 災 (disaster) = 火災 (disaster fire)

a slightly more newspaper-ish word for a harmful blaze.

disaster ★☆☆☆☆
災 (disaster) + 難 (difficult) = 災難 (disaster)

this means disaster - not in the sense of earthquakes or tsunami. Disaster in the sense of 'How was your trip to Tahiti?' 'Oh my god, it was a total disaster!!! First we missed the plane, then I got an infection, then on top of all that our hotel was run by zombies!'

災難　carries the sense of a bunch of random unconnected misfortunes. It never rains, but it pours, kind of thing.