AppleScript:If commmad dosen't execute

everybody, I am a beginner at AppleScript so I really don't know a lot. Anyways I have been trying to make the user select from a list of situations and then based on what they chose to have an appropriate response. However, I have run into a few problems,1. The script runs but doesn't display the notification. 2. Is there a better way than just chaining a lot of IF statements?

PS: I am nowhere near finishing this whole script.

on run
choose from list {"Thunderstorm", "Flood", "Heatwave", "Hazmat"} with prompt "Please select one of the emergency situations below" without multiple selections allowed and empty selection allowed
return the result as string
if string is Thunderstorm then display notification "hello"

end run