Not really much to add beyond the title question. It seems that hurricanes weaken when they make “landfall” on even relatively small islands. For that matter, why don’t they form over land? It seems like the same atmospheric conditions creating a hurricane would exist over land.
For that matter, why do hurricanes only get created in tropical climates?
Hurricanes suck their energy from the heat in the water. Land does not give up the heat as readily–there have been some proposals for massive water chilling to stall dangerous hurricanes, but that would be a huge undertaking.
Ocean water temps have to be 79 degrees farenheit and above in order for a hurricane to form. This is why there’s a “season”, it corresponds to a general increase in ocean temps. The warmer the waters it travels through, the greater the potential strength of the hurricane.
Thank you all very much. I guess I don’t need to worry here in Wyoming. 
This is why hurricanes tend to strengthen as they cross the Gulf of Mexico- the water in the Gulf is warm.