Hurricane Andrew's winds in 1992 are responsible for the above picture--a piece of plywood through a palm tree!
That Cat 5 hurricane shows just how strong wind can be. Dorian is expected to pack 140 mph winds at landfall and, intuitively, you might think a 140 mph wind is twice as strong as a 75 mph wind, but wind force is exponential which means that with each mile per hour, the devastation is that much worse.
Look at the NWS chart below:
If 75 mph is the base, then a 140 mph wind is 147 times more destructive.
Our 2008 Hurricane Ike came in with 110 mph winds and Dorian could be 8 times more destructive than Ike in terms of wind! And for a 20-story highrise, 140 mph winds will translate to 163 mph winds at the top!
And that's just wind. Storm surge is expected to run 10-15' -- this is not a wall of water like a tsunami that just arrives. Surge is rising water that will push not just to the coast but cause flooding of rivers, inlets, bays, streams.
And on top of the surge comes a foot of rainfall, if not more, exacerbating the flooding.
You can understand the urgency for Florida residents to evacuate or take precautions. If you have friends or family there, make sure they understand that if this storm t-bones the state, which it looks like it will, their worst hurricane in almost 30 years is on the way.