With the approaching storm you need to go through your boat systems to make sure that your boat is floating after the storm.
Check your batteries for water and charge. If you have a land charging system make sure that you use it up until the storm starts. Check your float switches which every boat should have located at the lowest portion of your bilge. You can check this by simply pulling the float switch upwards and listening for the pump to engage. Spare anchors to secure the boat away from the dock. Spare dock lines to secure the boat.

Fuel... Depending on the weight of your boat you need to maintain a heavy sitting position. Adding fuel midship gives stability.
Scuppers clear of debris. Look around!!!!

Check the boats around you for stability. Its not going to matter how well you prepare if the guy next to you does not prepare.
Check your insurance policy to make sure it is active!

Good Luck,