Deductible losses. Deductible casualty losses can result from a number of different causes, including the following...
Storms, including hurricanes and tornadoes...
(note that the deductible losses have to be greater than 10% of your adjusted gross income.)
Figuring a Loss
Figure the amount of your loss using the following steps.
1 Determine your adjusted basis in the property before the casualty or theft.
2 Determine the decrease in fair market value of the property as a result of the casualty or theft.
3 From the smaller of the amounts you determined in (1) and (2), subtract any insurance or other reimbursement you received or expect to receive.
Gain from reimbursement. If your reimbursement is more than your adjusted basis in the property, you have a gain. This is true even if the decrease in the FMV of the property is smaller than your adjusted basis. If you have a gain, you may have to pay tax on it, or you may be able to postpone reporting the gain. See Publication 547 for more information on how to treat a gain from a reimbursement for a casualty or theft.