Typhoon Merbok was a federally declared disaster, so the loss is allowed on your tax return. There should be section for Casualty losses on the main Deductions page.
However, you can only claim your unreimbursed loss. If you had insurance coverage, you could only claim your deductible, if you paid one. If you didn't have insurance coverage, you can list the fair market value at the time (what the price for a used car of the same make, model, mileage and condition would have been on that day.) If you had insurance coverage but didn't make a claim, your tax loss is limited to what your loss would have been if you had made an insurance claim. If you got a partial reimbursement from the state of Alaska or FEMA, that also offsets your deductible loss.
There is a loss deductible on your tax return of $100 per event and 10% of your adjusted gross income overall. Then any allowable amount is an itemized deduction. So you won't get any benefit if you take the standard deduction, and your loss will be limited even if you itemize. (For example, if your income is $75,000 and your loss was $10,000, your loss deductibles will be $7,500 plus $100 so the actual itemized deduction would be $2,400, added to your other itemized deductions.
Also note that if you deduct the loss now, but get reimbursed by Alaska or FEMA in the future, that reimbursement will be taxable income.
