"Material" may have a definite % meaning. I know it does in other contexts. So suppose the storm may reduce quarterly earnings by more than 10%, but won't reduce annual earnings by more than 10%. This makes sense mathematically, and would justify the sentence.
"We fully believe that the storm will not have a material impact, however, there remains the possibility, however remote, that it could due to our insurance company putzing around with the payout, or the maintenance people farting around and not getting the lines up and operational."