Should I replace the roof?

[Aaron Lancaster]

I had my roof inspected after some recent storms in the area and the roofer told me he strongly recommends I replace the roof within the next year. Although no leaks were spotted, he said that because my roof is at least 15 years old (not sure of the exact age), the asphalt shingles are rough (petrifying) and suffering heavy granular loss. He said that one more hail storm with quarter-sized hail or larger could possibly destroy any remaining granules and leaks could sprout. 

The property is in Northwest Arkansas so we get very hot summers, very cold winters, and semi-frequent tornados and hail storms, so roofs usually don't last longer than 15 years around here (according to the roofer). I have catastrophic insurance ($10k deductible) so although I might be able to file a claim, it likely wouldn't be worth dealing with the insurance company.

Any thoughts on whether I should replace it this year or wait until problems occur?