There are only a handful of other weather disasters that can cause more damage than hailstorms, according to an article written by Anthony Campanaro for Yahoo! Voices:

According to the Federal Alliance for Safe Homes, hail causes more than $2 billion worth of damage per year to residential roofs in the United States, making it, year in and year out, one of the most costly natural disasters. Detecting roof hail damage after a hailstorm can be a difficult task. The best four things to look at when you are trying to determine the possibility of hail damage are the areas around the base of downspouts, gutters, metal vents, and roofing shingles.

Residents of Northern Virginia know that hailstorms and other forms of inclement weather are a natural part of the region’s climate. Overall, Virginia experiences its fair share of severe snowstorms, thunderstorms, and hail storms, which can take its toll on residential and commercial roofing. Due to the ever-present risk of hailstorms, roofing contractors in Northern Virginia remind residents to have their roofs inspected for damages following severe weather disturbances.

Cracks

Roofs that make use of tiles and shingles are susceptible to cracks after a hailstorm. These cracks will allow the water your roof normally deflects into your home, causing leaks and sagging in the attic space. If left unattended, water damage can lead to the formation of cracks which will grow in size,
especially during winter time when water that has collected in the cracks will turn into ice.

Dents

For most people, dents are the most obvious sign of hail damage. However, dents are not immediately obvious on most roofing systems. To properly inspect for dents, homeowners can run their fingers along shingles to feel any dents the naked eye may have trouble detecting. Dents that show signs of giving way are an indicator that a DIY patch job isn’t enough to repair the damage.

Although hailstones the size of golf balls and tennis balls grab national headlines, roofing experts, such as Northern Virginia Roofing, remind residents that even the smallest hailstones can cause significant and “hidden” damages to a roofing system. With this in mind, many Northern Virginia roof repair companies are happy to offer free inspections after a hail storm, allowing homeowners to choose the best course of action for repairing their roof.

(Article Excerpt and Image from Detecting Roof Hail Damage – 4 Determination Steps; Yahoo! Voices)