Hail Damage
Hailstones are chunks of ice produced by the turbulent updrafts of thunderstorms. Hailstones vary in size, shape, and hardness. Thus, hail impact-caused marks on a roof and surroundings have various sizes, shapes, and depths. Hailstone-caused impact marks are generally rounded, but not perfectly circular.
The larger the hail, typically the fewer and farther apart the hailstones fall. Since the patter of hail fall is random, their impact marks on the roof are widely distributed. Hail impact marks of varying sizes, shapes, and depths can appear in metal vents, flashings, air conditioning unit fins, and other exposed surfaces. These are indicators of hailstone size, frequency, and fall direction. Keep in mind that hail usually is wind driven, thus the windward side of the roof would sustain the most direct impacts. This can be important because perpendicular impacts transfer the most impact energy to the shingles.