As the holidays roll in and the first cold fronts move through Wisconsin, most homeowners stop thinking about their roofs. Snow starts to build up, people are traveling or hosting family, and summer storms feel like a long time ago.
But in the roofing and insurance world, this time of year is when past hail damage becomes more important than most people realize. Hail damage shows up on the shingle the day of the storm. You can see bruising, granule loss, soft spots, or visible impact marks. Homeowners might not always notice it, but the damage is there immediately. What homeowners usually do not see is how that initial impact changes the way the roof ages over the next several years.
What hail actually does to a shingle
When a hailstone hits, it can knock off granules and sometimes fracture the fiberglass mat underneath the surface. Industry inspectors and roofing engineers consistently show that even smaller hail can weaken the shingle structure without creating an obvious hole. The roof may appear fine at a glance, but the damaged spot is now the weak point in future weather.
Once granules are loosened or lost, the asphalt underneath is exposed to more sunlight. Over time that area dries out faster, becomes more brittle, and ages quicker than the surrounding shingles. This is legitimate hail damage that begins on day one, but the long-term effects are not noticeable right away.
Why winter matters so much
Winter is the season that speeds up this breakdown. As temperatures swing above and below freezing, moisture works into the bruised area. When it freezes it expands. When it thaws it contracts. Roofing engineers refer to this as the freeze and thaw cycle, and it puts extra stress on shingles that were already weakened by hail.
This process usually does not cause sudden leaks in January. What it does is slowly wear down the damaged sections over multiple winters until they eventually become thin, brittle, or vulnerable. Snow hides the roof for months, which makes it even harder for homeowners to notice how much that area has changed.
Where homeowners get caught off guard
The real surprise often appears years later when another hailstorm hits or when the roof finally starts showing interior symptoms. By that time the original hail hits may look aged or worn. In many claims, insurers will only cover damage that can be clearly tied to the most recent storm. Anything that appears to have occurred in earlier years can be considered pre existing or unrelated to the new event. And depending on your policy, you may only have 6-12 months to file a claim from the date of the storm.
This is a common situation in insurance. The shingles were damaged by hail originally, but without documentation from that first storm, the older impacts are much harder to include as part of a later claim. This is why documenting damage immediately after a storm is so important.
What homeowners should know heading into the holidays
Hail damage begins on the day of the storm, but it often becomes a long-term issue through winter. Freeze and thaw cycles, UV exposure, granule loss, and natural aging all interact with that original bruise. Over a few seasons those damaged areas can break down enough to cause leaks or create complications when a future claim is filed.
Most homeowners are not thinking about their roof during the holiday season, and that is exactly why these problems slip through the cracks. Summer storms start the process. Winter, especially repeated winters, is where the long-term consequences take shape.