How Bad Weather Can Impact Your Roof

Weather of any kind can impact your roof. Even in sunny, mild climates, exposure to sun, day after day, takes a toll on your roof covering. However, bad weather can multiply the damage.

In the San Francisco Bay Area, long periods of drought, followed by a series of bad weather winter storms packed a double punch.

Years of Northern California Drought

Roofs covered in composite shingles or tar and gravel, aged by the unrelenting sun during decades of drought, take their toll on residential and commercial roofs.

Damage from extreme heat and the sun’s UV rays cause the materials to dry out and become brittle. They may crack, buckle or tear, making them susceptible to further damage when bad weather in the form of strong winds or heavy rains come.

Heavy Rain

Almost 10 inches of heavy rain fell in December 2022, after years of drought. Then, the Bay Area was hit by an atmospheric river that brought torrential rains for days at a time. That spate of bad weather took its toll.

The soil, saturated and flooded in many communities, saw trees come down on houses after root systems gave way. Roofs were damaged and lives were lost.

Roofs were impacted in other ways, too. Composite roofs have three layers. The first is the backing material, then the asphalt and then a layer of grit or granules.

During the life of your roof, the granules may become thinner, much like the hair on your head. It’s all part of the aging process.

What you don’t want, are large areas bare of granules. During bad weather that brings heavy rains, more granules may be lost, affecting the efficiency of your roof.


The series of bad weather storms continued in January bringing thunderstorms, lightning strikes and hail.

According to the Midwestern Regional Climate Center, “Hail stones are a frozen form of precipitation that occurs when thunderstorm updrafts lift rain above the freezing level in the atmosphere.

When hail stones become too heavy to be lifted by the updraft, they fall to the ground… Hail stones come in various sizes and shapes and can cause large amounts of damage to property.”

Hailstones can damage shingles, crack tiles and generally wreak havoc, if the hail stones are large enough. They also remove granules from shingles by the sheer force of their impact.

The odd thing about hailstorms is that they do damage according to patterns or hail swaths. That means a hailstorm may come down heavily in a swath covering an acre or one that is up to 10 miles wide and 100 miles long depending on the movement of the storm.

So, it is possible for some homes in a neighborhood to be hit, while leaving other homes relatively free from harm.

Severe Winds

The bad weather storms of early 2023 also brought winds of up to 80 miles per hour. Can your roof take those gusts? High winds can negatively impact you roof in a number of ways. Winds can rip off damaged shingles, that are cracked or curled. Strong winds have even torn heavy clay and slate tiles from roofs.

If trees are not kept trimmed, when bad weather hits, small to large branches can break off and land on your roof, causing damage to the shingles or tiles.

If a branch is big enough it can even break through and damage the roof deck and the framing. Keeping vegetation trimmed and healthy is a great way to minimize damage.

Staying on top of maintenance can save you big headaches.


Staying on top of maintenance can save you big headaches. It is a good idea to take a close look at your roof at least once a year. Keeping your roof free of debris and making sure your gutters are clear is a great first step.

Depending on the height and mass of your roof, you may be able to get a look at how the surface covering is doing, without getting on the roof itself.

For most homeowners, climbing onto your roof is something you may want to leave to the professionals. If you have a home with a relatively flat roof, even walking on it can do some damage.


If you have questions, or concerns contact us today. One of your professionals will be happy to advise you on maintenance and repair issues.