How to Spot Wind Damage on Your Roof After a Santa Ana

Santa Ana Season Is Roof Damage Season

Our worst roof wind comes in a short, fierce window. The National Weather Service describes Santa Ana winds as air that pours east to west through the mountain passes of Southern California, and says they can cause major property damage.²

A National Weather Service climate bulletin puts these events most often in October through March, usually lasting one to five days, and sometimes ten or more.³

We wanted the local numbers, so we counted them. We went through every gust the weather station at Ontario International Airport logged from January 2016 through December 2025, using the public archive kept by the Iowa Environmental Mesonet.¹ We kept the strongest gust of each day.

Over those ten years the station logged 84 days with a gust of 40 mph or more. 81 of those days fell between October and March, and 80 of the 84 peak gusts came out of the north or east, the Santa Ana direction.¹

It logged 44 days at 47 mph or more, all of them in October through March. January led with 15 of those days, then December with 9 and November with 8.¹

The top reading was 76 mph late on January 9, 2025, out of the northeast. The second was 70 mph on October 26, 2020.¹ So yes, October can bring the real thing.

Where Wind Hits a Roof First

Wind does not push evenly on a roof. It pulls hardest at the edges and the high points.

A paper published by the International Institute of Building Enclosure Consultants found wind damage on shingle roofs is worst where wind forces run higher, at the eaves, hips and ridges.⁶ The tab usually fails right at the top of its exposed part, just below the shingle above it.⁶

Tile follows the same pattern. Florida's Division of Emergency Management says older mortar set hip and ridge tiles are the first to blow off, once gusts start passing about 80 to 90 mph. It says the first row of tiles at the eaves sees wide damage when gusts climb past 100 mph.⁷

Ontario gusts rarely reach those numbers, but our tile roofs are old. Mortar that has cracked and let go after 25 summers does not need a hurricane to drop a ridge cap. Start every check at the ridge, then the hips, then the rakes and eaves.

The Signs on a Shingle Roof

A crease is the giveaway. In wind testing cited in the IIBEC paper, every shingle that came unstuck showed at least a crease.⁶ On a newer, soft shingle that crease can be faint, so look for a straight line across the top of the tab.

Missing tabs or whole shingles. A clean gap that shows the darker shingle below, nail heads, or bare felt means the wind won. Pieces in the yard or the gutter tell you which side of the house took it.

Lifted edges that flap. A tab that lifts and drops in a breeze has lost its seal. Once it starts moving, every gust bends it more, and then it creases, flips and tears.⁶

Not every loose shingle is wind. The same paper says a tab that is unstuck but has no crease, fold, tear or missing piece is not wind damage.⁶ It also notes that shingles tend to stay sealed for about the first four to five years, and that unsealing gets more common after that from age, heat cycles and install mistakes.⁶ An adjuster will look for that difference, so it helps to know it before they arrive.

If you are buying new shingles, look on the bundle for the ASTM D7158 class. The Asphalt Roofing Manufacturers Association lists Class D for basic wind speeds up to 116 mph, Class G up to 155 mph and Class H up to 194 mph, all as three second gusts, on a roof no taller than 60 feet in standard exposure.^5] Our [shingle roofing page covers what goes under them.

The Signs on a Concrete Tile Roof

Concrete tile is heavy, so wind rarely peels a field of it. The trouble spots are the pieces held on by mortar or a single nail.

Ridge and hip caps out of line. A cap tile that sits crooked, or a gap where gray mortar shows, means the bond broke. Florida's guide says to look along ridges, gable edges and eaves for cracked, broken or loose tile, and to note whether the caps are set in mortar or fastened to a ridge board.⁷

Tile shards on the ground. A broken cap often lands in the yard or on a lower roof. Look before you mow.

Slipped field tiles. A tile that slid down a few inches leaves a dark strip of bare underlayment above it. That strip is now taking the sun and the rain the tile used to block.

Light in the attic. Florida's guide suggests going into the attic on a sunny day and looking for daylight through cracks or holes, and for water stains on the wood, with extra care near chimneys, vents and spots where the roof changes slope.⁷

Stay off the tile. The same guide warns that walking on the roof can break the mortar bond or crack tiles.^7] A ladder at the eave and a pair of binoculars do the job. If a few tiles need swapping, our [tile roofing page shows how that repair works.

What to Do the Day After a Wind Event

Write down the date and time. You don't have to guess at a gust. The airport readings are public, and they show the day and hour the wind peaked.¹

Photograph before anything moves. Shoot the roof from every side of the house, the pieces in the yard and the attic. Wide shots first, then close ups.

Cover any opening before the rain. Ontario's normals put 9.97 of its 11.64 yearly inches of rain in November through March, the same stretch as the strongest gusts.^8]1 A missing shingle or a slipped tile can sit dry for weeks and then leak the first night it rains. If the deck or underlayment is open to the sky, an [emergency roof repair or a tarp buys time.

Get a written estimate with photos. A roofer who goes up and shoots each damaged spot gives you a record you can hold up next to an adjuster's report. Our roof repair page lists the common fixes.

Know how your insurance reads wind. The Insurance Information Institute says windstorm damage is covered under homeowners insurance, while an old roof on an actual cash value policy can be paid down a lot for depreciation.^9] Our [roof leak insurance guide walks through where the line between wind and wear falls.

For a free written estimate with photos of every spot the wind found, call Ontario Roofing at (909) 404-9464.