El Niño Is Coming to Southern California. Is Your Roof Ready?

Southern California homeowners are used to thinking about roofs in terms of heat, wildfire, and sun exposure. But every few years the Pacific flips into an El Niño pattern, and the conversation changes overnight. The storms that follow can drop more rain in a single week than a typical LA winter sees in two months — and roofs that looked fine in August often reveal problems the first time water pools in a valley or wind drives sideways into aging flashing.

The good news is that most El Niño roof damage is preventable. A focused inspection in late summer or early fall, before the first major storm system arrives, catches the small failures that turn into ceiling stains, drywall damage, and mold remediation later. This is what we check on Southern California homes before a rainy winter, and what you can look for yourself from the ground or a safe ladder.

El Niño winters do not just bring more total rainfall. They tend to arrive in intense, concentrated bursts separated by dry spells. A roof that can handle a light drizzle for weeks may struggle when a three-day atmospheric river dumps several inches, because the water finds the path of least resistance: a lifted shingle, a cracked tile, a gap in the valley metal, or a clogged drain on a flat roof section.

Wind matters too. Santa Ana events can precede or follow winter storms, and sustained 40- to 60-mile-per-hour gusts peel back poorly sealed shingles and deposit debris into gutters that were already marginal. The combination of wind and heavy rain is what separates a minor leak from a major interior repair.

On pitched roofs, the first things we inspect are the shingles or tiles themselves. Missing, cracked, or curled shingles are easy to spot from the sidewalk. On clay or concrete tile roofs, the tiles themselves are often still intact while the felt underlayment beneath them has dried out. That underlayment is the actual waterproofing layer, and once it tears or decomposes, the roof can leak even though every tile looks perfect.

If your tile roof is more than 20 years old, the underlayment is likely the item that needs attention. A few replaced tiles will not solve a systemic underlayment failure. On composition shingle roofs, granule loss, exposed fiberglass, and any shingles that no longer lie flat are signs that the roof is nearing the end of its service life.

Flashing is the thin metal or membrane that seals the intersections of a roof: where a wall meets a slope, where a chimney or vent penetrates the field, where two roof planes form a valley. It is also the most common source of leaks we see in older LA homes.

Look for gaps between the flashing and the wall, rusted or lifted metal, missing sealant, or any place where debris collects in a valley. Valleys should be clean and free of leaves before the rainy season. If water cannot flow freely, it will sit until it finds a way in.

Many LA homes have flat or low-slope sections: additions over garages, covered patios, rooftop decks, and modern low-slope designs. These areas do not shed water the way a pitched roof does, so they rely entirely on drains, scuppers, and membrane integrity.

Check that drains are clear of leaves and sediment. Make sure strainers are in place. Walkable decks should have a qualified roofer inspect the membrane, especially at railing posts and door thresholds. A flat roof that has been patched multiple times is usually a candidate for a full membrane replacement rather than another patch.

Gutters do not just catch water; they control where it goes. When they overflow, water runs behind the fascia, into the eaves, and down the exterior walls. In older homes, that water can wick into framing and cause rot that is expensive to repair.

Clean gutters before the first storm. Test downspouts by running a hose into them and confirming water exits well away from the foundation. If a downspout empties right next to the house, add an extension or a splash block. A roof that is in perfect condition can still leak if backed-up gutters force water backward under the edge metal.

You do not need to go on the roof to know something is wrong. Water stains on ceilings, bubbling paint, discolored drywall corners, and a musty smell in closets or attic spaces after rain are all symptoms of an active leak. Rusted nail heads poking through the underside of roof decking are another classic indicator.

If you spot any of these, schedule a roof inspection before the next storm. Small leaks grow fast once the underlayment is saturated, and the damage spreads from the roof deck to insulation, drywall, and even electrical fixtures.

Roofing contractors' schedules tighten fast once the first major rain is in the forecast. Waiting until the weather report turns red means you are competing with every other homeowner who just noticed a stain. In late summer and early fall, crews are more available, materials are in stock, and you have time to get the work done right before water is actively entering the house.

A pre-El Niño inspection is not just a sales visit. It should produce a written report with photos, a clear list of priorities, and a proposal for anything that needs repair or replacement. At California Trusted Contractor, we perform these inspections across Los Angeles, Ventura, Santa Clarita, and the San Fernando Valley. If your roof has not been looked at in the last year, now is the time.