Rainy Season Roofing Checklist: How to Prepare Your Roof Before the Storms

The most useful rainy season roofing checklist covers six things: clearing gutters and downspouts, checking flashing and sealant, inspecting shingles for lifting or damage, trimming overhanging branches, checking the attic for existing moisture, and confirming drainage moves water away from the foundation. Most winter roof leaks don’t start during the storm. They start with a small problem that sat unaddressed through the dry months and finally got tested by the first real rain.

In the Bay Area, the rainy season generally runs from October through April, which makes late summer and early fall the practical window to get this done. Below is what to check, in what order, and what to do if you find a problem.

Download the printable checklist Want to take this outside with you? Download the free Rainy Season Roof Checklist (PDF), a two-page, print-ready version with checkboxes for every item below.

View Rainy Season Checklist

Before the Rain: Your Pre-Season Checklist

Work through these six items before the first major storm, ideally in September or early October, while the roof is still dry and safe to access.

Task	What You're Looking For	Why It Matters
Clear gutters and downspouts	Leaves, needles, grit, standing water	Clogged gutters send water back under the roof edge
Check flashing and sealant	Cracked caulk, lifted metal, gaps at chimneys and vents	Flashing failures cause more leaks than shingle failures
Inspect shingles	Lifting, curling, cracking, missing tabs, bare patches	Damaged shingles let wind-driven rain reach the underlayment
Trim overhanging branches	Limbs touching or within a few feet of the roof	Abrasion, debris drop, and storm-limb damage
Check the attic	Stains, musty smell, damp insulation, daylight	Reveals problems invisible from the ground
Confirm drainage	Downspout outlets, grading, pooling near the foundation	Water that doesn’t leave the roof area causes other problems

1. Clear the Gutters and Downspouts

Clogged gutters are one of the most common causes of winter roof damage, because water that can’t drain backs up under the roof edge and reaches the underlayment and fascia instead of running off.

What to do:

Remove leaves, pine needles, and accumulated grit from the full run of the gutter, not just the visible sections.
Flush each downspout with a hose and confirm water actually exits at the bottom. A gutter that looks clear can still have a blocked downspout.
Check that gutters are still securely fastened and pitched correctly toward downspouts. Sagging sections hold standing water.
If you see shingle granules collecting heavily in the gutters, that’s worth noting. Some granule loss is normal aging, but heavy accumulation can signal shingles nearing the end of their life.

2. Check Flashing and Sealant

Flashing, the metal installed at chimneys, vents, skylights, valleys, and wall intersections, is where a large share of roof leaks actually begin, since these transitions are harder to waterproof than open areas of shingles.

Look for cracked or shrinking sealant, flashing that has lifted or separated from the surface, rust, or visible gaps at any penetration. Sealant is not a permanent material, and it’s normal for it to degrade over several years of sun exposure.

One caution: resealing flashing yourself with a tube of caulk is a common temporary fix, but it often masks a problem rather than solving it. If flashing has physically lifted or separated, it usually needs to be properly reset rather than sealed over.

3. Inspect the Shingles

Look for shingles that are lifting, curling, cracked, missing, or showing bare patches where granules have worn away, since any of these let wind-driven rain get past the surface layer.

You can do a useful first pass from the ground with binoculars. What to note:

Lifted or curling edges, especially along the roof edges and ridges
Missing tabs or visibly displaced shingles after a windy stretch
Dark or bare patches indicating granule loss
Buckling or waviness, which typically points to a moisture or ventilation problem underneath rather than a shingle defect

For the fuller picture on what these signs mean, see what causes shingles to fail. If your roof is nearing replacement anyway, it’s also worth reviewing the best roofing shingles for durability and weather resistance before choosing a replacement product.

4. Trim Overhanging Branches

Branches that touch or hang directly over the roof cause two problems: constant abrasion that wears down shingle granules, and a steady supply of leaves and needles that clog gutters and hold moisture against the roof surface.

Aim to keep limbs several feet clear of the roof surface where practical. This also reduces the risk of a limb coming down on the roof during a wind event, which is a far more expensive problem than a trimming job.

Overhanging trees also contribute to moss and algae growth by keeping sections of the roof shaded and damp, which is a common issue on north-facing slopes in the Bay Area.

5. Check the Attic

The attic often reveals roof problems that aren’t visible from outside, including existing leaks, inadequate ventilation, and moisture buildup that can cause damage even without a single drop coming through the ceiling.

With a flashlight, look for:

Water stains or dark streaking on the underside of the roof deck
Damp, compressed, or discolored insulation
A musty smell, which can indicate moisture even when no stain is obvious
Daylight visible through the roof deck
Blocked soffit vents, often caused by insulation pushed into them

Ventilation matters more than most homeowners expect. A poorly ventilated attic traps moisture through the wet months, which contributes to deck deterioration and shortens shingle life from underneath.

6. Confirm Water Actually Leaves

Check that downspouts discharge well away from the foundation and that the ground slopes away from the house, since a roof that drains correctly into a spot that pools water has just moved the problem rather than solved it.

Walk the perimeter and look for low spots where water collects, downspouts that dump directly against the foundation, or splash blocks and extensions that have shifted out of position over the summer.

During the Rainy Season: What to Watch For

Once the rain starts, the most important signs are new interior stains, dripping at light fixtures or vents, damp spots on exterior walls, and gutters overflowing during moderate rain rather than only in heavy downpours.

A few things worth knowing:

A ceiling stain rarely sits directly under the leak. Water often travels along framing before it drops, so the entry point can be several feet away from where you see it.
Overflowing gutters in moderate rain usually means a blockage formed since your last clearing, particularly after a windy stretch that dropped fresh debris.
Interior condensation on windows and in the attic can look like a leak but may be a ventilation issue instead. Both are worth addressing, but they have different fixes.
Document anything you find. Photos with dates are useful for both insurance claims and contractor conversations later.

When to Call a Roofer Instead of Handling It Yourself

Call a professional if you find active leaking, damaged or lifted flashing, missing shingles, sagging areas in the roof deck, or any problem that would require walking on a wet or steep roof to inspect.

Wet roofs are genuinely dangerous, and this is the main reason the pre-season timing matters. A checklist item that’s simple in September becomes a hazard in January.

If you do bring someone in, it’s worth confirming their licensing and insurance first, particularly during storm season when door-to-door operators become more common. See how to hire a legitimate roofing contractor for what to verify before signing anything, and how to check that roofing work meets code standards for confirming the repair was done correctly afterward.

FAQ

When should I do my rainy season roof prep?

Late summer through early October is ideal in the Bay Area, before the first significant storms arrive and while the roof is still dry enough to inspect safely. Waiting until rain is in the forecast usually means competing for contractor availability at the busiest time of year.

How often should gutters be cleaned?

At least twice a year for most homes, typically late spring and early fall. Properties with heavy tree cover, especially pines, often need more frequent clearing, sometimes several times during the fall alone.

Can roof repairs be done during the rainy season?

Emergency repairs can and should be done whenever they’re needed, but many roofing materials require dry conditions to install and seal correctly, and self-sealing shingle adhesive strips in particular may not bond properly in cold or wet weather. Planned work is generally better scheduled for drier months when possible.

Does a new roof need this checklist too?

Yes, though a newer roof will typically need less attention. Gutters still clog, branches still grow, and flashing sealant still ages regardless of how old the shingles are. Regular checks also help preserve manufacturer warranty coverage, which often requires documented maintenance. See material warranty vs. workmanship warranty explained for what that coverage actually involves.

What if I find a problem but can't afford a repair right now?

Document it with photos, address what you safely can (clearing gutters and trimming branches are low-cost and make a real difference), and get at least one professional assessment so you know whether you’re dealing with something urgent or something that can reasonably wait for spring.

The Bottom Line

A rainy season roofing checklist isn’t about predicting where a leak will happen. It’s about removing the common, preventable causes before the weather tests them. Clear gutters, intact flashing, sound shingles, trimmed branches, a dry attic, and drainage that actually carries water away cover the large majority of what goes wrong during a wet Bay Area winter.

The work is far easier and safer in September than in January, and catching one lifted flashing detail in advance is considerably cheaper than repairing a ceiling after the fact.

Dean M.

General/Project Manager at Acker Roofing Inc. with over 45 years in the roofing industry. As a GAF, CertainTeed, and Brava Tiles certified professional, I’ve managed countless projects and enjoy sharing tips and insights to help property owners protect and get the most out of their roofs.