Frozen Pipe and Ice Dam Claims in a Strong El Niño Winter: A Field Checklist for Adjusters

NOAA's Climate Prediction Center says this winter will be shaped by a strong El Niño, not a La Niña. In its October 8, 2026 ENSO discussion, CPC kept an El Niño Advisory in effect and put the odds of a strong-to-very strong event lasting through January–March 2027 at better than 83%. NOAA's official winter outlook, released October 15, leans warmer than normal across much of the northern U.S. and wetter than normal across the South and East Coast.

A warm northern tilt sounds like a slow freeze season. It might be. But last January's Winter Storm Fern showed where freeze claims really pile up: in the South, in homes that weren't built for hard cold, after the power goes out. Here's what the outlook says, what Fern taught the industry, and a field checklist for the frozen pipe and ice dam files that will come in anyway.

What NOAA is forecasting for December through February

  • El Niño strength: CPC's October ENSO discussion put the Niño-3.4 index at +2.1°C. It gave a 70% chance that the November–January index will top +2.5°C, which would make it the strongest event since at least 1950. This is the first El Niño since 2023–24, and the comparisons now point to 2015–16, the last very strong one.
  • Temperature: Warmer than normal is favored for the Pacific Northwest, northern Rockies, Midwest, Mississippi Valley, much of the East and Alaska. Parts of the Southeast, including Florida, lean toward near normal.
  • Precipitation: Wetter than normal is favored for the Southwest, South and East Coast. Parts of the northern Rockies and Great Lakes lean drier.

National Weather Service Director Ken Graham said a very strong El Niño will likely shift the jet stream south and east, favoring stormier weather in the South, and warned that heavy rain on dry ground can cause flash flooding and mudslides.

The fine print: cold snaps still happen

The NWS office in La Crosse, Wisconsin put it well in its winter 2026–27 outlook. Strong El Niño winters have historically been among the warmest there, and conditions this year make Arctic outbreaks less likely. But other patterns can still drive cold outbreaks over a week or two, and snowstorms will still happen. Their number and timing can't be predicted a season ahead.

What it means for you: Plan for a winter workload weighted toward the South and Southeast: water intrusion, flooding and severe storms, with freeze claims arriving in bursts whenever a cold snap does break through. Fewer northern freeze events doesn't mean zero.

Last winter's lesson: Winter Storm Fern

Fern hit from January 23 to 26, 2026, stretching from Texas into New England. Verisk's initial estimate put insured losses at up to $4 billion and said freezing would be the largest source of loss. Ice up to an inch thick fell in parts of the South, and freezing rain knocked out power across the Southeast and Mid-Atlantic, which raised the risk of burst pipes in homes that rely on electric heat. KCC's estimate, reported by Business Insurance, was higher, at $6.7 billion in privately insured losses, with the largest losses in Texas and Tennessee.

Verisk said that if its estimate held, Fern would rank as the third costliest U.S. winter storm on record, behind Uri (2021) and Elliott (2022). The lesson for adjusters: a short, hard freeze in a warm-climate region, combined with power loss, can produce a wave of interior water claims all at once.

Why freeze claims deserve your attention

They aren't small. In a January 2026 release, State Farm reported more than 20,000 freeze-related water claims from 2024 through June 2025, more than $628 million paid and an average payment above $30,000. Its top five states by total paid were Illinois, Oregon, Washington, Texas and Tennessee. That's one carrier's data, but it shows that a frozen-pipe file often involves full mitigation, tear-out, rebuild and contents work.

State Farm's guidance to homeowners is also worth knowing, since coverage questions often turn on it: keep the home heated to at least 55°F, let faucets drip on cold nights, and know that pipes in attics, crawl spaces and exterior walls are most at risk, especially below 20°F.

The coverage question you'll be documenting

In the ISO HO-3 form, as summarized by coverage attorneys, water damage from plumbing or appliances that froze is excluded unless the insured either used reasonable care to maintain heat in the building or shut off the water supply and drained the system. Some carrier forms go further and apply the freezing exclusion only while the home is vacant, unoccupied or under construction.

Your job isn't to decide coverage on a hunch. It's to collect the facts the coverage decision depends on. Disputes tend to turn on a few questions:

  • Did a normal thermostat setting count as "reasonable care," even though a pipe in an uninsulated exterior wall froze anyway?
  • Was the home vacant (empty of contents) or just unoccupied (no one living there that week)? The policy may define these differently, and courts have too.
  • Did the heat fail because of a utility outage the insured couldn't control?
  • Is this sudden freeze damage, or long-term seepage, corrosion or wear?

Always read the actual policy form on the file. Wording varies by carrier and by edition.

Frozen pipe claim field checklist

Heat and occupancy

  • Photo of the thermostat: set point and current reading.
  • Heating system type, fuel or power source, and condition. Is it working now? Was it working then?
  • Utility outage records or outage-map screenshots for the address and dates, especially after an ice storm.
  • Occupancy timeline: who was living there, when they left, when they came back.
  • Evidence of vacancy or occupancy: furniture, food, mail, utility use.

The break itself

  • Location of the failed pipe: exterior wall, attic, crawl space, garage, unheated addition.
  • Insulation present or missing at that location, with photos.
  • Pipe material and approximate age.
  • Close-up photos of the split or failed fitting.
  • Preserve the failed section, tagged and photographed, for possible expert review or subrogation.

Timeline and mitigation

  • When the insured discovered the water and when the main was shut off.
  • Who shut it off, and how long water ran.
  • When the mitigation company arrived; get their moisture logs and photos.
  • Any signs of earlier leaks, staining or corrosion that point to long-term seepage.

Scope

  • Moisture mapping across affected rooms and floors, including ceilings below an attic or second-floor break.
  • Water category and drying class, documented per IICRC terms.
  • Contents affected, separated from structure.

For how to turn those readings into a defensible mitigation estimate, see our guide to estimating water mitigation in Xactimate. If you write a lot of these files, our Complete Water Mitigation Estimating Template for Xactimate loads about 300 line items so you're trimming a complete scope rather than building one from memory.

Ice dam claim field checklist

Under El Niño, ice dams may be less common across the northern tier this year, but any good snow followed by a cold spell can still produce them. United Policyholders says interior damage from ice dams is generally covered when notice is timely and the damage isn't solely from known, pre-existing roof problems. Common disputes include actual cash value vs replacement cost, pre-existing damage or construction defects, scope and pricing, and matching.

The core of an ice dam file is separating two things: the condition of the roof covering, which may be wear or maintenance, and the resulting interior water damage, which is often the covered part.

  • Exterior photos of the dam, icicles and snow load, if still present. Note the date and weather.
  • Roof covering condition at the eaves: age, granule loss, prior repairs.
  • Whether ice and water shield is present at the eaves (check at an edge or penetration if you can do it safely).
  • Attic ventilation at the eaves and ridge, and whether soffit vents are blocked.
  • Attic insulation depth and gaps; unsealed hatches, recessed lights or ducts that leak warm air.
  • Interior water path: stains at exterior wall tops, ceiling and insulation damage, with moisture readings.
  • Any signs of earlier leaks at the same spot, which point to a pre-existing condition.

Stay off icy roofs. A drone, a pole camera or a look from the eave on a ladder is usually enough for an ice dam file, and no estimate is worth a fall.

What to watch this winter

  • CPC's monthly ENSO updates and the 6–10 and 8–14 day outlooks. A cold snap reaching the Gulf states is the setup for a Fern-style claim wave.
  • Power outages during ice events in electric-heat regions. Outages are the trigger that turns cold into burst pipes.
  • Heavy rain claims in the South and along the East Coast, which NOAA's outlook makes more likely and which bring their own flood vs water damage coverage questions.

The forecast favors a mild northern winter. Your file notes should be ready for the week it isn't.

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