El Niño in the Pacific Northwest: A Drier, Warmer Winter and the Snowpack Problem

The Pacific Northwest sits on the losing side of the El Niño storm-track trade. The same shifted jet stream that aims atmospheric rivers at California takes them away from Washington and Oregon — and with El Niño declared in June 2026 and NOAA's odds of a strong-or-stronger event near 90%, the coming winter leans warm and dry.

Lean is the operative word. The Northwest signal is real but softer than California's, and it fails more often. Treat what follows as loaded probabilities, not a schedule.

The mechanism: a storm track that moves south

In a neutral winter, the Pacific jet delivers a steady train of storms into the Northwest coast, and the Cascades wring the moisture out as snow. El Niño changes the delivery route. The subtropical jet strengthens and the main storm track shifts south, so more systems make landfall in California and fewer in the Northwest.

Warmth is the second half of the problem, and in this region it is the sharper half. El Niño winters run milder, which raises freezing levels — and much of the Cascades' snow falls at elevations where a degree or two decides rain versus snow. A winter can land near-normal precipitation and still finish with a poor snowpack because too much of it fell as rain.

What the analogs did

1997-98, the strongest event of the modern record, produced a mild winter with well-below-normal snowpack across much of the region.

2015-16 is the more instructive case. Precipitation was not unusually low — parts of the region were near normal — but temperatures ran warm and the snow line sat high all winter. The result was the "snow drought" pattern: wet mountains, thin snow. It is the cleanest demonstration that in the Northwest the temperature signal can do the damage on its own.

The events differed enough that the honest summary is a range: below-normal snowpack is the way to bet, with the size of the deficit set by how warm the winter runs.

What it means, sector by sector

Water and hydropower. Snowpack is storage. A thin April snowpack means weaker late-summer streamflow in 2027, tighter hydro margins and warmer rivers when salmon need cold water. The bill for an El Niño winter here arrives the following August.

Ski areas. Pass-level areas carry the most risk, since they live closest to the rain-snow line. Higher terrain fares better. Both analog winters were hard on the industry, 2015-16 especially at lower elevations.

Flood risk does not disappear. Fewer storms is not zero storms, and warm atmospheric rivers falling on snowpack are the region's classic flood recipe. El Niño reduces the count and raises the share arriving warm.

What to watch

Freezing levels in the incoming storms matter more than storm counts — that is the variable the analogs punish. The live dashboard carries the current event state, and the subsurface heat content on the forecast page is the best early hint of whether the event still has fuel heading into the heart of winter.

For operational forecasts, river and avalanche conditions, rely on the NWS offices and the Northwest River Forecast Center — this site tracks the driver, not the day-to-day weather.