Willamette Pass OR
80% of simulated seasons land between 110" and 395". Reseeded daily as ENSO observations, CPC outlooks, and SEAS5 runs update.
10,000 simulated 2026-27 seasonsENSO-weighted resampling of 36 real seasons (1990–2026) at Willamette Pass, tilted by the live seasonal outlook
Highlighted bars span the middle half of outcomes (P25–P75). The yellow dashed line is a typical season — the median of the last 36 at this mountain.
What's driving this forecast
The 2026-27 season is simulated by resampling Willamette Pass's historical seasons weighted toward El Niño analog years. NOAA CPC El Niño Advisory (June 11, 2026): El Niño conditions are present and expected to strengthen into winter 2026-27, with a 63% chance of a very strong event (Niño3.4 ≥ +2.0°C) during Nov-Jan. CPC DJF strength odds: very strong 46%, strong 33%, moderate 16%. IRI (June 22) concurs at 98% El Niño for DJF.
The most reliable ENSO ski signal in the US: La Niña winters run ~115-125% of normal in the Cascades; El Niño is 'the great snowfall suppressor' (NOAA) with warmer storms and higher snow levels. Applied as a -7% tilt at partial weight.
The 51-member SEAS5 seasonal forecast puts Nov–Jan snowfall at this grid point at 90% of its ERA5 normal (ensemble mean 153", spread 92–211"). Applied as a -3% tilt — experimental, heavily shrunk and clamped because seasonal models and reanalysis have different biases.
Day-to-day weather models have no skill this far out, so the near-term forecast contributes 0% weight today. The simulation leans entirely on ENSO-conditioned climatology — exactly what an honest seasonal outlook should do in summer. Weighting shifts toward live forecasts as opening day approaches.
The regional readPNW · from the 2026-27 outlook
No US region has more to lose from a strong El Niño: the jet dives south and the Cascades marinate in mild Pacific air. The analogs are grim — 2023-24 delivered one of the worst Cascade seasons in memory with mid-winter rain to the summits, and 1997-98 ran well below normal; 2015-16 was the merciful near-normal exception. Odds strongly favor below-average snowfall and elevated freezing levels, hitting low-elevation terrain hardest. Book March, not December.
Month by monthENSO-conditioned analog medians vs a typical month — when this season should deliver
Prime window: Dec–Jan — the deepest contiguous stretch of the conditioned season. Aim the trip there.
The analog poolEvery season since 1990 at Willamette Pass (ERA5, calibrated to the resort's reported average), colored by ENSO phase
Pass math for Willamette Pass
Willamette Pass isn't on a multi-resort pass — but you can still see what a season here is worth.
No multi-resort pass covers these mountains — window tickets are the play.
Sources: ERA5 reanalysis & multi-model forecasts via Open-Meteo · NOAA CPC ONI, ENSO advisory & seasonal outlook · ECMWF SEAS5 · pass prices verified July 2026. See methodology for the honest fine print.