Portillo CLLIVE
80% of simulated seasons land between 289" and 569". 45% of this season is already locked in by observed snowfall and the 16-day forecast — the simulation only fills in the rest.
10,000 simulated 2026 seasonsENSO-weighted resampling of 36 real seasons (1990–2026) at Portillo, tilted by the live seasonal outlook, anchored on snow already on the ground
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 season is simulated by resampling Portillo'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 strongest ENSO-snow teleconnection of any ski region on Earth: El Niño parks the subtropical jet over 30-37°S and hammers the high Andes (Masiokas et al. 2006). Portillo averages ~+45% snowfall in warm-ENSO seasons; storms are characteristically back-loaded into July-September. Applied as a +16% tilt at partial weight.
45% of the season window is now locked in by observed snowfall and the blended near-term forecast (64" over the next 16 days). Each analog season contributes only what it delivered outside the known windows in its own calendar.
The regional readAndes · from the 2026-27 outlook
This is El Niño's flagship ski trade: with Niño3.4 possibly reaching +2.0°C, the subtropical jet should park over central Chile and hammer the 30-37°S Andes through late winter — Portillo averages roughly +45% snowfall in warm-ENSO seasons (Masiokas et al. 2006; bestsnow.net). The dry, slow June 2026 start fits the pattern rather than breaking it: 1997 and 2015 also began quietly before multi-meter July-September storm cycles produced some of the deepest Portillo bases on record. August and September should be the payoff months. If you hold a multi-resort pass, this is the hemisphere to spend it in.
Month by monthENSO-conditioned analog medians vs a typical month — when this season should deliver
Prime window: Jun–Jul — the deepest contiguous stretch of the conditioned season. Aim the trip there.
The analog poolEvery season since 1990 at Portillo (ERA5, calibrated to the resort's reported average), colored by ENSO phase
Next 16 days, model by modelDaily snowfall (inches) at mid-mountain from four global models — fetched 2026-07-10
| Model | 7/10 | 7/11 | 7/12 | 7/13 | 7/14 | 7/15 | 7/16 | 7/17 | 7/18 | 7/19 | 7/20 | 7/21 | 7/22 | 7/23 | 7/24 | 7/25 | Total |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| GFS (NOAA) | 3.6 | 0.7 | — | — | 1.5 | 1.0 | 0.3 | 2.6 | 10.5 | 4.1 | 0.9 | — | — | — | — | — | 25.3" |
| ECMWF IFS | 4.9 | 1.5 | — | — | — | 0.2 | 8.8 | 14.2 | 18.9 | 8.9 | 6.9 | 0.6 | 0.1 | 0.1 | 0.8 | — | 65.9" |
| ICON (DWD) | 2.2 | — | — | — | — | 5.3 | 8.7 | 33.8 | — | — | — | — | — | — | — | — | 50.0" |
| GEM (Canada) | 23.6 | 0.9 | — | — | 0.1 | 8.0 | 24.3 | 18.6 | 6.3 | 4.2 | — | — | — | — | — | — | 85.9" |
| PassCast blend | 8.6 | 0.8 | — | — | 0.4 | 3.6 | 10.5 | 17.3 | 11.9 | 5.7 | 3.9 | 0.3 | — | — | 0.4 | — | 63.5" |
Pass math for Portillo
Portillo 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.