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Portillo ski resort
Tier A — Prime El Niño terrain

South America

Portillo Snow Forecast

91

Outstanding

↗improving

Last Snowfall

Sep 21

today

Past 24 Hours

21cm

Resort reported

Past 48 Hours

25cm

Past 10 Days

55cm

7-Day Forecast

25cm

Snow Depth

255cm

Resort reported
🎿

Powder Days

39

2026 season

☀️

Bluebird Days

3

2026 season

Updated: Sep 21, 10:04 PM•Weather at base: 2,548m
SnowSure™ ScoreAI
91
Outstanding
↑improving

Fresh powder! 21cm in the last 24 hours.

Portillo is experiencing robust conditions with a snow depth of 255cm and 55cm of fresh snow over the past week. The weather is partly cloudy with temperatures around -6°C, making for a pleasant ski experience. With a strong season total of 1021cm, skiers can expect excellent coverage.

AI-generated summary
✓

Depth

255cm depth — excellent coverage.

✓

Recent

In the last 7 days, 55cm of new snow has fallen, including 21cm in the past 24 hours.

✓

Forecast

25cm in the next 7 days.

✓

Historic

This season's snowfall is 241% higher than the 5-year average to date of 423cm.

Data updated Mon, Sep 21, 10:04 PM UTC

Snow Summary

4,222m
ECMWFGFSGEMJMAICONMétéo-Fr

Updated Sep 21, 2026 at 10:04 PM

55cm
24h
25cm
Past 10d
7-Day Forecast
55
Prev10d
2
Now21
0
T22
3
W23
4
T24
13
F25
2
S26
0
S27
Days 8–14 and every model are in Pro.Unlock with Pro
Past
Today
Forecast

Hourly Forecast

21 Mon
-4° / -13°
22 Tue
-3° / -10°
23 Wed
-6° / -8°
24 Thu
-8° / -9°
25 Fri
-6° / -9°
26 Sat
-1° / -10°
27 Sun
-3° / -11°
Days 8–14 and every model are in SnowSure Pro.Unlock with Pro
AMPMNightAMPMNightAMPMNightAMPMNightAMPMNightAMPMNightAMPMNight28 Mon29 Tue30 Wed1 Thu2 Fri3 Sat4 Sun
Conditions☁️⛅⛅🌤️☀️🌤️❄️❄️❄️☁️❄️❄️❄️❄️❄️☁️☁️🌤️☀️🌤️☀️
cloudysome cloudssome cloudsmostly clearclearmostly clearlight snowsnowlight snowcloudylight snowsnowsnowsnowlight snowcloudycloudymostly clearclearmostly clearclear
Summit4,222 mModeled
Temp°C-10°-4°-10°-8°-3°-8°-7°-6°-7°-9°-8°-9°-9°-7°-9°-7°-2°-8°-9°-4°-9°
Feels like°C-15°-8°-15°-12°-5°-12°-11°-11°-12°-15°-14°-14°-14°-12°-14°-12°-5°-13°-14°-7°-14°
Snowcm··0.2··0.51.21.61.6·1.32.22.41.70.9······
Precipmm··0.3··0.71.72.32.3·1.83.23.52.41.3······
Windkm/h10810767898171413121112988997
Mid-mountain3,385 mModeled
Temp°C-4°2°-3°-2°3°-1°0°1°-1°-4°-1°-3°-3°0°-2°0°4°-1°-2°1°-1°
Feels like°C-9°0°-7°-6°1°-5°-4°-3°-4°-8°-4°-7°-7°-4°-7°-5°2°-5°-6°-1°-6°
Snowcm··0.1··0.50.70.51·0.10.30.50.1······0.6
Precipmm··0.1·0.20.81.00.71.5·0.20.40.50.1·····0.40.8
Windkm/h756857756767768868868
Base2,548 mModeled
Temp°C1°7°2°4°8°4°5°6°5°2°5°3°2°6°3°5°9°5°4°7°4°
Feels like°C-3°6°-1°0°7°1°2°3°2°-2°2°-1°-1°2°-1°1°8°0°0°6°0°
Snowcm··0.1··0.50.70.31·0.10.30.50.1·······
Precipmm··0.1·0.20.81.00.71.5·0.20.40.50.1·····0.40.8
Windkm/h756857756767768868868
Humidity%494669566162797077667273595262324744465745
0°C linem—————————————————————
Sunhours

Freeze line is the height where rain turns to snow. Plain: straight from the models. Marked ○: estimated from temperature. Sun is hours of actual sunshine, not day length; blank means we have no reading.

Forecast Range · SnowSure Pro

Every model for Portillo, side by side for 14 days

Where the models agree, where they split, and which one has been most accurate here. Free for 14 days, then yearly.

Unlock with Pro

SnowSure™ blend — verified model weighting

The black line is not a simple average. For Portillo (andes), we combine seven global weather models using weights learned from daily forecast verification — comparing each model's prediction to measured snowfall (SNOTEL, resort reports, ERA5).

  • 1.Horizon buckets: days 1–3, 4–7, and 8–14 each get separate weights — short-range skill differs from long-range.
  • 2.Regional calibration: weights come from verified error in this geography (Rockies, Alps, Japan, etc.), recalculated weekly.
  • 3.Ground truth only: we never grade a forecast against another model — only against measured snow.

Building verification history for this resort.

How we verify forecasts →

Snowfall Forecast Maps

Andes (Chile & Argentina) region

El Niño Outlook · Winter 2026

Portillo El Niño rank & forecast

Portillo ranks #2 of 488 SnowSure resorts — Tier A, +84% in strong El Niño winters.

Tier A — Prime El Niño terrain: Historically snowed much more than normal in strong El Niño winters (≥ +8% vs this resort’s own 30-year average).

#2 of 488Tier A — Prime El Niño terrain

Strong-event signal: +84% vs this resort's 30-yr avg

In the three strongest El Niño winters on record ('97-98, '15-16, '23-24), Portillo averaged +84% versus its own 30-year snowfall baseline. The pattern has historically been a friend here. With a record-strength event forecast for winter 2026, Portillo sits on the favorable side of the ledger. Analog winters: '97-98 +98%, '15-16 +18%, '23-24 +136%. A pattern, not a promise.

'97-98 +98%'15-16 +18%'23-24 +136%

In-season scorecard

Predicted signal

+84%

Measured to date

+245%

Season total

1,021 cm

Vs predicted

+161%

Predicted signal vs measured season-to-date against this resort's own climatology.

Signal = average snowfall in the three strongest El Niño winters since 1996 ('97-98, '15-16, '23-24) vs this resort's own 30-year ERA5 baseline. n=3 — a lean, not a law. Updated monthly against measured snowfall Dec–Mar.

Full El Niño report →

ENSO seasonal analog

History · not a forecast

In 6 past El Niño winters at Portillo, ERA5 season snowfall median was 509 cm (200 in), about 57% above this resort’s long-term median. This is a historical analog from reanalysis — not a prediction of this winter’s storm track.

Prevailing ONI

El Niño

JJA 2026 · ANOM +1.8°C

Analog season median

509cm

6 El Niño winters · 57% above median

All-season median

324cm

Across 31 ERA5 seasons (2026)

PhaseSeasonsMedianp25–p75Recent analogs
El Niñocurrent6509cm417cm – 658cm2026, 2023, 2015, 2009, 2002, 1997
La Niña4251cm180cm – 306cm2022, 2010, 1999, 1998
ENSO-neutral21287cm243cm – 390cm2025, 2024, 2021, 2020, 2019, 2018

Season snowfall from Open-Meteo ERA5 reanalysis (~9 km). ENSO phase from NOAA CPC Oceanic Niño Index. Relative phase differences are more trustworthy than absolute cm totals. Source: NOAA CPC Oceanic Niño Index + Open-Meteo ERA5 via SnowSure season archive.

Local Reports

0 reports

How accurate is this forecast?

We verify every forecast against what actually fell — see the model-by-model results.

→

Frequently asked questions about Portillo

How much snow is Portillo getting this week?
The SnowSure™ blend forecasts about 25 cm (10 in) of snow at Portillo over the next 7 days.
What is the 14-day snow forecast for Portillo?
The full 14-day forecast for Portillo — the SnowSure™ blend and every model we track, day by day — is part of SnowSure Pro. The first 7 days are free on this page.
How accurate are SnowSure forecasts for Portillo?
We verify every forecast against what actually fell and publish the results — see our forecast verification pages for model-by-model accuracy, updated continuously.