South America Snow Forecast: Up to 50 cm through Sunday

Snowfall forecast map — Credit: NOAA/NCEP GFS

This South America snow forecast keeps the Andes active, with the ongoing storm carrying dense snow and strong winds into Sunday before colder systems reload next week. The most dependable detail runs from Friday afternoon through Sunday morning, when Portillo and Valle Nevado lead the snowfall totals. Portillo remains closed, and partial operations at several other mountains plus strong winds mean lift availability may change quickly. The longer-range pattern stays snowy, but timing and amounts become less certain after Sunday.

The individual models converge on the current storm continuing through Saturday and winding down by Sunday morning, but they diverge sharply on intensity while agreeing that snow levels stay relatively high and the strongest winds focus on Chillán, Corralco, and northern Patagonia. Confidence is highest from Friday afternoon, July 24, through Sunday morning, July 26. During snowfall, snow levels hold near 2,300 to 3,000 meters in the central Andes, 1,000 to 1,800 meters around Chapelco and Catedral, and 1,600 to 2,100 meters near Nevados de Chillán and Corralco. SLRs mostly run 4-10:1, favoring heavy, dense snow, while gusts may reach 60-90 km/h in the southern volcanoes and 40-70 km/h in Patagonia. Portillo’s closure keeps its accumulation off limits to lift-served skiing for now.

A colder reload develops Sunday night through Wednesday morning, with a conservative 20-50 cm possible in the northern and central Andes, 20-40 cm around Chapelco and Catedral, and 30-70 cm around Nevados de Chillán and Corralco. The models converge on the broad arrival and falling snow levels, but diverge on intensity and on the timing of the strongest gusts. Snow levels should drop toward 1,500 to 2,300 meters in the central Andes and below 1,500 meters farther south. SLRs improve toward 10-14:1 in the colder phases, so snow quality should become less dense. Peak gust forecasts span 60-100 km/h in the southern storm belt, leaving another period of likely lift disruption. Because this falls outside the most dependable period, those amounts are broad potential rather than commitments.

From Thursday through Monday, August 3, the models diverge further on timing and intensity but retain a credible signal for another 50-100 cm across much of the central Andes and the Chillán-Corralco corridor, with 15-40 cm around Chapelco and Catedral. Agreement is weaker on snow-level rebounds and wind impacts, so exact powder quality and lift exposure remain speculative. The wettest guidance at Nevados de Chillán appears to be an outlier, making the conservative regional estimate more useful than the upper envelope. Cerro Castor largely misses the first two systems, then has a minor and much more tentative snow signal around next weekend. A clean dry break is not strongly supported, but the spacing of the pulses remains uncertain.