SnowBrains Forecast: Multi-Wave Storm Targets South America through Monday

The South America snow forecast turns active Monday night, with repeated waves capable of delivering 143-261 cm at Nevados de Chillán by Monday morning. The Santiago-area resorts, Portillo, Las Leñas, and northern Patagonia also receive substantial refreshes, while Cerro Castor stays on the fringe. Snow begins dense and wind-affected before trending lighter later in the week. Confidence is strongest from Monday afternoon, August 24, through Monday morning, August 31. Cerro Castor’s current mountain report shows its lifts closed, so the light accumulation there is unlikely to change lift-served options without an operational update.

Snow develops over the south-central Andes Monday evening, then spreads into the central Andes overnight and Tuesday. The individual models converge on a widespread Tuesday-Wednesday snow period and on lift-impacting wind, but they diverge on the central-Andes onset by roughly half a day, peak intensity, and snow-level height. Snow levels range from about 1,100-3,000 meters in the central Andes and 900-2,000 meters farther south, favoring upper-mountain snow with wetter precipitation near some lower bases. SLRs of 6-10 indicate very dense to dense snow. Exposed gusts of 60-110 km/h could slow or suspend upper lifts during the strongest bursts.

Snow briefly eases in places Thursday, but another organized pulse crosses the mainland resorts Thursday into Friday. The individual models generally converge on renewed snowfall timing and a drop in snow levels, while diverging on intensity, the snow-level floor, and the severity of wind impacts. One solution is notably weaker in the central Andes. Snow levels span roughly 700-2,500 meters, lowest in northern Patagonia, with exposed gusts generally 50-90 km/h. Central-Andes SLRs improve to 11-14, producing moderate to locally light snow, while 8-10 SLRs farther south keep the snow denser. Periodic lift holds remain possible where ridge winds peak.

A final weekend reload should taper Monday morning, while a separate Tuesday-Wednesday southern wave could add a speculative 5-20 cm. Through Sunday, the individual models converge on continued mainland snowfall and lower snow levels, but diverge on the exact peak timing, localized intensity, snow-level floor, and wind impacts. The central Andes trend toward 12-16 SLRs, so the later snow should ski lighter, while the southern Andes remain closer to 9-12. After Monday morning, the guidance splits sharply: two longer-range solutions generate meaningful snow from Nevados de Chillán through Corralco and northern Patagonia, while the others are much lighter. Confidence drops quickly for that separate wave.

South America Snow Forecast Resort Totals (Mon Aug 24 – Mon Aug 31)

• Nevados de Chillán – 143-261 cm
• Corralco – 92-164 cm
• Las Leñas – 86-148 cm
• Portillo – 75-135 cm
• Valle Nevado – 69-127 cm
• El Colorado – 58-108 cm
• Cerro Catedral – 62-102 cm
• La Parva – 55-102 cm
• Chapelco – 48-81 cm
• Cerro Castor – 3-6 cm