South America Snow Forecast: Meter-Plus through Sunday

Snowfall forecast map — Credit: NOAA/NCEP GFS

This South America snow forecast keeps an ongoing storm active in waves through Sunday, with the deepest accumulation aimed at the south-central Andes. Confidence is strongest from Sunday afternoon, August 2, through Sunday evening, August 9, the period covered by the totals below. Nevados de Chillán and Corralco should finish well above a meter, while lighter but still useful refreshes spread north and south. Portillo remains closed, while Las Leñas, El Colorado, Nevados de Chillán, and Cerro Castor have partial terrain, so fresh snow will not always translate directly into lift-served access.

The storm already in progress continues through Monday before most areas see a taper or short break Tuesday. The individual models converge on that timing and on relatively high initial snow levels, but diverge on intensity around Portillo and Las Leñas and on the strength of exposed-ridge winds. Snow levels generally run from 2,200-3,100 meters in central Chile and 1,000-2,100 meters in northern Patagonia, allowing some wet or mixed precipitation near lower slopes before colder air settles in. Dense snow dominates with roughly 7:1 to 10:1 SLRs. Gust projections range from about 30-75 km/h, leaving upper-mountain lift delays possible.

A broader reload develops from Wednesday into Friday morning, with the most consistent signal from Las Leñas south through the lake district. The individual models converge on the arrival and on falling snow levels, but diverge substantially on snowfall intensity and wind impacts. Snow levels lower toward 700-2,500 meters in the central Andes and 300-1,900 meters across northern Patagonia, improving coverage down the mountains. Snow quality also improves toward moderate 10:1 to 14:1 SLRs. Several solutions produce exposed gusts of 70-110 km/h, while others are much calmer, so upper lifts may have intermittent operating windows even where snowfall verifies.

The coldest and potentially deepest pulse arrives Friday through Sunday, especially at Corralco and Nevados de Chillán. The individual models converge on timing and low snow levels there, supporting totals of 105-171 cm and 109-177 cm, respectively, but still diverge on peak intensity and whether ridge gusts approach 80-120 km/h. Snow levels fall mostly below 1,100 meters in Patagonia, and 13:1 to 19:1 SLRs favor lighter snow. Central Chile and Las Leñas have wider snowfall spread. From Monday through Wednesday, guidance diverges sharply, with a conservative 5-15 cm signal where additional snow develops, but dry outcomes are still plausible.