South America Snow Forecast: Up to 45 cm through Thursday

Snowfall forecast map — Credit: NOAA/NCEP GFS

This South America snow forecast keeps an ongoing storm at center stage through Thursday afternoon, then shifts the heaviest snow to the southern Andes from Friday into Sunday. Nevados de Chillán leads the near term with 36-45 cm still to come, while Corralco, Las Leñas, and the high resorts of central Chile also add meaningful totals. A colder weekend wave could bring another 50-80 cm to Corralco and 50-70 cm to Nevados de Chillán, accompanied by powerful ridge winds. Confidence is highest from Wednesday afternoon, August 5, through Thursday afternoon, August 6; confidence drops for the weekend distribution and falls further next week.

The current wave continues Wednesday night and winds down during Thursday, rather than beginning anew. The models converge on the taper and on snow levels staying mainly between 1,200-2,200 meters in central Chile and 600-1,500 meters from Chillán south, below most lift-served terrain. They also converge on the greatest intensity at Nevados de Chillán and Corralco, but diverge more on the exact amount at Las Leñas. Nevados starts with dense snow near 6-10:1 SLR before improving toward 10-14:1, while 11-15:1 farther north favors moderate to occasionally light snow. Peak-wind forecasts diverge, but most support 60-90 km/h gusts around exposed central and Chillán ridges, enough to cause lift holds where terrain is operating.

A second, colder wave reaches northern Patagonia on Friday and lasts into Sunday, with the most consistent signal at Corralco and Nevados de Chillán. The models converge on Friday timing, a Sunday taper, and very low snow levels of roughly 0-1,200 meters, but they diverge on intensity at Corralco. A conservative expectation is 50-80 cm there and 50-70 cm at Nevados de Chillán, with 15-40 cm around Chapelco and Cerro Catedral, 5-30 cm at Las Leñas, 5-10 cm at Cerro Castor, and generally 0-10 cm in central Chile. Snow trends moderate to light at roughly 10-16:1 SLR. Wind guidance differs on the exact peak and location, yet converges on disruptive 70-110 km/h ridge gusts across Patagonia, making upper-lift interruptions likely.

From Monday through Wednesday, model agreement breaks down as a third wave favors the central Andes while Patagonia turns more showery. Timing and intensity diverge sharply, with a realistic range of another 10-30 cm around Las Leñas, 5-15 cm at the high central Chile resorts, and 5-20 cm from Chapelco to Cerro Catedral. Timing differs by about a day, snow-level solutions spread from 1,800-2,900 meters in central Chile, and wind forecasts range from manageable to disruptive, so the skiing outcome is far less certain. From Thursday through Saturday, the remaining signal is weak and inconsistent, generally 0-10 cm, with higher snow levels and only brief chances for refreshes.