South America Snow Forecast: Up to 3 Meters by Monday

Snowfall forecast map — Credit: NOAA/NCEP GFS

The South America snow forecast keeps much of the Andes active through Monday, with the largest reload aimed at Nevados de Chillán and substantial totals spreading north through the central Andes. Snow already underway continues early this week, a broader storm cycle builds from Thursday night into Friday, and wind may limit exposed lifts during the heaviest periods. Portillo remains fully closed; current reports show lift-served operations at every other resort, though several have partial terrain, so daily lift status will matter as snow and wind intensify.

Snow already underway over Las Leñas, Cerro Catedral, La Parva, Valle Nevado, Corralco, Nevados de Chillán, and El Colorado continues in waves through Tuesday or Wednesday. The individual models converge on the early-week timing and show Nevados de Chillán and Corralco receiving the most persistent snow, but diverge on the lighter central-resort amounts and the exact taper. Central Andes SLRs generally run 8-14:1, yielding dense to moderate snow, while ratios near 3-10:1 at Nevados and Corralco signal heavier, wetter accumulation. Snow levels hover near 1,700 meters in the south and northern Patagonia and occasionally climb toward 2,800 meters in central Chile, favoring upper-mountain quality. Wind forecasts converge on disruptive exposure at Nevados and Corralco but vary more farther north.

A broader reload organizes Thursday night into Friday and remains active through Monday, with the deepest cycle focused on Nevados de Chillán and another major round from Corralco north through the central Andes. All individual models converge on the broad timing and snowy footprint but diverge sharply on intensity, brief snow-level rises, and wind impacts. Central Andes snowfall should carry mostly 10-16:1 SLRs and improve as levels fall below 2,000 meters, though embedded warmer pulses may push levels toward 3,000 meters and make lower slopes denser. Northern Patagonia stays mostly dense to moderate, with snow levels near or above lower elevations at times. The central-Andes wind spread runs from manageable to lift-disruptive, while agreement is stronger for significant exposed-ridge impacts at Nevados and Corralco. Confidence in timing and snowfall detail is highest from Monday afternoon, July 27, through Monday evening, August 3.

After Monday evening, the forecast becomes much less settled. For Tuesday through Thursday, AIFS and GFS keep broad snow going across the main Andes while ECMWF is mainly dry there, so the signal is real but highly uncertain. A conservative read is another 20-50 cm across the central and southern Andes and northern Patagonia, with locally higher potential near Nevados de Chillán if the snowier solutions verify; Cerro Castor may see 5-15 cm. Snow levels and wind impacts are too divergent to specify at that lead time. Portillo’s full closure limits any immediate lift-served benefit there, and partial operations elsewhere could become more restricted during the heavier snow and stronger winds.