The major storm cycle has treated many parts of the Andes well, with the first phase delivering up to 1.2 m at Nevados de Chillan. This fell in about twenty-four hours while Valle Nevado and the three valleys (Farellones, La Parva, and El Colorado) received 60 cm. Valle Nevado opened on Friday with bluebird skies and 60 cm of low-density pow. 

The second phase of the storm will continue to bring additional snow to the northern zone on Monday, with some decent additional accumulations, in the 15 to 30 cm range. We could see snow shower activity linger through all zones through Tuesday morning, and maybe even another brief round of showers in the northern zone on Tuesday night before this storm completely wraps up.

Below are the expected accumulations for Monday through Tuesday from the European model.

An upper-level ridge will move over the southern part of the continent on Tuesday and remain there through Thursday, keeping storms to the south. An anomalously strong ridge is expected to then develop off the southern Chilean coast, which will likely keep the next storm's impact predominantly in the central and southern zones. You can see this at the start of the GIF. The models disagree on just how impactful this next storm will be. 

Later in the GIF, you can see the upper-level ridge weaken and move off to the east, while a new ridge forms farther south and west in the southeast Pacific. This would allow the next storm to track farther north into the Andes and bring more significant overall impacts. However, this is in the seven to ten day range, so confidence remains low at this time. 

The ensembles keep the ridge a bit farther east than the deterministic models, which would result in weaker storms that track farther south. This casts further doubt on the impacts of the storms later next week. We will have to give the models a few more days before we can be more confident on these potential storms. 

Next post on Wednesday.

Thanks for reading the South America Daily Snow!

Luke Stone
Forecaster, OpenSnow

NEW: Forecast Range Graphs

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