Every year, during the last week of August to the first week of September, a massive winter storm hits the southern Andes Mountains of Patagonia, blanketing the range with anywhere from one to three meters of snow – 40 to 120 inches! This storm is known by the locals as the Santa Rosa. Right now, she is making her way across the Pacific Ocean to dump massive quantities of snow in the Patagonian peaks of Argentina. This is the ideal time to be skiing and snowboarding in South America!
This year, it looks like we’ll be getting a one-two punch in two waves: the first mild and wet, the second intense, cold, and all out puking. There is one major wave currently pushing through the region the evening of Tuesday, August 25th, into Wednesday, August 26th. This first wave is warmer, wetter and more calm: freezing levels around 2000 meters to start, lowering to around 1600 meters, with winds in the light to moderate category out of the North, Northwest, then West as the first wave makes its exit. The current GFS model weather forecast analysis is advertising around 45 mm (1.8 inches) of water during this first 48-hour period. Snow densities will likely be higher during this first wave, starting somewhere around 12-14%, then dropping to around 10%. This should be good for new snow adhesion to the existing snow surface, an excellent setup for the second round of precipitation. Possible snow totals for first wave = 15-18″.
The true Santa Rosa storm looks to make landfall on Friday, August 28th, and remain in place through Sunday, August 30th. This will be the aforementioned second wave, far more intense than the first: freezing levels around 1600 meters to start, then dropping to 1400 meters as the storm tapers off, with winds in the moderate to strong category, primarily out of the Northwest. The latest GFS solutions are predicting precip totals up to 66 mm (2.6 inches) of water during this second 72-hour period. With copious amounts of moisture and cold temperatures expected, this second wave should drop a deep blanket of Patagonian powder on top of the higher density cushion from the prior first wave of snowfall. This really is a perfect setup for ending the ski season with some stellar powder skiing. Possible snow totals for second wave, the true Santa Rosa = 26-30″.
At a 10% average density, we could be looking at four feet of snow out of these two storm systems! Monday, August 31st, looks like ‘the day’: cold temps and clear skies after the storm moves out. Wrap-around moisture looks to enter the Patagonian region on Tuesday, September 1st, as winds shift to the East. We should pick up only a couple inches of fluff during this event, followed by another beautiful cold, clear day on Wednesday, September 2nd. Watch for the 0° isotherm to make a drastic jump from 200 meters to 3000 meters on Thursday, September 3rd – AVALANCHE WARNING! A small avalanche cycle may be possible between the two waves of storms, on Thursday, August 27th. Then a widespread natural avalanche cycle will likely ensue during the latter half of the second wave, Saturday, August 29th, through Sunday, August 30th, particularly on East and Southeast aspects. Thursday, September 3rd, will surely be a major shed cycle with the sudden rise in temperatures – potential for major slides!
Looking at the extended GFS model forecast, this isn’t the end of it. Cold, wet storms look to continue during the second week of September. We’re looking at a great setup for skiing into October this year, prime time for ski touring in the Andean backcountry and exploring volcano country!
Contact Us or visit our Reservations page to book your trip today, and get some for yourself! Our Andean Backcountry Experience would be the best way to capitalize on the Santa Rosa’s bounty. The predicted best days of the 2015 South American ski season are only a week away! Vamos!