Ocean temperatures in the central and eastern Pacific are on the move and from that it's possible to extrapolate the likelihood of a snowy ski season 2016-17 in Western North America – kind of.
The region's weather is dominated by two long standing weather phenomena - El Niño and La Niña, one or the other of which ends to dominate for a year or longer at a time.
This past year has seen a particularly 'strong' El Niño, dubbed the 'Godzilla El Niño' which has brought large amounts of precipitation to the Western US, falling as snow in many ski areas. The biggest snowfall totalled nearly 18 metres at Alyeska in Alaska whilst ski areas like Mammoth and Squaw Valley are sitting on bases metres deep as we enter May and plan to stay open at least another month, possibly longer. Most importantly it also ended a five year drought in California.
Resorts in South America are now hoping that they'll also benefit from the Godzilla El Niño and a snowy 2016 season has been forecast with heavy snow already reported two months before the season is due to start in Chile and Argentina.
However the National Oceanic and Atmospheric Administration (NOAA) in the US say things are changing and that last month the sea temperature in the crucial area OF THE Pacific dropped by nearly half a degree Celcius. This signals, they belief, a flip to La Niña conditions.
It can be confusing because the marketing departments of ski resorts in the region tend to say both La Niña and El Niño can mean heavy snow, but what it seems to be is that a 'strong' La Niña or El Niño can mean heavy snow, whilst a weak one of either tends to be a bit lacklustre on the snowfall front.
Historically though a strong La Niña tends to follow a strong El Niño and the NOAA are saying that the 2016-17 La Niña should be a strong one.
La Niña is associated with colder weather than El Niño raising hopes of still more snow than this winter, indeed the world record snowfall of 28 metres in one season reported by Mt Baker in Washington state in the late 1990s happened in a strong La Niña winter.
The extent and in the influence of the Pacific weather patterns is very complex, largely unpredictable and difficult to measure beyond the Western sides of North and South America. El Niño tends to be associated with warmer, wetter weather and Japanese ski areas as well as those further East in North America had either less good or fairly terrible winter for snowfall with conditions too warm and wet in the past winter.
However attempts by British tabloids last autumn when the strong El Niño was reported to suggest that excess snowfall would travel across the Atlantic to create an Armageddon-like winter weather in Britain and Europe in 2015-16 proved 100% wrong.
http://www.express.co.uk/news/weather/613168/UK-long-range-winter-weather-forecast-2015-snow
http://www.telegraph.co.uk/news/weather/11999259/British-winter-could-feel-longer-and-colder-because-of-El-Nino.html
However that's not stopped them already forecasting similar conditions for next winter in the UK:
http://www.express.co.uk/news/weather/647010/Weather-UK-El-Nino-La-Nina-warning-UK-storms