It’s mixed news for the likelihood of heavy snowfall this winter in North America’s with the news of a La Niña winter being “70-80% Likely” according to the National Oceanic and Atmospheric Administration in the US.

La Niña conditions alternate with El Nino and are used to describe conditions over the Pacific which tend to impact climate for many months.  A current rapid cooling of the Pacific means it is very likely it’ll be a La Niña winter.

Typically La Niña is good news for heavy snowfall in the Pacific Northwest region of North America, as far inland as Jackson Hole, Wyoming, but further south it can bring drier conditions. El Nino tends to bring more precipitation to more southerly latitudes, but that’s not always the case.

On top of the La Niña/El Nino factor the NOAA is predicting above-normal temperatures and drought conditions continuing across Southwestern North America for the remainder of the year.

Over on the East Coast though, the forecast is for a colder, snowier winter than the average.

Ski areas on North America’s West Coast expect to open from early-November with Mt Rose by Lake Tahoe one of the first, targeting the 6th of the month, Heavenly and Northstar the 19th and Palisades Tahoe (formerly Squaw Valley) the 24th.  Resorts have already reported their first snowfall on higher peaks.  The region has seen some early snowfall over the past few days – Mammoth is pictured at the weekend.