In OpenSnow forecaster Alan Smith’s winter preview, he said a potentially historic super El Niño pattern could tip odds toward above-average snowfall for Park City.
Smith said an El Niño year develops when sea surface temperatures are warmer than usual in the central and eastern tropical Pacific Ocean.
“And in El Niño like this year, where you hear the phrase ‘strong’ or ‘super’ El Niño, that means that temperatures are well above average in this region,” he said on KPCW's "Local News Hour" Aug. 7.
The National Weather Service said El Niño is expected to strengthen through the end of the year, with a 90% chance it becomes very strong between October and December.
While Utah typically sits in the “equal chances” zone for these years, he said the strongest historical El Niño events show a clearer snowy signal for Utah and other western states.
“Looking at these stronger episodes, it has a pretty good signal for Utah as well,” he said. “And while it's not a guarantee, every episode is different. Just taking all the data from the past and looking at it, it does tilt the odds in favor of above-average snowfall.”
Smith noted the strongest signal for Utah comes later in the season from January to March. His model on OpenSnow found Park City historically has one of the strongest correlations with above-normal snowfall during strong El Niño events.
But the forecast is far from certain. Strong El Niño winters also tend to be warmer than normal. OpenSnow cautions that seasonal forecasts carry significant uncertainty.
Past El Niño seasons have been a hit-or-miss with storms bringing more than 600 inches during the 1983-1984 season, the state’s second-snowiest season on record, or barely reaching the 400-inch mark at the Alta snow stake like the 2015-2016 season.
