As the first sprinkles of snow fell on Western Slope mountains this week, meteorologists predicted an El Niño event to hit the United States this winter.
That could mean anything and everything for Colorado.
“Skiers and snowboarders especially look at snowfall history in the Sierra Nevadas and Pacific Northwest and think that El Niño is a huge snow producer for the entire West,” said Noah Molotch, a professor of geography at the University of Colorado Boulder and the director of the university’s Center for Water, Earth Science and Technology. “It can be, but statistically we have no evidence to say that it will.”
Last week, the National Oceanic and Atmospheric Administration predicted a 70 percent chance of an El Niño for the 2018-19 winter. Tom Di Liberto, a meteorologist with NOAA, said it’s too early to say with confidence the strength of the climate variation event.
“As we move into the fall, our models and the ocean-atmosphere conditions will be clearer and we can better determine how strong the El Niño will be,” he said. ”The stronger the El Niño, the more consistent with the general pattern of an El Niño this winter will be.”
The Old Farmer’s Almanac predicted a weak El Niño for this winter, with above-normal temperatures almost everywhere in the U.S. except in the Southwest, where a colder-than-normal season is predicted. The Almanac’s weather map shows parts of the state experiencing warm and dry, mild and snow, warm and wet, and cold and wet conditions.
RELATED: More Colorado News
During El Niño events, a strong jet stream and storm track across the southern part of the U.S., and less stormy and milder-than-average conditions across the north. This means an “exceptionally” stormy winter in California and the southern U.S., NOAA wrote.
Though the 2016-17 winter was not considered an El Niño year, large plumes of moisture that resembled those that frequent northern California during El Niño years dropped feet of snow on the Sierra Nevada mountains, Molotch said. Deemed a “snowpocolypse” event, a storm during the first week of January dropped nearly 3 feet of snow in 24 hours and 7 feet in seven days on Squaw Valley Ski Resort, the ski resort tweeted Jan. 5, 2017.
Colorado straddles the jet stream as it runs across the northern and southern tiers of the United States, and scientists have not been able to find corollary data between El Niño events and the snow conditions in Colorado.
“In general, I don’t tend to make a whole lot out of El Niño predictions in terms of snow conditions in Colorado because we’re right in that inflection point,” Molotch said.
He continued, “You also have to remember that the Sierras, the mountains in the Pacific Northwest and others in the western Rockies are really efficient in squeezing snow out of these storm systems. By the time those storms get to Colorado, you don’t have a significant amount of snowfall.”
Even if Colorado’s winter definitively sways with the northern or southern jet stream, the characteristics ascribed to El Niño events are influenced by other climactic and weather elements that are unique to a specific winter season.
”We don’t necessarily see storms moving to the same places and in the same direction winter-to-winter in a normal year, which is also the case for an El Niño year,” Di Liberto said. “Every winter has other factors that can tweak the characteristics of a general El Niño.”
Joel Gratz, a meteorologist with the snow forecasting site OpenSnow, recommended that skiers looking to plan their trips months in advance “focus on factors that you can control, like exploring new terrain and activities, ease of travel, and being with friends and family.”
RELATED: More Colorado News
‘If your main goal is to enjoy deep, fresh powder, you’ll need to watch the forecast closely through the season,” he wrote.
As Colorado awaits its uncertain snow season, the state is expected to remain in drought through the end of November with above-average temperaturesThe seasonal drought outlook for Aug. 16 through Nov. 30 produced by the Climate Prediction center forecast drought to persist but improve in the southern part of the state, but to persist without improvement in the central and northwest corner.
El Paso County — which currently is a mosaic of abnormally dry, moderate drought and severe drought — sits in the latter of the two predictions.
What We Believe
We are driven by our deep respect for our environment, and our passionate commitment to sustainable tourism and conservation. We believe in the right for everyone - from all backgrounds and cultures - to enjoy our natural world, and we believe that we must all do so responsibly. Learn More