It may be August, but early indicators are already brewing for what the 2023-24 winter season could look like in Colorado.
At Breckenridge Ski Resort, . Whether it will herald another blockbuster ski season remains to be seen, though one factor is nearly certain: atmospheric patterns are set to change this winter.
鈥淲e are going into what looks to be a strong El Ni帽o season,鈥� National Weather Service meteorologist Bernie Meier said.
El Ni帽o patterns can form when surface temperatures in the equatorial Pacific Ocean (off the coast of South America) rise above average by 0.9 degrees Fahrenheit for three consecutive months, according to Meier.
El Ni帽o pushes the jet stream south and can bring more precipitation and cooler temperatures to southern regions. In Colorado, this can translate to heavier, wetter snow in the southwest, particularly for the San Juan Mountains, as well as the central mountains. In the state鈥檚 northern areas, such as Steamboat Springs, weather may be warmer while snow is dryer, Meier said.
鈥淣ot every year is a great snow producer, but if you look at the history, we tend to do better than not for snowfall with El Ni帽o,鈥� Meier said of the southern and central mountain region.
A shows a greater than 90% chance of an El Ni帽o pattern persisting through the December 2023 and February 2024 winter season across the United States.
The prediction comes after the past three winters saw a La Ni帽a pattern (the inverse of El Ni帽o), according to an August 14 report by meteorologist Alan Smith .
La Ni帽a occurs when the same ocean temperatures fall below average and is defined by wet, cold weather in the north and dryer, warmer weather in the south. According to Smith, the succession of La Ni帽a patterns over the past three years has only happened three times since 1950 鈥� a 鈥渞are occurrence.鈥�
鈥淐onfidence is increasing that we could see a strong El Ni帽o this year,鈥� Smith wrote in his report, adding the last strong El Ni帽o pattern was in 2015-16.
However, neither pattern guarantees an outcome for winter conditions, especially at the local level.
鈥淚t鈥檚 one of the few things that we have any shred of ability to forecast six months in advance,鈥� said OpenSnow founder Joel Gratz. 鈥淛ust because there鈥檚 a correlation, it doesn鈥檛 mean that every year is guaranteed to be that way.鈥�
Last winter鈥檚 La Ni帽a pattern should have been characterized by heavy snowfall in the north and less in the south, but that wasn鈥檛 completely the case in Colorado.
While snowfall continuously blanketed the state鈥檚 northwest, , storms also favored southern mountains, with .
Even the central mountains, which are , received above-average snowfall and .
鈥淚t kind of broke the rule of what you鈥檇 expect last year,鈥� Meier said of the La Ni帽a pattern.
By late last winter, however, the La Ni帽a pattern had begun to phase out, with ocean temperatures beginning to rise in March, Meier said.
鈥淲e鈥檝e almost met the conditions for El Ni帽o already and should carry on into winter and next spring,鈥� he added.
Though a stronger La Ni帽a or El Ni帽o pattern can mean average or above-average snowfall, in some areas there isn鈥檛 a strong correlation between snow and atmospheric patterns, such as around Colorado鈥檚 Continental Divide.
And a 90-day forecast from NOAA shows equal chances for above, below or normal temperature and precipitation, making it anyone鈥檚 guess for how the beginning of ski season will kick-off in the Colorado High Country.
鈥淚鈥檓 curious to see how this is going to play out,鈥� Meier said.
