Remember the Fall’s weather forecast? (Part One)

The fall‑2025 snow forecasts for the western United States promised us almost the same precipitations and temperatures as an average winter for Utah. In reality, it ended up being totally wrong and quite the opposite (no snow and milder temperatures) because the large‑scale climate signals that NOAA (US weather forecast) and the Farmer’s Almanac relied on, behaved totally differently than expected once the season actually arrived.

Even though the sources I’m mentioning were focused on general winter outlooks, they highlighted their key weakness as seasonal forecasts are probabilistic and heavily dependent on ENSO patterns (El Niño-Southern Oscillation). The ENSO cycles are natural, recurring, 2–7 year climate variations involving shifts in tropical Pacific Ocean temperatures and atmospheric circulation. 

These oscillations consist of three phases, El Niño (warm), La Niña (cool), and Neutral, all of which influence global weather, including precipitation, temperature, and hurricane activity, particularly during winter. As it looked into the winter 2025-26, NOAA, our national weather forecasting expected La Niña to continue, with a transition toward neutral conditions sometime in early 2026. 

But apparently the strength, timing, and regional impacts of La Niña vary widely from year to year. In 2025, the pattern weakened earlier and behaved irregularly, which disrupted the typical storm track that brings early‑season snow to the West. This means that even when the broad climate pattern is known, the exact distribution of snowfall was extremely difficult to predict months in advance. 

Our scientists are not talking much about climate change and the increased number of atmospheric rivers. This must be in my own head! There are however additional reasons that we’ll discuss tomorrow...