The weather-roiling La Niña that forecasters have been predicting for months will likely arrive late and in a weakened form, limiting its impact and allowing other climate patterns to hold more

The National Weather Service’s Climate Prediction Center has released updated guidance on the possibility of a La Niña weather pattern emerging later this year, and it could have impacts on the fall and winter weather that Chicago experiences.

The delayed onset means La Niña will have a weaker atmospheric effect, allowing other weather patterns, such as the North Atlantic Oscillation, to have more sway. This pattern could play a critical role in shaping winter conditions in the US Northeast, where it might determine whether the region experiences a mild or severe winter.

The Pacific Northwest and Intermountain West are in for a doozy of a winter if Chris Tomer's predictions are realized.