Long range forecasting: is it useful, or useless?

SEATTLE — We’ve all seen the seasonal outlooks coming across our social media feeds with graphics announcing a “warmer than usual autumn” or proclamations urging you to prepare for “an extra snowy winter ahead.”

But how accurate are these longer-range forecasts?

KOMO’s Chief Meteorologist Shannon O’Donnell is a bit of a skeptic. She’s found that these seasonal outlooks are wrong as often as they are correct. Shannon also argues that they aren’t particularly helpful even if they are correct.

For instance, if it does turn out a bit wetter than normal, is that because we’ve battled several atmospheric rivers during a season that was otherwise punctuated by long, dry stretches? Or does it suggest that we’ll see three months of constant gray and drizzle? Both scenarios can result in a “wetter than normal” outcome, but they are very different lived experiences.

Nick Bond is the Washington State Climatologist, Emeritus. He coined the term “the Blob” over a decade ago to call attention to warm temperature anomalies in the Pacific. Mr. Bond is an expert in the climate of the Pacific Northwest, and believes that the seasonal forecasts have come a long way in the decades that he has been studying our region.

KOMO Meteorologist George Waldenberger contends that while the models might not yet be perfect, we need to start somewhere, and that the information they reveal is still useful in seasonal planning, especially in industries that count on considerations of temperature and precipitation such as our ski resorts or farming groups.

Watch the video above or on the KOMO News YouTube page for a special discussion about the merits and pitfalls of seasonal and longer range forecasting of the Pacific Northwest, and beyond.

Follow Shannon O’Donnell and George Waldenberger on social media. See your full forecast here.