Columbia River Bar: traffic drop — -63% vs 83-day median

Traffic through Columbia River Bar has contracted sharply to 28 transits in the past 24 hours, representing a 63% decline against the 83-day median of 76, per ChartNav's monitor. The zone typically experiences swings of roughly 25% around its baseline, making this drop significant. The bar saw volatile activity through late August and early September, with transits surging to 136–156 on September 5–6 before reversing course. Current readings fall well below normal patterns. The cause remains undetermined; ChartNav flags this as a data signal requiring corroboration from operational sources and live vessel manifests.