Post-Tropical Cyclone Bertha: shipping impact

Per the latest NHC advisory, Post-Tropical Cyclone Bertha sits near 30.0N 96.0W with winds of 30 kt and central pressure 1008 mb, moving west at 14 kt. The system weakened over July 23, dropping from a 35 kt tropical storm through tropical depression to post-tropical status. ChartNav's monitor records a steep drop on the Houston Ship Channel & Galveston Bay, with a July 27 metric alert showing 9 transits against a 38-ship 17-day median, a 76% decline, after a July 26 12:50 alert logged 9 transits versus a 41-ship median. The Lower Mississippi River registered zero transits over the past 24 hours, matching its zero median, though a July 25 presence alert flagged 136 vessels, a 30% rise above the 105 median. The event remains active since July 19.