Tropical Storm Bertha — Track, Cone & Fleet

48-hour time-lapse

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Forecast controls — cone · models · time

Storm & forecast

Daily transits vs baseline

Vessels in the zone

NHC Forecast Statements

Public Advisory

Forecast Discussion — the forecaster's reasoning

This storm has an active shipping-impact event with metric alerts and a curated briefing: Tropical Storm Bertha on the News desk.

Data & citation

Transit counts are gate-line crossings computed hourly from ChartNav's own live AIS network (terrestrial receivers; coverage varies by zone — the coverage figure above says how complete the picture is, and reporting gaps are only flagged for vessels that were underway and stopped reporting globally). Baselines are rolling medians of complete days. Numbers may differ from weekly satellite-AIS datasets such as IMF PortWatch, which lag by several days but see areas terrestrial receivers cannot.