NWS Marine Forecast



 Hazardous marine condition(s):
 Small Craft Advisory
 Hazardous Weather Outlook
   ANZ500-202000-  1057 AM EDT Thu Aug 20 2026      .SYNOPSIS FOR THE TIDAL POTOMAC AND MD PORTION OF THE CHESAPEAKE BAY...    A cold front will slowly approach from Pennsylvania today as a warm  front approaches from the Virginia Tidewater and Delmarva Peninsula.  Multiple weak waves of low pressure along these boundaries will  ignite scattered to numerous showers and thunderstorms. Some storms  may be severe particularly east of the Blue Ridge and Catoctin  Mountains, and especially across the Interstate 95 corridor toward  the Chesapeake Bay. This frontal system is expected to stall near or  just southeast of the Mid-Atlantic, and additional ripples of low  pressure riding along it may result in periodic showers and a few  thunderstorms at times through the upcoming weekend.    $$
   ANZ536-202000-  Tidal Potomac from Indian Head to Cobb Island-  1057 AM EDT Thu Aug 20 2026    SMALL CRAFT ADVISORY IN EFFECT FROM 2 PM THIS AFTERNOON TO 8 PM  EDT THIS EVENING    REST OF TODAY  S winds 5 to 10 kt. Gusts up to 20 kt this  afternoon. Waves 1 ft. Isolated showers and tstms late this morning,  then numerous showers and scattered tstms this afternoon.  TONIGHT  N winds 5 to 10 kt. Gusts up to 20 kt early in the  evening. Waves 1 ft. Numerous showers and scattered tstms. Patchy  fog. Vsby 1 NM or less.  FRI  NE winds around 5 kt. Waves 1 ft. A chance of showers.  FRI NIGHT  E winds around 5 kt. Waves 1 ft. Showers with a chance  of tstms.  SAT  S winds around 5 kt. Waves 1 ft. Showers likely.  SAT NIGHT  SW winds around 5 kt. Waves 1 ft or less. A chance of  showers.  SUN  NW winds around 5 kt. Waves 1 ft. A chance of showers through  the night.  MON  NW winds around 5 kt. Waves 1 ft.    Winds and waves higher and visibilities lower in and near tstms.    $$