FZUS51 KLWX 200627 CWFLWX Coastal Waters Forecast National Weather Service Baltimore MD/Washington DC 226 AM EDT Wed May 20 2026 Tidal Potomac River and Maryland portion of Chesapeake Bay. Forecasts of wave heights do not include effects of wind direction relative to tidal currents. Expect higher waves when winds are blowing against the tidal flow. Waves flat where waters are iced over. ANZ500-202000- 226 AM EDT Wed May 20 2026 .SYNOPSIS FOR THE TIDAL POTOMAC AND MD PORTION OF THE CHESAPEAKE BAY... Small Craft Advisories may be needed through Thursday as a cold front slowly crosses the waters. The front will bring scattered to numerous showers and thunderstorms this afternoon and evening. Special Marine Warnings may be needed for stronger thunderstorms during this time. Additional Small Craft Advisories will be needed Thursday afternoon and evening in northerly channeling. Increased onshore flow will keep Small Craft Advisory conditions going across the waters at times Friday into the weekend. $$ ANZ535-202000- Tidal Potomac from Key Bridge to Indian Head- 226 AM EDT Wed May 20 2026 .OVERNIGHT...SW winds 5 to 10 kt. Waves 1 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance of tstms. .WED NIGHT...N winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance of tstms. .THU...NE winds 5 to 10 kt. Waves 1 ft. Showers likely. .THU NIGHT...NE winds 5 to 10 kt. Waves 1 ft. Showers likely. .FRI...NE winds 5 to 10 kt. Waves 1 ft. Showers. .FRI NIGHT...E winds 5 to 10 kt. Waves 1 ft. Showers. .SAT...E winds 5 to 10 kt. Waves 1 ft. Showers. .SUN...E winds around 5 kt. Waves 1 ft. A chance of showers. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ536-202000- Tidal Potomac from Indian Head to Cobb Island- 226 AM EDT Wed May 20 2026 .OVERNIGHT...SW winds 10 kt. Waves 1 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. A chance of showers. .WED NIGHT...N winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms. .THU...NE winds 5 to 10 kt. Waves 1 ft. Showers likely. .THU NIGHT...NE winds 5 to 10 kt. Waves 1 ft. Showers likely. .FRI...NE winds 5 to 10 kt. Waves 1 ft. Showers. .FRI NIGHT...NE winds 5 to 10 kt. Waves 1 ft. Showers likely. .SAT...NE winds around 5 kt. Waves 1 ft. Showers. .SUN...E winds around 5 kt. Waves 1 ft. A chance of showers. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ537-202000- Tidal Potomac from Cobb Island to Smith Point- 226 AM EDT Wed May 20 2026 ...SMALL CRAFT ADVISORY IN EFFECT FROM THIS AFTERNOON THROUGH THIS EVENING... .OVERNIGHT...SW winds 10 kt. Waves 1 ft. .WED...S winds 5 to 10 kt. Waves 1 ft. .WED NIGHT...N winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms. .THU...NE winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. A chance of showers. .THU NIGHT...NE winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. Showers. .FRI...E winds 10 to 15 kt with gusts to 20 kt. Waves 2 to 3 ft. Showers. .FRI NIGHT...NE winds 10 to 15 kt with gusts to 20 kt. Waves 2 to 3 ft. Showers likely. .SAT...E winds 5 to 10 kt. Waves 1 to 2 ft. Showers likely. A chance of tstms through the night. .SUN...E winds 5 kt. Waves less than 1 ft. A chance of showers. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ530-202000- Chesapeake Bay north of Pooles Island- 226 AM EDT Wed May 20 2026 .OVERNIGHT...SW winds 5 kt. Waves less than 1 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance of tstms. .WED NIGHT...N winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance of tstms. .THU...NE winds 5 to 10 kt. Waves 1 ft. Showers. .THU NIGHT...NE winds around 5 kt. Waves 1 ft. A chance of showers. .FRI...E winds 5 to 10 kt with gusts to 20 kt. Waves 1 ft. Showers. .FRI NIGHT...E winds 10 to 15 kt. Waves 1 ft. Showers. .SAT...E winds 10 to 15 kt. Waves 1 ft. Showers. .SUN...E winds 5 to 10 kt. Waves 1 ft. Showers likely, mainly in the morning. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ531-202000- Chesapeake Bay from Pooles Island to Sandy Point- 226 AM EDT Wed May 20 2026 .OVERNIGHT...SW winds 10 kt. Waves 1 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance of tstms. .WED NIGHT...N winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance of tstms. .THU...NE winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. Showers. .THU NIGHT...NE winds 5 to 10 kt. Waves 1 ft. A chance of showers. .FRI...E winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. Showers. .FRI NIGHT...E winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. Showers. .SAT...E winds 10 to 15 kt. Waves 1 to 2 ft. Showers. .SUN...NE winds 5 to 10 kt. Waves 1 ft. A chance of showers. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ538-202000- Patapsco River including Baltimore Harbor- 226 AM EDT Wed May 20 2026 .OVERNIGHT...SW winds 5 kt. Waves flat. .WED...SW winds 5 to 10 kt. Waves 1 ft or less. Showers likely with a chance of tstms. .WED NIGHT...N winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance of tstms. .THU...NE winds 10 kt. Waves 1 ft. Showers. .THU NIGHT...NE winds 5 kt. Waves less than 1 ft. A chance of showers. .FRI...E winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. Showers. .FRI NIGHT...E winds 10 kt with gusts to 20 kt. Waves 1 ft. Showers. .SAT...E winds 5 to 10 kt. Waves 1 ft. Showers. .SUN...E winds 5 kt. Waves less than 1 ft. A chance of showers. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ539-202000- Chester River to Queenstown MD- 226 AM EDT Wed May 20 2026 .OVERNIGHT...SW winds 10 kt. Waves 1 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance of tstms. .WED NIGHT...N winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance of tstms. .THU...NE winds 10 kt with gusts to 20 kt. Waves 1 ft. Showers likely. .THU NIGHT...NE winds 5 to 10 kt. Waves 1 ft. Showers likely. .FRI...E winds 10 kt with gusts to 20 kt. Waves 1 ft. Showers. .FRI NIGHT...E winds 10 kt. Waves 1 ft. Showers. .SAT...E winds 5 to 10 kt. Waves 1 ft. Showers. .SUN...E winds 5 to 10 kt. Waves 1 ft or less. A chance of showers. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ532-202000- Chesapeake Bay from Sandy Point to North Beach- 226 AM EDT Wed May 20 2026 .OVERNIGHT...SW winds 10 kt. Waves 1 ft. .WED...S winds 5 to 10 kt. Waves 1 to 2 ft. A chance of showers and tstms. .WED NIGHT...N winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance of tstms. .THU...NE winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. Showers likely. .THU NIGHT...NE winds 5 to 10 kt. Waves 1 to 2 ft. Showers likely. .FRI...E winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. Showers. .FRI NIGHT...E winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. Showers. .SAT...E winds 10 to 15 kt. Waves 1 to 2 ft. Showers. .SUN...NE winds 5 to 10 kt. Waves 1 ft. A chance of showers. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ540-202000- Eastern Bay- 226 AM EDT Wed May 20 2026 .OVERNIGHT...SW winds 10 kt. Waves 1 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. A chance of showers. .WED NIGHT...N winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance of tstms. .THU...NE winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft. Showers likely. .THU NIGHT...NE winds 5 to 10 kt. Waves 1 ft. Showers likely. .FRI...E winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft. Showers. .FRI NIGHT...E winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft. Showers. .SAT...E winds 5 to 10 kt. Waves 1 ft. Showers. .SUN...E winds 5 kt. Waves less than 1 ft. A chance of showers. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ533-202000- Chesapeake Bay from North Beach to Drum Point- 226 AM EDT Wed May 20 2026 ...SMALL CRAFT ADVISORY IN EFFECT FROM THIS AFTERNOON THROUGH THIS EVENING... .OVERNIGHT...SW winds 10 kt. Waves 1 ft. .WED...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. .WED NIGHT...N winds 10 to 15 kt. Waves 1 to 2 ft. A chance of showers and tstms. .THU...NE winds 10 to 15 kt with gusts to 20 kt. Waves 2 to 3 ft. Showers likely. .THU NIGHT...NE winds 10 kt with gusts to 20 kt. Waves 2 ft. Showers likely. .FRI...E winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. Showers. .FRI NIGHT...E winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. Showers. .SAT...E winds 5 to 10 kt. Waves 1 to 2 ft. Showers through the day, then showers likely through the night. .SUN...E winds 5 kt. Waves less than 1 ft. A chance of showers. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ541-202000- Choptank River to Cambridge MD and the Little Choptank River- 226 AM EDT Wed May 20 2026 .OVERNIGHT...SW winds 10 kt. Waves 1 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. .WED NIGHT...N winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms. .THU...NE winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. Showers likely. .THU NIGHT...NE winds 5 to 10 kt with gusts to 20 kt. Waves 1 ft. Showers likely. .FRI...E winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. Showers. .FRI NIGHT...E winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. Showers. .SAT...E winds 5 to 10 kt. Waves 1 ft. Showers through the day, then showers likely through the night. .SUN...E winds 5 kt. Waves less than 1 ft. A chance of showers. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ542-202000- Patuxent River to Broomes Island MD- 226 AM EDT Wed May 20 2026 ...SMALL CRAFT ADVISORY IN EFFECT FROM THIS AFTERNOON THROUGH THIS EVENING... .OVERNIGHT...SW winds 10 kt. Waves 1 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. .WED NIGHT...N winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms. .THU...N winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft. A chance of showers. .THU NIGHT...NE winds 5 to 10 kt. Waves 1 ft. Showers likely. .FRI...NE winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft. Showers. .FRI NIGHT...NE winds 5 to 10 kt. Waves 1 ft. Showers. .SAT...NE winds 5 to 10 kt. Waves 1 ft. Showers through the day, then showers likely with a chance of tstms through the night. .SUN...E winds around 5 kt. Waves 1 ft. A chance of showers. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ534-202000- Chesapeake Bay from Drum Point to Smith Point- 226 AM EDT Wed May 20 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 3 AM EDT EARLY THIS MORNING... ...SMALL CRAFT ADVISORY IN EFFECT FROM THIS AFTERNOON THROUGH THIS EVENING... .OVERNIGHT...SW winds 15 kt with gusts to 20 kt. Waves 2 ft. .WED...SW winds 10 to 15 kt with gusts to 20 kt... becoming S with gusts to 20 kt in the afternoon. Waves 2 ft. .WED NIGHT...SE winds 10 to 15 kt with gusts to 20 kt...becoming NE with gusts to 20 kt late in the evening, then becoming N 5 to 10 kt after midnight. Waves 3 ft...subsiding to 1 ft after midnight. A chance of showers and tstms. .THU...NE winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. A chance of showers. .THU NIGHT...NE winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. A chance of showers. .FRI...NE winds 15 kt with gusts to 20 kt. Waves 3 ft. Showers. .FRI NIGHT...E winds 10 to 15 kt with gusts to 20 kt. Waves 2 to 3 ft. Showers. .SAT...E winds 10 to 15 kt. Waves 1 to 2 ft. Showers through the day, then showers likely with a chance of tstms through the night. .SUN...E winds 5 to 10 kt. Waves 1 ft. A chance of showers. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ543-202000- Tangier Sound and the inland waters surrounding Bloodsworth Island- 226 AM EDT Wed May 20 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 3 AM EDT EARLY THIS MORNING... ...SMALL CRAFT ADVISORY IN EFFECT FROM THIS AFTERNOON THROUGH THIS EVENING... .OVERNIGHT...SW winds 15 kt with gusts to 20 kt. Waves 2 ft. .WED...S winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. .WED NIGHT...S winds 10 to 15 kt with gusts to 20 kt...becoming E with gusts to 20 kt late in the evening, then becoming N 5 kt after midnight. Waves 1 to 2 ft. A chance of showers. .THU...NE winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft. A chance of showers. .THU NIGHT...NE winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft. Showers likely. .FRI...NE winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. Showers. .FRI NIGHT...E winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. Showers. .SAT...E winds 10 to 15 kt. Waves 1 ft. Showers through the day, then showers likely with a chance of tstms through the night. .SUN...E winds 5 to 10 kt. Waves 1 ft. A chance of showers. Winds and waves higher and visibilities lower in and near tstms. $$