FZUS51 KLWX 181828 CWFLWX Coastal Waters Forecast National Weather Service Baltimore MD/Washington DC 228 PM EDT Mon May 18 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. ANZ500-190800- 228 PM EDT Mon May 18 2026 .SYNOPSIS FOR THE TIDAL POTOMAC AND MD PORTION OF THE CHESAPEAKE BAY... High pressure will continue to strengthen offshore today through Tuesday leading to increased south to southwesterly flow. Expect Small Craft Advisories for channeling this afternoon and again Tuesday afternoon. Winds will subside during the late evening and overnight periods. Additional Small Craft Advisories will be needed Wednesday into Thursday as a cold front crosses the waters. The front will bring scattered to numerous showers and thunderstorms Wednesday afternoon and evening. Special Marine Warnings may be needed for stronger thunderstorms during this time. $$ ANZ535-190800- Tidal Potomac from Key Bridge to Indian Head- 228 PM EDT Mon May 18 2026 .THIS AFTERNOON...S winds 5 to 10 kt. Waves 1 ft. .TONIGHT...S winds 5 to 10 kt. Waves 1 ft. .TUE...SW winds 5 to 10 kt. Gusts up to 20 kt in the afternoon. Waves 1 ft. .TUE NIGHT...SW winds 5 to 10 kt with gusts to 20 kt. Waves 1 ft. .WED...SW winds 5 to 10 kt. Gusts up to 20 kt in the afternoon. Waves 1 ft. Showers likely. .WED NIGHT...N winds 5 to 10 kt. Waves 1 ft. Showers. .THU...NE winds 5 to 10 kt. Waves 1 ft. Showers likely through the day. A chance of showers through the night. .FRI...E winds 5 to 10 kt. Waves 1 ft. Showers. $$ ANZ536-190800- Tidal Potomac from Indian Head to Cobb Island- 228 PM EDT Mon May 18 2026 .THIS AFTERNOON...S winds 5 to 10 kt. Waves 1 ft. .TONIGHT...S winds 5 to 10 kt. Waves 1 ft. .TUE...SW winds 5 to 10 kt. Waves 1 ft. .TUE NIGHT...SW winds 10 to 15 kt with gusts to 20 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. .THU...NE winds 5 to 10 kt. Waves 1 ft. Showers likely through the day. A chance of showers through the night. .FRI...E winds 5 to 10 kt. Waves 1 ft. Showers likely. $$ ANZ537-190800- Tidal Potomac from Cobb Island to Smith Point- 228 PM EDT Mon May 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT TUESDAY... .THIS AFTERNOON...SE winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. .TONIGHT...S winds 10 to 15 kt...becoming SW late. Gusts up to 20 kt. Waves 1 to 2 ft. .TUE...S winds 5 to 10 kt. Waves 1 to 2 ft. .TUE NIGHT...S winds 10 to 15 kt. Waves 2 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. A chance of showers. .WED NIGHT...NW winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance of tstms. .THU...NE winds 10 to 15 kt...becoming E 5 to 10 kt. Waves 1 to 2 ft. Showers likely through the day. A chance of showers in the evening, then showers likely after midnight. .FRI...E winds 10 to 15 kt. Waves 2 ft. Showers likely. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ530-190800- Chesapeake Bay north of Pooles Island- 228 PM EDT Mon May 18 2026 .THIS AFTERNOON...S winds 5 to 10 kt. Waves 1 ft. .TONIGHT...SW winds 5 to 10 kt. Gusts up to 20 kt until early morning. Waves 1 ft. .TUE...SW winds 5 to 10 kt. Gusts up to 20 kt in the afternoon. Waves 1 ft. .TUE NIGHT...SW winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. Showers with a chance of tstms. .WED NIGHT...N winds 10 to 15 kt. Waves 1 ft. Showers. .THU...N winds 10 to 15 kt...becoming E around 5 kt. Waves 1 ft or less. A chance of showers. .FRI...E winds 5 to 10 kt. Waves 1 ft. A chance of showers in the morning, then showers likely. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ531-190800- Chesapeake Bay from Pooles Island to Sandy Point- 228 PM EDT Mon May 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT TUESDAY... .THIS AFTERNOON...S winds 10 kt with gusts to 20 kt. Waves 1 to 2 ft. .TONIGHT...S winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. .TUE...S winds 10 to 15 kt. Gusts up to 20 kt in the afternoon. Waves 1 to 2 ft. .TUE NIGHT...S winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. Showers. .WED NIGHT...N winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. Showers. .THU...NE winds 10 to 15 kt...becoming E around 5 kt. Waves 1 to 2 ft...subsiding to flat after midnight. Showers likely through the day. A chance of showers through the night. .FRI...E winds 5 to 10 kt. Waves 1 ft. Showers. $$ ANZ538-190800- Patapsco River including Baltimore Harbor- 228 PM EDT Mon May 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT TUESDAY... .THIS AFTERNOON...SE winds 10 kt. Waves 1 ft. .TONIGHT...S winds 5 to 10 kt. Gusts up to 20 kt in the evening. Waves 1 ft. .TUE...SW winds 5 to 10 kt. Waves 1 ft or less. .TUE NIGHT...SW winds 5 to 10 kt. Waves 1 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. Showers with a chance of tstms. .WED NIGHT...N winds 5 to 10 kt. Waves 1 ft. Showers. .THU...NE winds 5 to 10 kt. Waves 1 ft or less. Showers likely through the day. A chance of showers through the night. .FRI...E winds 5 to 10 kt. Waves 1 ft. Showers. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ539-190800- Chester River to Queenstown MD- 228 PM EDT Mon May 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT TUESDAY... .THIS AFTERNOON...S winds 5 to 10 kt. Waves 1 ft. .TONIGHT...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. .TUE...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. .TUE NIGHT...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. Showers likely. .WED NIGHT...NW winds 5 kt...becoming N 10 to 15 kt after midnight. Waves 1 ft. Showers. .THU...N winds 10 to 15 kt...becoming E around 5 kt. Waves 1 to 2 ft...subsiding to flat. Showers likely through the day. A chance of showers through the night. .FRI...E winds 5 to 10 kt. Waves 1 ft. Showers likely through the day, then showers through the night. $$ ANZ532-190800- Chesapeake Bay from Sandy Point to North Beach- 228 PM EDT Mon May 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT TUESDAY... .THIS AFTERNOON...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. .TONIGHT...S winds 10 to 15 kt with gusts to 20 kt. Waves 2 to 3 ft. .TUE...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. .TUE NIGHT...S winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. Showers likely. .WED NIGHT...N winds 10 to 15 kt. Gusts up to 20 kt after midnight. Waves 1 to 2 ft. Showers. .THU...N winds 10 to 15 kt...becoming E 5 to 10 kt. Waves 1 to 2 ft. Showers likely through the day, then a chance of showers through the night. .FRI...E winds 5 to 10 kt. Waves 1 ft. Showers. $$ ANZ540-190800- Eastern Bay- 228 PM EDT Mon May 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT TUESDAY... .THIS AFTERNOON...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft. .TONIGHT...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. .TUE...SW winds 10 to 15 kt. Gusts up to 20 kt in the afternoon. Waves 1 ft. .TUE NIGHT...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. Showers likely. .WED NIGHT...N winds 10 to 15 kt. Gusts up to 20 kt after midnight. Waves 1 ft. Showers. .THU...N winds 10 to 15 kt...becoming E 5 kt. Waves 1 ft or less. Showers likely through the day, then a chance of showers through the night. .FRI...E winds 5 to 10 kt. Waves 1 ft. Showers. $$ ANZ533-190800- Chesapeake Bay from North Beach to Drum Point- 228 PM EDT Mon May 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT TUESDAY... .THIS AFTERNOON...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. .TONIGHT...S winds 15 to 20 kt...diminishing to 10 kt after midnight. Waves 2 to 3 ft. .TUE...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. .TUE NIGHT...S winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. .WED...S winds 5 to 10 kt. Waves 1 to 2 ft. A chance of showers. .WED NIGHT...N winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. Showers likely. .THU...N winds 15 to 20 kt...becoming E 5 to 10 kt. Waves 2 to 3 ft...subsiding to 1 ft. Showers likely through the day, then a chance of showers through the night. .FRI...E winds 5 to 10 kt. Waves 1 to 2 ft. Showers. $$ ANZ541-190800- Choptank River to Cambridge MD and the Little Choptank River- 228 PM EDT Mon May 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT TUESDAY... .THIS AFTERNOON...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft. .TONIGHT...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. .TUE...S winds 10 to 15 kt. Gusts up to 20 kt in the afternoon. Waves 1 ft. .TUE NIGHT...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. .WED...SW winds 5 to 10 kt. Waves 1 ft. A chance of showers. .WED NIGHT...N winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft. Showers likely. .THU...N winds 10 to 15 kt...becoming E 5 kt. Waves 1 to 2 ft. Showers likely through the day, then a chance of showers through the night. .FRI...E winds 5 to 10 kt. Waves 1 ft. Showers. $$ ANZ542-190800- Patuxent River to Broomes Island MD- 228 PM EDT Mon May 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT TUESDAY... .THIS AFTERNOON...S winds 10 kt with gusts to 20 kt. Waves 1 ft. .TONIGHT...S winds 5 to 10 kt. Gusts up to 20 kt until early morning. Waves 1 ft. .TUE...SW winds 5 to 10 kt. Waves 1 ft. .TUE NIGHT...S 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. .THU...N winds 10 to 15 kt...becoming E around 5 kt. Waves 1 ft. Showers likely through the day, then a chance of showers through the night. .FRI...E winds 5 to 10 kt. Waves 1 ft. Showers likely. $$ ANZ534-190800- Chesapeake Bay from Drum Point to Smith Point- 228 PM EDT Mon May 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT TUESDAY... .THIS AFTERNOON...SE winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. .TONIGHT...S winds 10 to 15 kt with gusts to 20 kt. Waves 2 to 3 ft. .TUE...S winds 10 to 15 kt. Gusts up to 20 kt in the afternoon. Waves 2 to 3 ft. .TUE NIGHT...S winds 10 to 15 kt with gusts to 20 kt. Waves 2 to 3 ft. .WED...S winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. A chance of showers. .WED NIGHT...SE winds 10 to 15 kt...becoming N after midnight. Gusts up to 20 kt. Waves 2 ft. Showers likely. .THU...NE winds 10 to 15 kt...becoming E 5 to 10 kt. Waves 1 to 2 ft. Showers likely through the day, then a chance of showers through the night. .FRI...E winds 10 to 15 kt. Waves 2 ft. Showers likely. $$ ANZ543-190800- Tangier Sound and the inland waters surrounding Bloodsworth Island- 228 PM EDT Mon May 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM EDT TUESDAY... .THIS AFTERNOON...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. .TONIGHT...S winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. .TUE...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. .TUE NIGHT...S winds 10 to 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. A chance of showers. .WED NIGHT...SE winds 10 to 15 kt...becoming N 5 to 10 kt after midnight. Gusts up to 20 kt. Waves 1 to 2 ft. Showers likely. .THU...NE winds 10 to 15 kt...diminishing to 5 to 10 kt. Waves 1 ft. A chance of showers. .FRI...E winds 10 to 15 kt. Waves 1 ft. Showers likely. $$