FZUS51 KLWX 181604 CWFLWX Coastal Waters Forecast National Weather Service Baltimore MD/Washington DC 1203 PM EDT Sat Jul 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- 1203 PM EDT Sat Jul 18 2026 .SYNOPSIS FOR THE TIDAL POTOMAC AND MD PORTION OF THE CHESAPEAKE BAY... A strong cold front will drop through the region tonight into Sunday. High pressure will build north of the area Monday before the next cold front approaches by midweek. Small Craft Advisories may be needed for portions of the waters Sunday, and again Monday night through Wednesday. Special Marine Warnings will likely be needed through this evening. $$ ANZ535-190800- Tidal Potomac from Key Bridge to Indian Head- 1203 PM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 11 PM EDT THIS EVENING... .THIS AFTERNOON...SW winds 10 kt with gusts to 20 kt. Waves 1 ft. Numerous showers and tstms. Patchy smoke. Vsby 1 NM or less. .TONIGHT...SW winds 5 to 10 kt. Gusts up to 20 kt early in the evening. Waves 1 ft. Numerous showers and tstms. .SUN...NW winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...NE winds around 5 kt. Waves 1 ft. .MON...E winds around 5 kt. Waves 1 ft. .MON NIGHT...SE winds around 5 kt. Waves 1 ft. A chance of showers. .TUE...S winds 5 to 10 kt. Waves 1 ft. Showers with tstms likely. .WED...W winds 5 to 10 kt. Waves 1 ft. Showers likely through the day. A chance of tstms through the night. A chance of showers in the evening. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ536-190800- Tidal Potomac from Indian Head to Cobb Island- 1203 PM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 11 PM EDT THIS EVENING... .THIS AFTERNOON...SW winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft. Scattered showers and tstms. Patchy smoke. Vsby 1 NM or less. .TONIGHT...SW winds 10 to 15 kt with gusts to 20 kt... becoming W 5 kt late. Waves 1 ft. Numerous showers with a chance of tstms. .SUN...NW winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...NE winds around 5 kt. Waves 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft. .MON NIGHT...SE winds 5 to 10 kt. Waves 1 ft. A chance of showers. .TUE...S winds 10 to 15 kt. Waves 1 ft. Showers with tstms likely. .WED...W winds 10 to 15 kt...becoming NW 5 to 10 kt. Waves 1 ft. Showers likely. A chance of tstms through the night, then a chance of showers after midnight. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ537-190800- Tidal Potomac from Cobb Island to Smith Point- 1203 PM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH LATE TONIGHT... .THIS AFTERNOON...SW winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. Scattered showers and tstms. .TONIGHT...SW winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. A chance of showers and tstms. .SUN...NW winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...NE winds 5 to 10 kt. Waves 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft. .MON NIGHT...SE winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance of tstms. .TUE...SW winds 15 to 20 kt. Waves 1 to 2 ft. Showers. Tstms likely through the night, then a chance of tstms after midnight. .WED...SW winds 15 to 20 kt...becoming NW 5 to 10 kt. Waves 1 to 2 ft. Showers likely through the day. A chance of tstms through the night. A chance of showers through the night. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ530-190800- Chesapeake Bay north of Pooles Island- 1203 PM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 11 PM EDT THIS EVENING... .THIS AFTERNOON...SW winds 15 kt with gusts to 20 kt. Waves 2 ft. Numerous showers and tstms. Areas of smoke. Vsby 1 NM or less. .TONIGHT...SW winds 10 to 15 kt...becoming W 5 to 10 kt late. Gusts up to 20 kt. Waves 1 to 2 ft. Numerous showers and tstms. .SUN...NW winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...N winds 5 to 10 kt. Waves 1 ft. .MON...E winds around 5 kt. Waves 1 ft. .MON NIGHT...SE winds 5 to 10 kt. Waves 1 ft. A chance of showers. .TUE...S winds 10 to 15 kt...becoming SW 15 to 20 kt after midnight. Waves 1 to 2 ft. Showers likely in the morning, then showers with a chance of tstms. .WED...W winds 10 to 15 kt...becoming NW 5 to 10 kt. Waves 1 ft. Showers likely through the day. A chance of tstms through the night. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ531-190800- Chesapeake Bay from Pooles Island to Sandy Point- 1203 PM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 11 PM EDT THIS EVENING... .THIS AFTERNOON...S winds 15 kt with gusts to 20 kt. Waves 2 ft. Numerous showers and tstms. Areas of smoke. Vsby 1 NM or less. .TONIGHT...SW winds 10 to 15 kt...becoming W late. Gusts up to 20 kt. Waves 1 to 2 ft. Numerous showers and tstms. .SUN...NW winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...NE winds 5 to 10 kt. Waves 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft. .MON NIGHT...SE winds 5 to 10 kt. Waves 1 ft. A chance of showers. .TUE...S winds 15 to 20 kt...becoming SW after midnight. Waves 1 to 2 ft. Showers with tstms likely. .WED...W winds 10 to 15 kt...becoming NW. Waves 1 to 2 ft. Showers likely in the morning, then a chance of showers and tstms through the night. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ538-190800- Patapsco River including Baltimore Harbor- 1203 PM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 11 PM EDT THIS EVENING... .THIS AFTERNOON...SW winds 10 kt with gusts to 20 kt. Waves 1 ft. Numerous showers and tstms. Areas of smoke. Vsby 1 NM or less. .TONIGHT...SW winds 5 to 10 kt with gusts to 20 kt. Waves 1 ft. Numerous showers and tstms. .SUN...NW winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...N winds 5 kt. Waves less than 1 ft. .MON...E winds 5 kt. Waves less than 1 ft. .MON NIGHT...SE winds 5 to 10 kt. Waves 1 ft. A chance of showers. .TUE...S winds 10 to 15 kt...becoming SW after midnight. Waves 1 ft. Showers with tstms likely. .WED...W winds 5 to 10 kt. Waves 1 ft. Showers likely in the morning, then a chance of showers and tstms through the night. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ539-190800- Chester River to Queenstown MD- 1203 PM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 11 PM EDT THIS EVENING... .THIS AFTERNOON...S winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. Numerous showers and tstms. Patchy smoke. Vsby 1 NM or less. .TONIGHT...SW winds 5 to 10 kt with gusts to 20 kt. Waves 1 to 2 ft. Numerous showers and tstms. .SUN...NW winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...NE winds 5 kt. Waves less than 1 ft. .MON...NE winds around 5 kt. Waves 1 ft or less. .MON NIGHT...SE winds 5 to 10 kt. Waves 1 ft. A chance of showers. .TUE...S winds 10 to 15 kt...becoming SW after midnight. Waves 1 to 2 ft. Showers likely in the morning, then showers with a chance of tstms. .WED...SW winds 10 to 15 kt...becoming NW 5 to 10 kt. Waves 1 to 2 ft. Showers likely. A chance of tstms through the night, then a chance of showers after midnight. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ532-190800- Chesapeake Bay from Sandy Point to North Beach- 1203 PM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 11 PM EDT THIS EVENING... .THIS AFTERNOON...S winds 15 kt with gusts to 20 kt. Waves 2 ft. Numerous showersand tstms. Patchy smoke. Vsby 1 NM or less. .TONIGHT...SW winds 10 to 15 kt...becoming W late. Gusts up to 20 kt. Waves 1 to 2 ft. Numerous showers and tstms. .SUN...N winds 10 kt. Waves 1 ft. .SUN NIGHT...NE winds 5 to 10 kt. Waves 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft. .MON NIGHT...SE winds 5 to 10 kt. Waves 2 ft. A chance of showers. .TUE...S winds 15 to 20 kt. Waves 2 to 3 ft. Showers. Tstms likely through the night, then a chance of tstms after midnight. .WED...W winds 10 to 15 kt...becoming NW after midnight. Waves 1 to 2 ft. Showers likely. A chance of tstms through the night, then a chance of showers after midnight. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ540-190800- Eastern Bay- 1203 PM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 11 PM EDT THIS EVENING... .THIS AFTERNOON...S winds 15 kt with gusts to 20 kt. Waves 1 to 2 ft. Numerous showers and tstms. Patchy smoke. Vsby 1 NM or less. .TONIGHT...SW winds 10 to 15 kt...becoming W late. Gusts up to 20 kt. Waves 1 to 2 ft. Numerous showers and tstms. .SUN...NW winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...NE winds 5 to 10 kt. Waves 1 ft. .MON...NE winds around 5 kt. Waves 1 ft or less. .MON NIGHT...SE winds 5 to 10 kt. Waves 1 ft. A chance of showers. .TUE...S winds 15 to 20 kt. Waves 1 to 2 ft. Showers likely in the morning, then showers with a chance of tstms. .WED...W winds 10 to 15 kt...becoming NW after midnight. Waves 1 to 2 ft. Showers likely. A chance of tstms through the night, then a chance of showers after midnight. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ533-190800- Chesapeake Bay from North Beach to Drum Point- 1203 PM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 11 PM EDT THIS EVENING... .THIS AFTERNOON...S winds 15 kt with gusts to 20 kt. Waves 2 ft. Numerous showers and tstms. Patchy smoke. Vsby 1 NM or less. .TONIGHT...SW winds 10 to 15 kt...becoming W late. Gusts up to 20 kt. Waves 1 to 2 ft. Numerous showers and tstms. .SUN...N winds 10 kt. Waves 1 ft. .SUN NIGHT...NE winds 5 to 10 kt. Waves 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft. .MON NIGHT...SE winds 10 to 15 kt. Waves 2 ft. A chance of showers and tstms. .TUE...S winds 15 to 20 kt. Waves 1 to 2 ft...building to 2 to 3 ft. Showers. Tstms likely in the afternoon, then a chance of tstms through the night. .WED...SW winds 15 to 20 kt...becoming NW 10 to 15 kt. Waves 2 ft. Showers likely. A chance of tstms through the night, then a chance of showers after midnight. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ541-190800- Choptank River to Cambridge MD and the Little Choptank River- 1203 PM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 11 PM EDT THIS EVENING... .THIS AFTERNOON...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. Numerous showers and tstms. Patchy smoke. Vsby 1 NM or less. .TONIGHT...SW winds 10 to 15 kt...becoming W late. Gusts up to 20 kt. Waves 1 to 2 ft. Numerous showers and tstms. .SUN...NW winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...NE winds 5 to 10 kt. Waves 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft. .MON NIGHT...SE winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms. .TUE...S winds 15 to 20 kt. Waves 1 to 2 ft. Showers likely in the morning, then showers with a chance of tstms. .WED...SW winds 15 to 20 kt...becoming NW 10 to 15 kt. Waves 1 to 2 ft. Showers likely. A chance of tstms through the night, then a chance of showers after midnight. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ542-190800- Patuxent River to Broomes Island MD- 1203 PM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 11 PM EDT THIS EVENING... .THIS AFTERNOON...SW winds 10to 15 kt with gusts to 20 kt. Waves 1 ft. Numerous showers and tstms. Patchy smoke. Vsby 1 NM or less. .TONIGHT...SW winds 10 to 15 kt with gusts to 20 kt... becoming W 5 kt late. Waves 1 ft. Numerous showers and tstms. .SUN...NW winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...NE winds 5 to 10 kt. Waves 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft. .MON NIGHT...SE winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance of tstms. .TUE...S winds 10 to 15 kt. Waves 1 ft. Showers. Tstms likely through the night, then a chance of tstms after midnight. .WED...SW winds 10 to 15 kt...becoming NW 5 to 10 kt. Waves 1 ft. Showers likely. A chance of tstms through the night, then a chance of showers after midnight. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ534-190800- Chesapeake Bay from Drum Point to Smith Point- 1203 PM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH LATE TONIGHT... .THIS AFTERNOON...S winds 15 kt with gusts to 20 kt. Waves 2 to 3 ft. Scattered showers and tstms. .TONIGHT...SW winds 10 to 15 kt with gusts to 20 kt. Waves 2 to 3 ft. A chance of showers and tstms. .SUN...NW winds 5 to 10 kt. Waves 1 to 2 ft. .SUN NIGHT...NE winds 5 to 10 kt. Waves 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft. .MON NIGHT...SE winds 10 to 15 kt. Waves 2 ft. Showers likely with a chance of tstms. .TUE...S winds 20 to 25 kt. Waves 2 to 3 ft. Showers likely in the morning, then showers with a chance of tstms. .WED...SW winds 20 to 25 kt...becoming W 10 to 15 kt in the evening, then becoming NW after midnight. Waves 2 to 3 ft. Showers. A chance of tstms through the night, then a chance of showers after midnight. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ543-190800- Tangier Sound and the inland waters surrounding Bloodsworth Island- 1203 PM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH LATE TONIGHT... .THIS AFTERNOON...S winds 15 kt with gusts to 25 kt. Waves 2 ft. Scattered showers and tstms. .TONIGHT...SW winds 15 kt...becoming W late. Gusts up to 25 kt. Waves 2 ft. A chance of showers and tstms. .SUN...NW winds 10 to 15 kt...diminishing to 5 to 10 kt late. Waves 1 ft. .SUN NIGHT...NE winds 5 to 10 kt. Waves 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft. .MON NIGHT...SE winds 10 kt. Waves 1 ft. Showers likely with a chance of tstms. .TUE...S winds 20 to 25 kt. Waves 1 to 2 ft...building to 3 ft. Showers likely in the morning, then showers with a chance of tstms. .WED...SW winds 20 to 25 kt...becoming W 10 to 15 kt in the evening, then becoming NW after midnight. Waves 2 to 3 ft. Showers. A chance of tstms through the night, then a chance of showers after midnight. Winds and waves higher and visibilities lower in and near tstms. $$