FZUS51 KLWX 181345 CWFLWX Coastal Waters Forecast National Weather Service Baltimore MD/Washington DC 945 AM 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. ANZ500-182000- 945 AM EDT Sat Jul 18 2026 .SYNOPSIS FOR THE TIDAL POTOMAC AND MD PORTION OF THE CHESAPEAKE BAY... A warm front will lift north of the area this morning. 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 this afternoon and evening. $$ ANZ535-182000- Tidal Potomac from Key Bridge to Indian Head- 945 AM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING... .REST OF TODAY...SW winds 10 kt with gusts to 20 kt. Waves 1 ft. Areas of smoke late this morning, then patchy smoke this afternoon. Numerous showers and tstms this afternoon with vsby 1 NM or less. .TONIGHT...SW winds 5 to 10 kt. Gusts up to 20 kt in the evening. Waves 1 ft. Numerous showers and tstms. .SUN...NW winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...NE winds around 5 kt. Waves 1 ft. .MON...E winds around 5 kt. Waves 1 ft. A chance of showers. .MON NIGHT...SE winds around 5 kt. Waves 1 ft. A chance of showers and tstms. .TUE...SW winds 5 to 10 kt. Waves 1 ft. A chance of showers in the morning, then showers with a chance of tstms. .WED...W winds 5 to 10 kt. Waves 1 ft. A chance of showers. A chance of tstms through the night. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ536-182000- Tidal Potomac from Indian Head to Cobb Island- 945 AM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING... .REST OF TODAY...S winds 5 to 10 kt...becoming SW 15 kt late. Gusts up to 20 kt. Waves 1 ft. Areas of smoke late this morning, then patchy smoke this afternoon. Scattered showers and tstms this afternoon. Vsby 1 to 3 NM...decreasing to 1 NM or less this afternoon. .TONIGHT...SW winds 10 to 15 kt with gusts to 20 kt... becoming W 5 kt after midnight. Waves 1 ft. Numerous showers and scattered tstms. .SUN...NW winds 5 kt. Waves less than 1 ft. .SUN NIGHT...NE winds around 5 kt. Waves 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft. A chance of showers. .MON NIGHT...SE winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms. .TUE...SW winds 10 to 15 kt. Waves 1 ft. A chance of showers in the morning, then showers likely with a chance of tstms. .WED...W winds 5 to 10 kt. Waves 1 ft. A chance of showers. A chance of tstms through the night. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ537-182000- Tidal Potomac from Cobb Island to Smith Point- 945 AM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH LATE TONIGHT... .REST OF TODAY...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. Areas of smoke with patchy fog late this morning. Scattered showers and tstms this afternoon. Vsby 1 to 3 NM late this morning. .TONIGHT...SW winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. A chance of showers and tstms. .SUN...NW winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...NE winds 5 kt. Waves less than 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft. A chance of showers. .MON NIGHT...SE winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms. .TUE...SW winds 10 to 15 kt. Waves 1 to 2 ft. A chance of tstms. Showers likely. .WED...SW winds 10 to 15 kt...becoming NW 5 to 10 kt. Waves 1 to 2 ft. A chance of showers in the morning, then showers likely with a chance of tstms through the night. A chance of showers after midnight. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ530-182000- Chesapeake Bay north of Pooles Island- 945 AM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING... .REST OF TODAY...SW winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. Isolated showers and tstms late this morning, then numerous showers and tstms this afternoon. Smoke with patchy fog late this morning, then areas of smoke this afternoon with vsby 1 NM or less. .TONIGHT...W winds 10 to 15 kt...diminishing to 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 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 10 to 15 kt...becoming SW after midnight. Waves 1 to 2 ft. A chance of tstms. A chance of showers in the morning, then showers. .WED...W winds 10 to 15 kt...becoming NW 5 to 10 kt. Waves 1 ft. A chance of showers. A chance of tstms through the night. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ531-182000- Chesapeake Bay from Pooles Island to Sandy Point- 945 AM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING... .REST OF TODAY...S winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. Isolated showers and tstms late this morning, then numerous showers and tstms this afternoon. Smoke with patchy fog late this morning, then areas of smoke this afternoon. Vsby 1 to 3 NM... decreasing to 1 NM or less this afternoon. .TONIGHT...SW winds 10 to 15 kt...becoming W after midnight. Gusts up to 20 kt. Waves 1 to 2 ft. Numerous showers and tstms. .SUN...N winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...NE winds 5 to 10 kt. Waves 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft. .MON NIGHT...SE winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms. .TUE...S winds 10 to 15 kt...becoming SW after midnight. Waves 1 to 2 ft. A chance of tstms. A chance of showers in the morning, then showers. .WED...W winds 10 to 15 kt...becoming NW. Waves 1 to 2 ft. A chance of showers. A chance of tstms through the night. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ538-182000- Patapsco River including Baltimore Harbor- 945 AM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING... .REST OF TODAY...S winds 10 kt...becoming SW late. Gusts up to 20 kt. Waves 1 ft. Smoke late this morning, then areas of smoke this afternoon. Numerous showers and tstms this afternoon. Vsby 1 to 3 NM...decreasing to 1 NM or less this afternoon. .TONIGHT...W winds 5 to 10 kt with gusts to 20 kt. Waves 1 ft. Numerous showers and tstms. .SUN...N winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...NE winds 5 kt. Waves less than 1 ft. .MON...E winds 5 kt. Waves less than 1 ft. .MON NIGHT...S winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms. .TUE...S winds 5 to 10 kt. Waves 1 ft. A chance of tstms. A chance of showers in the morning, then showers. .WED...W winds 5 to 10 kt. Waves 1 ft. A chance of showers. A chance of tstms through the night. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ539-182000- Chester River to Queenstown MD- 945 AM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING... .REST OF TODAY...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. Smoke with patchy fog late this morning, then patchy smoke this afternoon. Numerous showers and tstms this afternoon. Vsby 1 to 3 NM...decreasing to 1 NM or less this afternoon. .TONIGHT...W winds 5 to 10 kt with gusts to 20 kt. Waves 1 to 2 ft. Numerous showers and tstms. .SUN...N winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...NE winds 5 to 10 kt. Waves 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft or less. .MON NIGHT...S winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms. .TUE...S winds 10 to 15 kt. Waves 1 to 2 ft. A chance of tstms. A chance of showers in the morning, then showers. .WED...W winds 10 to 15 kt...becoming NW 5 to 10 kt. Waves 1 to 2 ft. Showers likely in the morning, then a chance of showers and tstms through the night. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ532-182000- Chesapeake Bay from Sandy Point to North Beach- 945 AM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING... .REST OF TODAY...S winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft. Smoke with patchy fog late this morning, then patchy smoke this afternoon. Numerous showers and tstms this afternoon. Vsby 1 to 3 NM...decreasing to 1 NM or less this afternoon. .TONIGHT...SW winds 10 to 15 kt...becoming W after midnight. 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...S winds 5 to 10 kt. Waves 2 ft. A chance of showers and tstms. .TUE...S winds 10 to 15 kt. Waves 2 to 3 ft. A chance of tstms. A chance of showers in the morning, then showers. .WED...W winds 10 to 15 kt...becoming NW. Waves 1 to 2 ft. A chance of showers. A chance of tstms through the night. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ540-182000- Eastern Bay- 945 AM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING... .REST OF TODAY...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. Smoke with patchy fog late this morning, then patchy smoke this afternoon. Numerous showers and tstms this afternoon. Vsby 1 to 3 NM...decreasing to 1 NM or less this afternoon. .TONIGHT...SW winds 10 to 15 kt...becoming W 5 to 10 kt after midnight. Gusts up to 20 kt. Waves 1 to 2 ft. Numerous showers and tstms. .SUN...N winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...NE winds 5 to 10 kt. Waves 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft or less. .MON NIGHT...S winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms. .TUE...S winds 10 to 15 kt. Waves 1 to 2 ft. A chance of tstms. A chance of showers in the morning, then showers. .WED...W winds 10 to 15 kt...becoming NW. Waves 1 to 2 ft. Showers likely in the morning, then a chance of showers and tstms through the night. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ533-182000- Chesapeake Bay from North Beach to Drum Point- 945 AM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING... .REST OF TODAY...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. Areas of smoke with patchy fog late this morning, then patchy smoke this afternoon. Numerous showers and tstms this afternoon. Vsby 1 to 3 NM...decreasing to 1 NM or less this afternoon. .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...S winds 10 to 15 kt. Waves 2 ft. A chance of showers and tstms. .TUE...S winds 5 to 10 kt...becoming SW 15 to 20 kt. Waves 1 to 2 ft...building to 2 to 3 ft. A chance of tstms. .WED...W winds 10 to 15 kt...becoming NW. Waves 2 ft. A chance of showers. A chance of tstms through the night. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ541-182000- Choptank River to Cambridge MD and the Little Choptank River- 945 AM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING... .REST OF TODAY...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 to 2 ft. Areas of smoke with patchy fog late this morning, then patchy smoke this afternoon. Numerous showers and tstms this afternoon. Vsby 1 to 3 NM...decreasing to 1 NM or less this afternoon. .TONIGHT...SW winds 10 to 15 kt...becoming W late. Gusts up to 20 kt. Waves 1 to 2 ft. Numerous showers and tstms. .SUN...NW winds 5 to 10 kt. Waves 1 ft. .SUN NIGHT...NE winds 5 to 10 kt. Waves 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft. .MON NIGHT...S winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms. .TUE...S winds 15 to 20 kt. Waves 1 to 2 ft. A chance of tstms. A chance of showers in the morning, then showers. .WED...W winds 10 to 15 kt...becoming NW. Waves 1 to 2 ft. Showers likely in the morning, then a chance of showers and tstms through the night. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ542-182000- Patuxent River to Broomes Island MD- 945 AM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH THIS EVENING... .REST OF TODAY...S winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft. Areas of smoke with patchy fog late this morning, then patchy smoke this afternoon. Numerous showers and tstms this afternoon. Vsby 1 to 3 NM...decreasing to 1 NM or less this afternoon. .TONIGHT...SW winds 10 to 15 kt...becoming W 5 kt after midnight. Gusts up to 20 kt. Waves 1 ft. Numerous showers and tstms. .SUN...N 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. A chance of showers. .MON NIGHT...SE winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms. .TUE...SW winds 10 to 15 kt. Waves 1 ft. A chance of tstms. A chance of showers in the morning, then showers likely. .WED...W winds 5 to 10 kt. Waves 1 ft. A chance of showers in the morning, then showers likely with a chance of tstms through the night. A chance of showers after midnight. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ534-182000- Chesapeake Bay from Drum Point to Smith Point- 945 AM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH LATE TONIGHT... .REST OF TODAY...S winds 15 kt with gusts to 20 kt. Waves 2 to 3 ft. Areas of smoke with patchy fog late this morning. Scattered showers and tstms this afternoon. Vsby 1 to 3 NM late this morning. .TONIGHT...SW winds 10 to 15 kt...becoming W late. Gusts up to 20 kt. Waves 2 to 3 ft. A chance of showers and tstms. .SUN...NW winds 5 to 10 kt. Waves 1 to 2 ft. .SUN NIGHT...NE winds 5 to 10 kt. Waves 1 ft. .MON...E winds 5 to 10 kt. Waves 1 ft. .MON NIGHT...SE winds 10 to 15 kt. Waves 2 ft. Showers likely with a chance of tstms. .TUE...SW winds 15 to 20 kt. Waves 2 to 3 ft. Showers likely with a chance of tstms. .WED...SW winds 15 to 20 kt...becoming NW 10 to 15 kt. Waves 2 to 3 ft. A chance of showers in the morning, then showers likely with a chance of tstms through the night. A chance of showers after midnight. Winds and waves higher and visibilities lower in and near tstms. $$ ANZ543-182000- Tangier Sound and the inland waters surrounding Bloodsworth Island- 945 AM EDT Sat Jul 18 2026 ...SMALL CRAFT ADVISORY IN EFFECT THROUGH LATE TONIGHT... .REST OF TODAY...S winds 15 kt with gusts to 25 kt. Waves 1 to 2 ft. Areas of smoke with patchy fog late this morning. Scattered showers and tstms this afternoon. Vsby 1 to 3 NM late this morning. .TONIGHT...SW winds 10 to 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...becoming N 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 15 to 20 kt. Waves 1 to 2 ft...building to 3 ft. Showers likely 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 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. $$