965
FZUS51 KLWX 181031
CWFLWX

Coastal Waters Forecast
National Weather Service Baltimore MD/Washington DC
631 AM EDT Tue Aug 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-
631 AM EDT Tue Aug 18 2026

.SYNOPSIS FOR THE TIDAL POTOMAC AND MD PORTION OF THE CHESAPEAKE BAY...

High pressure will gradually build in from the Ohio River Valley
through tonight while a weakening cold front stalls to the south
over the Carolinas. High pressure will move overhead Wednesday, then
 move offshore Wednesday night as a cold front approaches from the
Great Lakes. The cold front will cross the Mid-Atlantic Thursday,
then linger nearby Friday into the weekend as one or more waves of
low pressure ride along the front stalled near the coast.

$$

ANZ535-182000-
Tidal Potomac from Key Bridge to Indian Head-
631 AM EDT Tue Aug 18 2026

.TODAY...N winds 5 kt. Waves less than 1 ft.
.TONIGHT...NW winds around 5 kt. Waves 1 ft.
.WED...NW winds around 5 kt. Waves 1 ft.
.WED NIGHT...SW winds around 5 kt. Waves 1 ft or less.
.THU...NW winds around 5 kt. Waves 1 ft. Showers likely with a
chance of tstms.
.THU NIGHT...NE winds around 5 kt. Waves 1 ft. Showers likely.
.FRI...NE winds around 5 kt. Waves 1 ft. A chance of tstms through
the night. A chance of showers.
.SAT...SE winds around 5 kt. Waves 1 ft. A chance of showers in the
morning, then showers likely through the night. A chance of showers
after midnight.

Winds and waves higher and visibilities lower in and near tstms.

$$

ANZ536-182000-
Tidal Potomac from Indian Head to Cobb Island-
631 AM EDT Tue Aug 18 2026

.TODAY...NW winds 5 kt. Waves less than 1 ft. Isolated showers and
tstms this afternoon.
.TONIGHT...N winds around 5 kt. Waves 1 ft.
.WED...NW winds around 5 kt. Waves 1 ft.
.WED NIGHT...S winds around 5 kt. Waves 1 ft. A chance of showers.
.THU...SE winds around 5 kt. Waves 1 ft. Showers likely with a
chance of tstms.
.THU NIGHT...NE winds around 5 kt. Waves 1 ft. Showers likely with a
chance of tstms.
.FRI...NE winds around 5 kt. Waves 1 ft or less. A chance of showers
in the afternoon. A chance of tstms through the night. Showers
likely through the night.
.SAT...SE winds around 5 kt. Waves 1 ft. A chance of showers in the
morning, then showers likely through the night. A chance of showers
after midnight.

Winds and waves higher and visibilities lower in and near tstms.

$$

ANZ537-182000-
Tidal Potomac from Cobb Island to Smith Point-
631 AM EDT Tue Aug 18 2026

.TODAY...NW winds 5 kt. Waves less than 1 ft. Isolated showers and
tstms this afternoon.
.TONIGHT...N winds around 5 kt. Waves 1 ft or less.
.WED...NW winds around 5 kt. Waves flat.
.WED NIGHT...S winds around 5 kt. Waves 1 ft.
.THU...S winds around 5 kt. Waves 1 ft or less. Showers likely with
a chance of tstms.
.THU NIGHT...S winds 5 kt. Waves less than 1 ft. Showers likely with
a chance of tstms.
.FRI...NE winds 5 kt. Waves less than 1 ft. A chance of showers
through the day. A chance of tstms. Showers likely through the
night.
.SAT...SE winds 5 kt. Waves less than 1 ft. Showers likely. 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-
631 AM EDT Tue Aug 18 2026

.TODAY...N winds 5 to 10 kt. Waves 1 ft or less. Isolated showers
and tstms this afternoon.
.TONIGHT...NW winds around 5 kt. Waves flat.
.WED...W winds around 5 kt. Waves flat.
.WED NIGHT...SW winds around 5 kt. Waves flat.
.THU...NW winds around 5 kt. Waves flat. Showers with a chance of
tstms.
.THU NIGHT...N winds 5 to 10 kt. Waves 1 ft or less. A chance of
showers.
.FRI...NE winds 5 to 10 kt. Waves 1 ft or less. A chance of showers.
.SAT...E winds 5 kt. Waves flat. A chance of showers in the morning,
then showers likely through the night. A chance of showers after
midnight.

Winds and waves higher and visibilities lower in and near tstms.

$$

ANZ531-182000-
Chesapeake Bay from Pooles Island to Sandy Point-
631 AM EDT Tue Aug 18 2026

.TODAY...N winds 5 to 10 kt. Waves 1 ft. Isolated showers and tstms
this afternoon.
.TONIGHT...N winds around 5 kt. Waves 1 ft or less.
.WED...W winds around 5 kt. Waves flat.
.WED NIGHT...SW winds 5 kt. Waves flat.
.THU...W winds 5 kt. Waves flat. Showers likely with a chance of
tstms.
.THU NIGHT...N winds 5 to 10 kt. Waves 1 ft or less. A chance of
showers.
.FRI...NE winds 5 to 10 kt. Waves 1 ft. A chance of tstms in the
afternoon. A chance of showers.
.SAT...E winds 5 kt. Waves less than 1 ft. A chance of showers in
the morning, then showers likely.

Winds and waves higher and visibilities lower in and near tstms.

$$

ANZ538-182000-
Patapsco River including Baltimore Harbor-
631 AM EDT Tue Aug 18 2026

.TODAY...N winds 5 kt. Waves flat.
.TONIGHT...NW winds around 5 kt. Waves flat.
.WED...W winds 5 kt. Waves flat.
.WED NIGHT...SW winds 5 kt. Waves flat.
.THU...E winds 5 kt. Waves flat. Showers likely with a chance of
tstms.
.THU NIGHT...N winds 5 kt. Waves flat. A chance of showers.
.FRI...NE winds around 5 kt. Waves 1 ft or less. A chance of
showers.
.SAT...E winds 5 kt. Waves less than 1 ft. A chance of showers.

Winds and waves higher and visibilities lower in and near tstms.

$$

ANZ539-182000-
Chester River to Queenstown MD-
631 AM EDT Tue Aug 18 2026

.TODAY...N winds 5 kt. Waves less than 1 ft. Isolated showers and
tstms this afternoon.
.TONIGHT...N winds around 5 kt. Waves flat.
.WED...W winds around 5 kt. Waves flat.
.WED NIGHT...SW winds around 5 kt. Waves flat.
.THU...NW winds around 5 kt. Waves flat. Showers likely with a
chance of tstms.
.THU NIGHT...NE winds around 5 kt. Waves 1 ft or less. Showers
likely.
.FRI...NE winds 5 to 10 kt. Waves 1 ft or less. A chance of showers
in the afternoon. A chance of tstms through the night. Showers
likely through the night.
.SAT...E winds 5 kt. Waves flat. A chance of showers in the morning,
then showers likely.

Winds and waves higher and visibilities lower in and near tstms.

$$

ANZ532-182000-
Chesapeake Bay from Sandy Point to North Beach-
631 AM EDT Tue Aug 18 2026

.TODAY...N winds 5 to 10 kt. Waves 1 ft. Isolated showers and tstms
this afternoon.
.TONIGHT...N winds around 5 kt. Waves 1 ft or less.
.WED...W winds 5 kt. Waves flat.
.WED NIGHT...SW winds 5 kt. Waves less than 1 ft. A chance of
showers.
.THU...NW winds 5 kt...becoming E in the afternoon. Waves 1 ft.
Showers likely with a chance of tstms.
.THU NIGHT...NE winds 5 to 10 kt. Waves 1 ft. Showers likely.
.FRI...NE winds 5 to 10 kt...becoming E after midnight. Waves 1 ft.
A chance of showers in the afternoon. A chance of tstms through the
night. Showers likely through the night.
.SAT...E winds 5 to 10 kt...becoming SW after midnight. Waves 1 ft.
A chance of showers in the morning, then showers likely through the
night. A chance of showers after midnight.

Winds and waves higher and visibilities lower in and near tstms.

$$

ANZ540-182000-
Eastern Bay-
631 AM EDT Tue Aug 18 2026

.TODAY...N winds 5 to 10 kt. Waves 1 ft. Isolated showers and tstms
this afternoon.
.TONIGHT...N winds around 5 kt. Waves flat.
.WED...NW winds around 5 kt. Waves flat.
.WED NIGHT...SW winds around 5 kt. Waves 1 ft or less. A chance of
showers.
.THU...W winds around 5 kt. Waves flat. Showers likely with a chance
of tstms.
.THU NIGHT...NE winds around 5 kt. Waves 1 ft or less. Showers
likely.
.FRI...NE winds 5 to 10 kt. Waves 1 ft or less. A chance of showers
in the afternoon. A chance of tstms through the night. Showers
likely through the night.
.SAT...SE winds 5 kt. Waves less than 1 ft. Showers likely.

Winds and waves higher and visibilities lower in and near tstms.

$$

ANZ533-182000-
Chesapeake Bay from North Beach to Drum Point-
631 AM EDT Tue Aug 18 2026

.TODAY...N winds 5 to 10 kt. Waves 1 ft. Isolated showers and tstms
this afternoon.
.TONIGHT...N winds around 5 kt. Waves 1 ft or less.
.WED...NW winds around 5 kt. Waves 1 ft or less.
.WED NIGHT...S winds 5 kt. Waves less than 1 ft. A chance of
showers.
.THU...S winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance
of tstms.
.THU NIGHT...SE winds 5 to 10 kt...becoming NW after midnight. Waves
1 ft. Showers likely.
.FRI...NE winds 5 to 10 kt...becoming E after midnight. Waves 1 ft.
A chance of showers in the afternoon. A chance of tstms through the
night. Showers likely through the night.
.SAT...SE winds 5 to 10 kt...becoming SW after midnight. Waves 1 ft.
Showers likely. A chance of showers after midnight.

Winds and waves higher and visibilities lower in and near tstms.

$$

ANZ541-182000-
Choptank River to Cambridge MD and the Little Choptank River-
631 AM EDT Tue Aug 18 2026

.TODAY...N winds 5 to 10 kt. Waves 1 ft. Isolated showers and tstms
this afternoon.
.TONIGHT...N winds around 5 kt. Waves 1 ft or less.
.WED...NW winds around 5 kt. Waves 1 ft or less.
.WED NIGHT...S winds around 5 kt. Waves 1 ft. A chance of showers.
.THU...SW winds 5 kt. Waves less than 1 ft. Showers likely with a
chance of tstms.
.THU NIGHT...SE winds 5 kt...becoming NW after midnight. Waves 1 ft.
Showers likely.
.FRI...NE winds 5 to 10 kt...becoming E after midnight. Waves 1 ft.
A chance of showers through the day. A chance of tstms through the
night. Showers likely through the night.
.SAT...SE winds 5 kt. Waves less than 1 ft. Showers likely.

Winds and waves higher and visibilities lower in and near tstms.

$$

ANZ542-182000-
Patuxent River to Broomes Island MD-
631 AM EDT Tue Aug 18 2026

.TODAY...N winds 5 kt. Waves less than 1 ft. Isolated showers and
tstms this afternoon.
.TONIGHT...N winds around 5 kt. Waves 1 ft.
.WED...NW winds around 5 kt. Waves 1 ft.
.WED NIGHT...S winds around 5 kt. Waves 1 ft. A chance of showers.
.THU...S winds around 5 kt. Waves 1 ft. Showers with a chance of
tstms.
.THU NIGHT...S winds around 5 kt. Waves 1 ft. Showers likely with a
chance of tstms.
.FRI...NE winds around 5 kt. Waves 1 ft. A chance of showers through
the day. A chance of tstms through the night. Showers likely through
the night.
.SAT...SE winds around 5 kt. Waves 1 ft. Showers likely. 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-
631 AM EDT Tue Aug 18 2026

.TODAY...N winds 10 kt. Waves 1 ft. Isolated showers and tstms this
afternoon.
.TONIGHT...N winds 5 to 10 kt. Waves 1 ft.
.WED...NW winds 5 kt. Waves less than 1 ft.
.WED NIGHT...S winds 5 to 10 kt. Waves 1 ft.
.THU...S winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance
of tstms.
.THU NIGHT...S winds 5 to 10 kt. Waves 1 ft. Showers likely with a
chance of tstms.
.FRI...N winds 5 to 10 kt...becoming E. Waves 1 ft. A chance of
showers through the day. A chance of tstms. Showers likely through
the night.
.SAT...S winds 5 to 10 kt. Waves 1 ft. Showers likely.

Winds and waves higher and visibilities lower in and near tstms.

$$

ANZ543-182000-
Tangier Sound and the inland waters surrounding Bloodsworth Island-
631 AM EDT Tue Aug 18 2026

.TODAY...NW winds 5 to 10 kt. Waves 1 ft. Isolated showers and tstms
this afternoon.
.TONIGHT...N winds 5 to 10 kt. Waves 1 ft or less.
.WED...NW winds 5 kt. Waves flat.
.WED NIGHT...S winds 5 to 10 kt. Waves 1 ft.
.THU...SW winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance
of tstms.
.THU NIGHT...S winds 5 to 10 kt. Waves 1 ft. Showers with a chance
of tstms.
.FRI...N winds 5 to 10 kt...becoming E. Waves 1 ft. A chance of
showers through the day. A chance of tstms. Showers through the
night.
.SAT...S winds 5 to 10 kt. Waves 1 ft. Showers, mainly in the
morning.

Winds and waves higher and visibilities lower in and near tstms.

$$