Portsmouth Harbor, Gangway Rocks LB13 — NH, United States

Tidal currents & slack water

↑1.4 kn↑1.6 kn↑1.3 kn02:3008:1814:4120:18Now
Tidal current at Portsmouth Harbor, Gangway Rocks LB13, computed from harmonic constituents. Maximum ebb of 2.0 knots on Mon 19 Oct 2026 at 23:01.
↑7:01am↓5:53pm

Predictions are not observations — conditions vary with weather and river flow. Not for navigation.

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Slack water and maximums for the next 7 days

Mon 19 Oct 2026 through Sun 25 Oct 2026. All times are local to Portsmouth Harbor, Gangway Rocks LB13 (America/New_York). What slack water is, and why it isn’t high or low tide.
DayCurrentTimeSpeed
Mon 19 Oct 2026Slack
Mon 19 Oct 2026Max flood1.4 kn
Mon 19 Oct 2026Slack
Mon 19 Oct 2026Max ebb1.6 kn
Mon 19 Oct 2026Slack
Mon 19 Oct 2026Max flood1.3 kn
Mon 19 Oct 2026Slack
Mon 19 Oct 2026Max ebb2.0 kn
Tue 20 Oct 2026Slack
Tue 20 Oct 2026Max flood1.5 kn
Tue 20 Oct 2026Slack
Tue 20 Oct 2026Max ebb1.8 kn
Tue 20 Oct 2026Slack
Tue 20 Oct 2026Max flood1.5 kn
Tue 20 Oct 2026Slack
Tue 20 Oct 2026Max ebb2.1 kn
Wed 21 Oct 2026Slack
Wed 21 Oct 2026Max flood1.6 kn
Wed 21 Oct 2026Slack
Wed 21 Oct 2026Max ebb2.1 kn
Wed 21 Oct 2026Slack
Wed 21 Oct 2026Max flood1.6 kn
Wed 21 Oct 2026Slack
Thu 22 Oct 2026Max ebb2.3 kn
Thu 22 Oct 2026Slack
Thu 22 Oct 2026Max flood1.9 kn
Thu 22 Oct 2026Slack
Thu 22 Oct 2026Max ebb2.5 kn
Thu 22 Oct 2026Slack
Thu 22 Oct 2026Max flood1.9 kn
Thu 22 Oct 2026Slack
Fri 23 Oct 2026Max ebb2.6 kn
Fri 23 Oct 2026Slack
Fri 23 Oct 2026Max flood2.1 kn
Fri 23 Oct 2026Slack
Fri 23 Oct 2026Max ebb2.9 kn
Fri 23 Oct 2026Slack
Fri 23 Oct 2026Max flood2.1 kn
Fri 23 Oct 2026Slack
Sat 24 Oct 2026Max ebb2.8 kn
Sat 24 Oct 2026Slack
Sat 24 Oct 2026Max flood2.4 kn
Sat 24 Oct 2026Slack
Sat 24 Oct 2026Max ebb3.3 kn
Sat 24 Oct 2026Slack
Sat 24 Oct 2026Max flood2.4 kn
Sun 25 Oct 2026Slack
Sun 25 Oct 2026Max ebb3.0 kn
Sun 25 Oct 2026Slack
Sun 25 Oct 2026Max flood2.5 kn
Sun 25 Oct 2026Slack
Sun 25 Oct 2026Max ebb3.6 kn
Sun 25 Oct 2026Slack
Sun 25 Oct 2026Max flood2.5 kn

Station facts

Position
43.0784° N, 70.7467° W
Time zone
America/New_York
Source
NOAA harmonic constituents
Region
NH, United States

How we check predictions — dated samples and their limits.

Nearby

All current stations