Round Island Light — AK, United States

Tidal currents & slack water

↑1.5 kn↑0.7 kn↑0.5 kn07:5514:4919:27Now
Tidal current at Round Island Light, computed from harmonic constituents. Maximum flood of 0.5 knots on Mon 19 Oct 2026 at 17:16.
↑7:33am↓5:40pm

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 Round Island Light (America/Sitka). What slack water is, and why it isn’t high or low tide.
DayCurrentTimeSpeed
Mon 19 Oct 2026Slack
Mon 19 Oct 2026Max flood1.5 kn
Mon 19 Oct 2026Slack
Mon 19 Oct 2026Max ebb0.7 kn
Mon 19 Oct 2026Slack
Mon 19 Oct 2026Max flood0.5 kn
Mon 19 Oct 2026Slack
Mon 19 Oct 2026Max ebb1.1 kn
Tue 20 Oct 2026Slack
Tue 20 Oct 2026Max flood1.7 kn
Tue 20 Oct 2026Slack
Tue 20 Oct 2026Max ebb1.0 kn
Tue 20 Oct 2026Slack
Tue 20 Oct 2026Max flood0.9 kn
Tue 20 Oct 2026Slack
Tue 20 Oct 2026Max ebb1.3 kn
Wed 21 Oct 2026Slack
Wed 21 Oct 2026Max flood1.9 kn
Wed 21 Oct 2026Slack
Wed 21 Oct 2026Max ebb1.4 kn
Wed 21 Oct 2026Slack
Wed 21 Oct 2026Max flood1.4 kn
Wed 21 Oct 2026Slack
Thu 22 Oct 2026Max ebb1.5 kn
Thu 22 Oct 2026Slack
Thu 22 Oct 2026Max flood2.1 kn
Thu 22 Oct 2026Slack
Thu 22 Oct 2026Max ebb1.7 kn
Thu 22 Oct 2026Slack
Thu 22 Oct 2026Max flood1.8 kn
Thu 22 Oct 2026Slack
Fri 23 Oct 2026Max ebb1.8 kn
Fri 23 Oct 2026Slack
Fri 23 Oct 2026Max flood2.2 kn
Fri 23 Oct 2026Slack
Fri 23 Oct 2026Max ebb2.0 kn
Fri 23 Oct 2026Slack
Fri 23 Oct 2026Max flood2.2 kn
Fri 23 Oct 2026Slack
Sat 24 Oct 2026Max ebb2.0 kn
Sat 24 Oct 2026Slack
Sat 24 Oct 2026Max flood2.4 kn
Sat 24 Oct 2026Slack
Sat 24 Oct 2026Max ebb2.4 kn
Sat 24 Oct 2026Slack
Sat 24 Oct 2026Max flood2.6 kn
Sat 24 Oct 2026Slack
Sun 25 Oct 2026Max ebb2.2 kn
Sun 25 Oct 2026Slack
Sun 25 Oct 2026Max flood2.5 kn
Sun 25 Oct 2026Slack
Sun 25 Oct 2026Max ebb2.7 kn
Sun 25 Oct 2026Slack
Sun 25 Oct 2026Max flood2.9 kn

Station facts

Position
56.3142° N, 133.0940° W
Time zone
America/Sitka
Source
NOAA harmonic constituents
Region
AK, United States

How we check predictions — dated samples and their limits.

Nearby

All current stations