West Coast
Mad River Slough
Arcata Bay · California · NOAA station 9418865 · Tide predictions
40.8650, -124.1480
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48-hour outlook
Drag across the curve to inspect any time. Weather icons show the forecast at each high tide.
Drawn from the high/low predictions — NOAA publishes high/low only for this station.
The next seven days
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H = high tide · L = low tide · highs & lows in local time
On the water nearby
Humboldt Bay, North Spit, CA (168) buoy · 11 mi W · Station 46244
Wind & wave reports →
Nearby tide stations
- Arcata Wharf · 1.9 mi SE
- Samoa · 3.1 mi SW
- Eureka Slough Bridge · 4.0 mi S
- Eureka · 4.1 mi S
- Bucksport · 6.5 mi SW
Plan ahead
2027 tide extremes for this station
Highest predicted high tide: 9.7 ft — Fri Jan 22 · 11:35 AM
Lowest predicted low tide: -2.4 ft — Sun Jun 6 · 8:25 AM
Biggest single-day swing: 11.5 ft on Fri Jan 22
Best daytime minus tides of 2027
| Date | Low tide | Height |
|---|---|---|
| Sun Jun 6 | 8:25 AM | -2.4 ft |
| Mon Jul 5 | 8:07 AM | -2.3 ft |
| Sun Jul 4 | 7:22 AM | -2.3 ft |
| Sat Jun 5 | 7:37 AM | -2.3 ft |
| Mon Jun 7 | 9:12 AM | -2.2 ft |
| Tue Jul 6 | 8:52 AM | -2.0 ft |
| Sat May 8 | 8:38 AM | -1.9 ft |
| Fri Jan 22 | 6:27 PM | -1.9 ft |
| Mon Aug 2 | 7:01 AM | -1.8 ft |
| Tue Jun 8 | 10:01 AM | -1.8 ft |
179 minus tides (below 0 ft) are predicted here in 2027. The table shows up to the 10 lowest that fall between 7 AM and 7 PM — the ones worth planning a clam dig or tidepool walk around.
About this station
NOAA builds the predictions for Mad River Slough, Arcata Bay from the HUMBOLDT BAY (North Spit) station: high tides about 1.12× the height, 43 min later; low tides about 1.07× the height, 35 min later.
Mixed semidiurnal tides — two unequal highs and two unequal lows a day — with ranges growing as you head north. Harbor entrances feel the swell as much as the tide.