How solunar fishing windows work
Solunar tables predict the times when fish and game are supposedly most active, based on the position of the moon. Here is exactly how FishTideTimes calculates them, and how much weight to give them.
Major and minor windows
- Major windows (about 2 hours) are centred on the moon’s upper transit (moon highest in the sky, “overhead”) and lower transit (moon on the opposite side of the Earth, “underfoot”).
- Minor windows (about 1 hour) are centred on moonrise and moonset.
Because the moon rises about 50 minutes later each day, the windows drift later day by day. There are usually two majors and two minors, but on some days one of them falls just outside midnight-to-midnight and the day has only three.
How we compute them
Sun and moon positions are calculated in your browser from standard astronomical formulas (after J. Meeus, Astronomical Algorithms) for the station’s exact latitude and longitude, including the moon’s parallax. In our tests the results are within about two minutes of the U.S. Naval Observatory for sunrise and sunset and within about three minutes for moonrise, moonset and transit. Times are shown in the station’s local time, with daylight saving applied.
The star outlook
Each day gets 1–4 stars from two simple rules:
- Moon phase: days within about two days of a new or full moon score higher. These are also spring tides, with the biggest tidal range and strongest currents.
- Light: a major or minor window within an hour of sunrise or sunset adds to the score, because dawn and dusk are reliably productive for many species.
That’s it — no hidden “secret sauce”. We show the rules so you can judge for yourself.
What the evidence says
Scientific support for solunar theory is mixed. Some studies of angler catch records find modest moon-phase effects for certain species; others find none. What is well established is that moving water, light level, water temperature and bait drive feeding in coastal fish. Use the windows as a tie-breaker between otherwise similar days, and put tide movement first.
Tides first
For most inshore fishing, the two to three hours around a tide change, when current is building or easing, are the most productive. Many anglers prefer the last of the incoming tide on flats and the outgoing tide at inlets and creek mouths, where bait is flushed out. Slack water can be slow at the inlet but good for fishing structure that is unfishable in strong current.