Best fishing time calculator

What is actually being calculated here?

Four things, scored separately and added up. There is no hidden weighting and no fitted coefficient, because there is no public catch-rate dataset to fit one against. Publishing the weights is the honest alternative to implying they came from somewhere they did not.

Note the asymmetry. Light level can reach +2 on its own and pressure can reach −2, while the two moon factors between them cap at +2 and can never go negative. That is not an oversight. Rising pressure behind a cold front genuinely spoils fishing often enough to justify a penalty; the moon being in the wrong place does not.

Where does this model’s data come from?

Sunrise, sunset and moon position come from Open-Meteo’s astronomy endpoints for the coordinates you pick. Barometric pressure is the station reading you enter, not a forecast we invent. The scoring weights themselves are editorial: they are published in the table above because there is no public catch-rate dataset that would let us fit them. Solunar periods are labeled traditional and unproven on purpose — see the next section. Verification dates for the astronomy source sit with the other tools on ourresearch methodology page.

When is this stretch of the Mississippi actually worth launching?

On Pool 8 the productive pattern we see most often is a falling barometer into a low-light window against the dam face or a current seam — the same combination that scores Prime in the worked example below. A bright midday behind a rising high is when we stay at the dock and check the gauge instead. For where to put the boat once the score looks good, use theGenoa stretch launch notes.

Why does light level carry the most weight?

Because it is the one factor here where the biology is not in dispute. Walleye have a reflective layer behind the retina called the tapetum lucidum that gives them a genuine advantage over their prey in dim water, which is why they hunt hardest at dawn, at dusk and after dark. Channel catfish feed largely by smell and taste and are most active through the night. Largemouth bass are sight feeders and concentrate their feeding in the low-light hours at either end of the day.

Three species, three different mechanisms, and the same practical answer: be on the water in the hour either side of sunrise or sunset. The model scores that window +2 and the middle of a bright day −1. When a fish does come in the net, thefish weight calculator turns its length into a weight range without inventing a single number.

How much should you trust the solunar part?

Very little, and the tool says so on the face of the result. Solunar theory holds that fish feed during major periods when the moon is directly overhead or directly underfoot. It has been in print since John Alden Knight published his tables in 1936 and it remains popular, but the controlled studies that have looked for the effect have not found a consistent one.

We kept it in, capped at one point, and labeled it "Traditional, unproven" everywhere it appears. Dropping it entirely would mean readers going elsewhere for a worse version of the same information. Weighting it like light level would be dishonest. One point, clearly marked, is the compromise.

Two worked examples

05:30 on 4 July 2026 at Brownsville, pressure falling

Sunrise that morning is 05:29, so 05:30 sits inside the low-light window and light scores +2. The moon is within an hour of underfoot, so the solunar factor adds its single point. A barometer down 2.5 hPa over three hours scores +2. Total +5, which the model calls Prime — the highest rating it gives, and a fair description of conditions any experienced angler on this river would pick out of a week.

Take the falling pressure away and the same morning scores +3, which is Good. One factor moved the verdict by a whole grade, which is roughly the influence a pre-front window deserves.

13:00 on 15 August 2026, high pressure behind a front

Sunrise was 06:10 and sunset is not until 20:09, so one in the afternoon is as far from either as you can get: light scores −1. Rising pressure scores −2. The moon is a 5 percent waxing crescent, near enough to new to earn its +1. Total −2, which the model calls Poor.

Worth stressing what that does and does not mean. People catch fish at one in the afternoon behind a cold front every single day of the summer. Poor describes the conditions, not your chances.

What do anglers get wrong about fishing forecasts?

Treating them as predictions is the main one. A conditions rating describes the water and the sky. It has no information about whether the fish in front of you are feeding, what they are feeding on, or whether your presentation is any good — which between them account for far more of the outcome than the barometer does.

Second is planning around the solunar table and ignoring sunrise. If a solunar major falls at eleven in the morning and sunrise was at half past five, the eleven o'clock window is the weaker bet by a wide margin, whatever the table says.

Third is reading a pressure number instead of a pressure trend. Absolute barometric pressure at 1015 hPa tells you almost nothing; the same reading falling fast and rising fast are opposite situations. That is why this tool asks which way it is moving rather than what it says.

Fourth is forgetting that timing only pays off if you are in the right place. ThePool 8 guide covers where to be at first light, which turns a Prime rating into an actual plan.