Fishing report
Big Missouri Lake Rock Bass Fishing Report
Prairie du Chien, WI
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Modeled from live National Weather Service data as of Aug 27, 2026 at 2:12 AM CDT, plus solunar and sun/moon times computed in-house. This is a computed report, not an eyewitness catch report.
Big Missouri Lake has no state survey naming Rock Bass. Its presence is an estimate inferred from 8 confirmed lakes within 40 miles — not a record of a catch.
Overall rating
Rock Bass at Big Missouri Lake — 2026-08-27
Fair · 50/100Best window: 1 AM (Good · 61/100)
- Season
- Summer
- Moon
- 99% illuminated, waxingFull Moon
- Est. surface temp
- 74.8°F
- Pressure
- 30.01 inHgRising
Est. water temp
74.8°F
v1 estimate from air temperature — not a sensor reading
Below Rock Bass's 80-87°F range
Air vs. last week
2°F warmer
61°F now vs 59°F this time last week
Measured air temperature at the nearest weather station — not water
Sun & moon
- Sunrise
- 6:23 AM
- Sunset
- 7:47 PM
- Moonrise
- 7:38 PM
- Moonset
- 5:41 AM
Sky, wind & pressureat best window · 1 AM
- Cloud cover
- 2%
- Precip chance
- 0%
- Wind
- 0 mph
- Pressure
- 30.01 inHg Rising
Species context
Why this score
Fair (50/100) for Rock Bass: water is estimated at 74.8°F, below Rock Bass's 80-87°F optimal range. Best window: Night — boosts feeding activity by about 30%. That hour also overlaps a major solunar period. 30.01 inHg and rising pressure modeled about 5% below this fish's baseline. Calm (0-5 mph) wind modeled about 10% below this fish's baseline.
What's driving the 1 AM score
Water temperature (74.8°F estimated) is doing the most for this score. The score gives up the most on water temperature — 74.8°F estimated, about 13.9 points below its best. The whole day is then scaled to 75% for post-cold-front high.
- Water temperature · neutral
- Light window · helping
- Solunar period · helping
- Barometric pressure · helping
- Wind · helping
Show the numbers behind this
Water temperature: 74.8°F estimated
26.1 of 40 pts
Optimal range 80-87°F
Well supportedWater temperature governs a cold-blooded fish's metabolism, so it is the largest term in the model (Christie & Regier 1988). The figure is a thermal-lag estimate built from forecast air temperature and the time of year — not a sensor reading, and not this lake's actual measured water.
Light window: Night
23.2 of 25 pts
Boosts feeding activity by about 30%
Well supportedLow-light feeding windows are the strongest timing signal inside a single day. How much each window is worth is this species' own cited response, sourced in its model file, not a generic curve.
Solunar period: Major period
15 of 15 pts
Not supported by testingPeer-reviewed testing of North American freshwater fisheries found no significant relationship between solunar values, lunar phase or lunar illumination and catch rates (SN Applied Sciences, 2023) — air temperature predicted catch better than any solunar table tested. It is shown because anglers expect it, and it is shown separately so you can discount it. Its weight is under owner review.
Barometric pressure: Stable (held neutral by the front)
9.5 of 10 pts
Modeled flat — no change from this fish's baseline
ContestedThe barometric effect is real to most anglers but small and contested in the literature — several of the species studies cited in this model report null results — so it carries one of the smallest weights here.
Wind: Calm (0-5 mph)
7.8 of 10 pts
Modeled about 10% below this fish's baseline
Moderately supportedWind stacks forage on windward structure, but both the size and the direction of the effect depend on the species and the water, so it carries a modest weight.
Then the whole score is scaled
Season: Summer — ×1.00 (100% of the ungated score)
How catchable Rock Bass are at this point in the year. This scales the whole score rather than competing with the factors above — a fish that is dormant this time of year cannot score well no matter how good the hour looks.
Weather front: Post-cold-front high — ×0.75 (75% of the ungated score)
A multi-hour frontal pattern read from the day's forecast trajectory. Because a front IS a barometric event, it replaces the single-reading pressure factor above, which is held neutral — the barometer is never counted twice.
Those five factors add up to 81.7 of 100 points, and the two multipliers above take that to 61. The weights are v1 tuning constants under owner review — they are shown here rather than hidden so you can weigh them against your own judgement.
What this score does not know
- Water clarity. We have no source for it and do not estimate it.
- Measured water temperature. The figure in the breakdown is a model over forecast air temperature, not a reading from a buoy or a probe.
- Baitfish and forage activity.
- How much fishing pressure this water has had.
- Where the fish actually are. Depth bands are the species' published seasonal ranges, not an observation of this lake.
- What anyone actually caught. No catch reports feed this score.
Conditions read from the National Weather Service as of Aug 27, 2026 at 2:12 AM CDT. Solunar periods and sun/moon times are computed, not fetched.
When best caught
It's currently summer. Rock Bass typically hold 5-15 ft deep this time of year — at an estimated 74.8°F, this looks like a slower time of year to target them, since water temp is outside their optimal range.
Current depth
5-15 ft
This is the seasonal depth band from the species model — relative to this species' typical behavior, not this lake's actual structure. True depth relative to this lake's bottom contours needs lake bathymetry (tracked in issue #175).
Today's solunar periods
- Major: 11:24 PM–1:24 AM
- Minor: 5:11 AM–6:11 AM
- Major: 11:46 AM–1:46 PM
- Minor: 7:08 PM–8:08 PM
Best times
When do rock bass feed during the day?
Rock Bass feed most actively at Dusk, when activity runs about 22% above the daily average across all four light windows.
- Dawn1.30x
Boosts feeding activity by about 30%.
- Daytime0.60x
Suppresses feeding activity by about 40%.
- Dusk1.40x
Boosts feeding activity by about 40%.
- Night1.30x
Boosts feeding activity by about 30%.
Hour by hour
Hourly bite forecast
| Hour | Bite score | Rating | Light | Wind |
|---|---|---|---|---|
| 1 AM | 61 | Good | Night | 0 mph |
| 2 AM | 53 | Fair | Night | 1 mph W |
| 3 AM | 53 | Fair | Night | 1 mph W |
| 4 AM | 53 | Fair | Night | 1 mph NW |
| 5 AM | 57 | Fair | Night | 1 mph NW |
| 6 AM | 57 | Fair | Dawn | 1 mph NW |
| 7 AM | 53 | Fair | Dawn | 0 mph |
| 8 AM | 44 | Fair | Day | 1 mph NW |
| 9 AM | 44 | Fair | Day | 1 mph N |
| 10 AM | 44 | Fair | Day | 2 mph N |
| 11 AM | 52 | Fair | Day | 3 mph N |
| 12 PM | 52 | Fair | Day | 3 mph N |
| 1 PM | 52 | Fair | Day | 3 mph N |
| 2 PM | 44 | Fair | Day | 3 mph N |
| 3 PM | 44 | Fair | Day | 3 mph NW |
| 4 PM | 44 | Fair | Day | 3 mph N |
| 5 PM | 44 | Fair | Day | 2 mph NW |
| 6 PM | 44 | Fair | Day | 1 mph NW |
| 7 PM | 47 | Fair | Day | 0 mph |
| 8 PM | 58 | Fair | Dusk | 0 mph |
| 9 PM | 53 | Fair | Night | 0 mph |
| 10 PM | 53 | Fair | Night | 0 mph |
| 11 PM | 53 | Fair | Night | 0 mph |
Where to find Rock Bass right now
Typical Summer depth: 5-15 ft
Rock Bass feed most actively at Dusk, when activity runs about 22% above the daily average across all four light windows.
No depth survey or measurement is on record for Big Missouri Lake, so these bands are the species' published seasonal ranges rather than a reading of this water.
Plan a Rock Bass trip to Big Missouri Lake
Change the date, compare species, or check the week ahead in the live tool.
Other species on record at Big Missouri Lake
FAQ
Common questions
Are there Rock Bass in Big Missouri Lake?
Big Missouri Lake has no state survey naming Rock Bass. Its presence is an estimate inferred from 8 confirmed lakes within 40 miles — not a record of a catch.
When do Rock Bass bite at Big Missouri Lake?
Rock Bass feed most actively at Dusk, when activity runs about 22% above the daily average across all four light windows. Today's report above scores every hour of the local day against live weather for Big Missouri Lake, and shows what each input contributed alongside how well the evidence supports it.
How deep should you fish for Rock Bass at Big Missouri Lake?
Typical Rock Bass depth by season: Pre-Spawn 2-5 ft, Spawn 1-4 ft, Post-Spawn 3-8 ft, Summer 5-15 ft, Fall 5-15 ft, Winter 8-20 ft. These bands come from published fisheries data for the species, not from a survey of Big Missouri Lake itself.