Freestone · Mixed · Montana

Gallatin River

A wide, clear bend of the Gallatin River lined with pine trees and mountains in Montana.
Good · Rainbow Trout
Chubby Chernobyl · 6-10
Goodlive now
A proper day on the water
River lifting fast on the rain. Take your time — read the water before you cast.
65% confidence
What moved it
  • Level0.69 mLifting fast
  • Water temp12.3°C
  • ClarityVery colouredColouring up
Today's fly
Chubby Chernobyl
Chubby Chernobyl6-10
High-confidence seasonal pick
Conditions on the water
Live gauge
Level
Rising
0.69 m
Lifting fast
Water temp12.3°C
ClarityVery coloured
Weather12°C
WindSW 8 km/h
Pressure1019 hPa
Rain · recent3.1 mm
Rain · ahead0.2 mm

Live readings — water temperature is an estimate where the gauge does not record it.

Water temperature for Rainbow Trout
Ideal
12°C est.ideal 10–18°C
0°14°28°
How to fish it · for Rainbow Trout
When
Nymphing can work through most of the day.
Where
Cover mixed depths.
Method
Start with tight-line nymphs and adjust if fish rise or drift higher.
Kit
9 ft #4 rod, floating line, 12 ft tapered leader to 4–5 lb fluoro tippet.
Why this works
Good — water temperature is working for you, but insect activity is the limiting factor today.
Hatch timeline · todayQuiet day

Hatch predictions

Today's headline hatch shown — see all 2 active hatches hour by hour with Pro.

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Beyond the hatch · worth watchingambient prey

Hatch predictions

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Evidence
ModelledModerate confidence

Modelled from regional ecology — no survey or occurrence data for this water yet.

Through the year
0–3 scale · July highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
2
1
1
2
2
2
2
2
2
2
Western Green DrakeHatch
2
2
Flav (Small Western Green Drake)Hatch
2
3
2
Mahogany DunHatch
2
2
American March BrownHatch
2
3
2

Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.

Ranked for today
Rainbow Trout fly box
Permits & access
Permit required — see local rules.
  • Montana licence
  • No floating on most of the river — it is a wade fishery.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Hyalite Reservoir
31 km
Cutthroat trout · Brook trout
Madison River
38 km
Brown trout · Rainbow trout
Yellowstone River
40 km
24
Brown trout · Rainbow trout · Cutthroat trout
Ennis Lake
40 km
Brown trout · Rainbow trout
Quake Lake
48 km
Brown trout · Rainbow trout
Gallery · 2
  1. A wide, clear bend of the Gallatin River lined with pine trees and mountains in Montana.
    The Gallatin River curving through forested valley pastureland in Montana.
  2. Terrain map of the venue
    Terrain map
Water quality · US Clean Water Act
  • Aquatic life: Impaired
  • Recreation: Impaired
What this classification means

Recreation: Bacteria/pathogen advisory — mind wading cuts and immersion.

EPA ATTAINS assessment unit 'Gallatin River' (MT41H001_021), 2021 Integrated Report. Aquatic Life use: Not Supporting. Listed impairment causes: Algal Growth. This is a Clean Water Act assessment-unit classification (the US analogue of WFD), not a live reading.

Status is for the Clean Water Act assessment unit covering this reach.

EPA ATTAINS (Clean Water Act) · MT41H001_021

The full read · show the working · for Rainbow Trout · confidence 65%
How the 66 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow55 × 22%12.1
Clarity45 × 18%8.1
Feeding Time55 × 13%7.2
Pressure75 × 7%5.3
Insect activity44 × 12%5.3
Conditions total= 66
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
What would change the calculation
The dawn and dusk windows score higher than the midday lull.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • TroutThird Saturday of May → Last day of February
Related guides
Euro Nymphingsubsurface methods
Booking & contacts