Tailwater · Mixed · Montana, US

Ruby River

Ruby River near Twin Bridges January 2015 01
Today · About as good as it gets
Czech Nymph
Forecast · Today
About as good as it gets
On the feed top to bottom — start on the rises with a dry, drop a nymph if they stay down.
90% projected
Today's fly
Czech Nymph
Czech Nymph
Conditions on the water · Today
Live gauge
Level
Falling
0.74 m
Dropping after lift
Water temp11.2°C
ClarityClearing
Weather9°C
WindN 9 km/h
Pressure1024 hPa
Rain · recent0.0 mm
Rain · ahead0.0 mm

The nearest gauge doesn't record temperatures, so we've estimated it — defer to the river keeper's advice.

Water temperature for Brown Trout
Ideal
11°C est.ideal 10–16°C
0°14°28°

Typical for this reach at this time of year, fitted to the river's own record — not a reading of today's release. A change at the dam can move it several degrees within hours. It also warms as it runs away from the dam.

How to fish it · for Brown 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
Excellent — conditions well-balanced, with water temperature particularly in your favour.
Likely species
Mayflies
Chironomids
Gammarids
Hatch timeline · todayPeak at 11 Uhr

12 Uhr(now) — Western Blue-Winged Olive

Stage: On emergersApproach: Emerger or dryActivity: 71%
Also:Black Midge39%
Peak emergence window6 food groups active

Peak activity at 11 Uhr — Western Blue-Winged Olive (Western Blue-Winged Olive, Peak emergence window)

Sub-surface · on the nymphunder the surface

Hatch predictions

Supporters see the full sub-surface read.

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Beyond the hatch · worth watchingambient prey(1)

Hatch predictions

Top prey shown — see all 3 as a supporter.

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Evidence
Records-basedModerate confidence

Based on species-occurrence records, not local invertebrate surveys.

Through the year
0–3 scale · October 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 Blue-Winged OliveHatch
2
3
3
3
3
3
3
3
2
Pale Morning DunHatch
2
3
3
2
TricoHatch
2
3
2
Black MidgeHatch
2
3
3
3
3
3
3
3
3
3
3
2

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

Ranked for today
Fly box · Brown Trout
Permits & access
Permit required — see local rules.
  • Montana licence
  • Small, brushy, irrigation-controlled; access is contentious — verify before fishing.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Madison River
30 km
75
Brown trout · Rainbow trout
Jefferson River
33 km
81
Brown trout · Rainbow trout
Ennis Lake
35 km
Brown trout · Rainbow trout
Beaverhead River
50 km
87
Brown trout · Rainbow trout
Big Hole River
52 km
75
Brown trout · Rainbow trout · Brook trout
Gallery · 2
  1. Ruby River near Twin Bridges January 2015 01
  2. Terrain map of the venue
    Terrain map
Water quality · US Clean Water Act
  • Aquatic life: Impaired
What this classification means

EPA ATTAINS assessment unit 'Ruby River' (MT41C001_010), 2021 Integrated Report. Aquatic Life use: Not Supporting. Listed impairment causes: Temperature, Sediment, Nutrients, Habitat Alterations, Hydrologic Alteration. 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) · MT41C001_010

The full read · show the working · for Brown Trout · confidence 90%
How the 86 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time75 × 13%9.8
Pressure80 × 7%5.6
Insect activity68 × 12%8.2
Conditions total= 86
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout Dritter Saturday im May → Letzter day of February
Related guides
Euro Nymphingsubsurface methods
Booking & contacts