Lowland · Mixed · Yorkshire / Vale of Pickering

River Derwent (Yorkshire)

River Derwent (Yorkshire) terrain map
Poor · Brown Trout
Pheasant Tail Nymph · 14-16
Poorlive now
Not the day for it
River temperature is the limiting factor today, not the flow. This is not the day to push it. Check the thermal advice above before you head out.
90% confidence
What moved it
  • LevelProxyvia River Rye
  • Water temp24.8°C
  • ClarityClear
Today's fly
Pheasant Tail Nymph
Pheasant Tail Nymph14-16
Upstream, sub-surface
Conditions on the water
Proxy gauge
Level
Steady
Proxy
via River Rye
Water temp24.8°C
ClarityClear
Weather25°C
WindW 11 km/h
Pressure1016 hPa
Rain · recent0.0 mm
Rain · ahead0.0 mm

No gauge on this water — conditions are inferred from River Rye. The trend transfers, the absolute level does not.

Water temperature for Brown Trout
Welfare risk
25°C est.ideal 10–16°C
0°14°28°
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
Water at 24.8°C. This is the line where catch-and-release kills brown trout. Do not fish for them today.
Sub-surface · on the nymphunder the surface

Hatch predictions

Top nymph shown — see all 3 guilds with Pro.

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Beyond the hatch · worth watchingambient prey

Hatch predictions

Top prey shown — see all 3 with Pro.

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Evidence
Survey-backed · regionalHigh confidence

Backed by regional invertebrate surveys; no sampling on this exact reach yet.

Through the year
0–3 scale · August highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
2
1
Grayling seasonSeason
2
2
1
1
2
2
2
2
2
2
Daddy Long LegsHatch
2
3
2
Terrestrial BeetlesHatch
2
3
3
2
Blue Winged OliveHatch
1
2
2
2
2
1
Black MidgeHatch
1
2
2
2
2
2
2
2
2
2
2
1

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

Ranked for today
Brown Trout fly box
Permits & access
Permit required — see local rules.
  • Club-controlled game water; day-ticket and membership access varies by beat
  • Grayling club season closes 31 December (earlier than the statutory 14 March)
  • Check the controlling club before travelling.
What's coming
Plan ahead
5-day outlook
Water here around 25°C. Nothing cooler within range — carry a thermometer.
The full read · show the working · for Brown Trout · confidence 90%
How the 0 is built — score × weight = contribution
Temperature0 × 28%0.0
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time70 × 13%9.1
Pressure80 × 7%5.6
Insect activity51 × 12%6.1
Limiting factor: Water temperature (24.8°C) is outside Brown Trout's preferred range (10–16°C)= 56
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowproxy via River Ryeproxy
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout 25 March → 30 September
  • Grayling 16 June → 14 March

    Statutory grayling season is 16 June – 14 March, but the controlling clubs close grayling fishing on 31 December — earlier than the statutory date. Plan a winter grayling visit before the turn of the year, and confirm current club rules before travelling.

    Club water closes 31 December — earlier than the legal 14 March.

    Prime sport 1 October → 31 December

Related guides
Grayling Playbookgrayling tacticsTrout Near Londonaccess guideEuro Nymphingsubsurface methods
Casting instructors near here
Booking & contacts