Wyoming ·
Firehole River Fly Fishing Report - December 12/3/2025
FIREHOLE RIVER FLY FISHING REPORT
Yellowstone National Park — Winter Field Update
Report Date: December 3, 2025 | Next Update: December 10, 2025
Current River Status & Regulations
Important — seasonal regulations in effect. As of early December the general Yellowstone fishing season has passed; the Firehole's summer access and use rules are no longer in effect and access on park roads is very limited. Before heading to the river confirm current restrictions and access with the National Park Service (Yellowstone) — conditions and closures change by season.
Open / Closed
Status (Dec 3, 2025): Limited / Seasonal. Many park roads and trailheads into the Firehole corridor are closed to vehicle traffic in winter; snowmobile and backcountry access may be permitted in specific areas. Check NPS updates for exact access windows.
Status (Dec 3, 2025): Limited / Seasonal. Many park roads and trailheads into the Firehole corridor are closed to vehicle traffic in winter; snowmobile and backcountry access may be permitted in specific areas. Check NPS updates for exact access windows.
Flows & Clarity
Typical late-fall/winter base flows — clear water with occasional turbidity near thermal vents. Expect excellent visibility where water is free-flowing; ice and frazil may form along edges.
Typical late-fall/winter base flows — clear water with occasional turbidity near thermal vents. Expect excellent visibility where water is free-flowing; ice and frazil may form along edges.
Water Temperature
Expected: near freezing in shaded reaches (32–40°F / 0–4°C). Thermal influence from geyser basins produces warm pockets; watch for water temperature stratification near hot springs.
Expected: near freezing in shaded reaches (32–40°F / 0–4°C). Thermal influence from geyser basins produces warm pockets; watch for water temperature stratification near hot springs.
Access Notes
Road access: variable (park road closures common). Parking and approach often require winter travel modes. Landings and wading may be icy — use microspikes and dress for wet cold conditions.
Road access: variable (park road closures common). Parking and approach often require winter travel modes. Landings and wading may be icy — use microspikes and dress for wet cold conditions.
Winter Hatch & Insect Activity
| Insect / Food Source | Size | Activity | Where to Target |
|---|---|---|---|
| Midges (adult & pupa) | #20–24 | Primary food — consistent (low-level) ⭐⭐⭐ | Slow tails, deep runs, behind boulders, near river margins |
| Baetis (small mayflies) | #18–22 | Light — sporadic afternoon rises on warmer days ⭐⭐ | Shallower riffles and foam seams on mild afternoons |
| Caddis | #16–20 | Uncommon — occasional evening activity ⭐ | Shoreline seams and riffle tails |
| Terrestrials / Stoneflies / Salmonflies | — | None — out of season | Not relevant in winter |
Recommended Flies (Winter-Focused)
Below are patterns matched to effective winter presentations on the Firehole. Each entry links to a shop pattern from the supplied fly sheet so you can review or order exact flies.
- Midge Patterns / Midges in the Drift — Black Zebra Midge (great for indicator nymphing and euro rigs): Black Zebra Midge (TBH); also consider Redneck Midge.
- Small Baetis / Emergers — Lightweight perdigons and baetis styles: Juju Baetis (Tungsten) and Top Secret Baetis.
- Tiny Nymphs / Point Flies — Perdigons & slim tungsten nymphs for tight, high-straight-line presentation: Olsen's Diabaetis Perdigon and Egan's Warrior Perdigon.
- Soft Hackles & Emergers — For subtle winter sipping fish: Soft Hackle Pheasant Tail (Jig) and Egan's Thread Frenchie Jig.
- Streamers (When fish are keyed on flesh) — Small sculpin and olive/ natural baitfish streamers for deeper lies: Sculpzilla - Olive, Coffey's CH Sparkle Minnow (Sculpin), and Tungsten Jig Bugger - Olive (barbless).
- Indicator / Strike Flies — Small tungsten tails to get down quickly: Pheasant Tail Tungsten and Tungsten Pat's Rubber Legs (use as a trailer or dropper where stonefly nymphs are expected).
- Eggs & Dirty Flies — On winter runs where fish are aggressive: Sunny Side Up - Sunburst and similar "slush egg" patterns.
Tactics, Rigs & Gear for December
Quick, practical strategies for winter Firehole fishing:
- Nymphing — Euro-style or indicator rigs with a small fast-sinking point fly (perdigon / tungsten nymph) and an attractor or dropper. Keep leaders short and tippets finer (5x–6x) where visibility is high.
- Midge Drifts — Long, drag-free drifts along slow tails and soft seams. A tiny midge under an indicator or an emerger close to the surface will outfish larger patterns in most winter conditions.
- Streamer Work — Slow strips through deep runs and holes. Use small articulated or weighted streamers on a sink-tip line when fish are holding deep.
- Presentation — In clear cold water, subtle equals success. Present drag-free drifts and avoid big, splashy entries. Short leader taper and small flies win more often than heavy tackle.
- Handling & Conservation — Handle fish quickly in cold water, minimize air exposure, and release gently. Cold-stressed fish are less resilient.
Safety, Logistics & Final Notes
Safety
Cold water + ice = real hazard. Wear non-slip boots, use a wading staff, and fish with a partner when possible. Hypothermia risk is real; pack extra dry clothing and hand warmers.
Cold water + ice = real hazard. Wear non-slip boots, use a wading staff, and fish with a partner when possible. Hypothermia risk is real; pack extra dry clothing and hand warmers.
Travel & Access
Many park roads are seasonally closed. If you plan a winter trip, check NPS Yellowstone updates and trail grooming reports. Snowmobile and backcountry travel require extra planning and permits where applicable.
Many park roads are seasonally closed. If you plan a winter trip, check NPS Yellowstone updates and trail grooming reports. Snowmobile and backcountry travel require extra planning and permits where applicable.
Regulations
Rules vary by reach and by season. Confirm current closures and special rules with Yellowstone National Park service pages before you go: NPS Yellowstone updates.
Rules vary by reach and by season. Confirm current closures and special rules with Yellowstone National Park service pages before you go: NPS Yellowstone updates.
