STIKINE — GRAND CANYON · window opens when Telegraph Creek drops under 550 cms

OPEN since Jul 30 · 423 and holding under 550

Odds it's still runnable on Sep 17: 87%. Rain re-closes this window in 4 of 10 years — the sky gets a vote. Fly-in windows: watch the rain, not the calendar.

423 cms · ↓ falling under 550 — open gauge data through Aug 18 ↗

This year against the last 10

P95–max

P90–95

P75–90

P25–75 · half of years

P10–25

P5–10

min–P5

this year

median

550/300 window

draw a year:

Today's 423 cms sits at the 60th percentile for Aug 18. Hover or touch for any date's numbers; tap a year below to draw it. Where the black line drops inside the green dashes, the canyon opens.

Next 10 days in the basin

basin headwaters · issued Aug 19, Open-Meteo

Wed

11°2°

avg 11°/4°

dry

Thu

14°2°

avg 10°/4°

dry

Fri

13°4°

avg 10°/4°

2.5 mm rain

Sat

10°4°

avg 9°/3°

1.9 mm rain

Sun

7°3°

avg 9°/3°

7.4 mm rain

Mon

9°3°

avg 9°/3°

3.3 mm rain

Tue

9°4°

avg 9°/3°

3.3 mm rain

Wed

10°4°

avg 9°/3°

4.5 mm rain

Thu

8°6°

avg 9°/2°

10.8 mm rain

Fri

10°5°

avg 9°/2°

1.2 mm rain

High/low at the basin headwaters (upper Stikine + Iskut, the points the model uses). The faint avg is the 1991–2020 normal for the date. Rain runs straight off; snow banks in the alpine — so a cold, snowy storm barely moves the river while a warm, rainy one lifts it fast.

Next 10 days at Dease Lake

Dease Lake (town, staging) · issued Aug 19, Open-Meteo

Wed

18°7°

avg 16°/8°

0.5 mm rain

Thu

21°7°

avg 16°/8°

dry

Fri

22°8°

avg 15°/7°

0.8 mm rain

Sat

18°9°

avg 15°/7°

0.2 mm rain

Sun

15°8°

avg 15°/7°

1.8 mm rain

Mon

16°9°

avg 14°/7°

2.7 mm rain

Tue

15°10°

avg 14°/7°

3.0 mm rain

Wed

18°10°

avg 14°/6°

3.0 mm rain

Thu

16°11°

avg 14°/6°

3.0 mm rain

Fri

20°10°

avg 14°/6°

dry

The town most crews stage from — warmer and lower than the headwaters above. This is what to pack for, not a flow signal: Dease Lake drains north to the Liard, over the divide from the Stikine.

Odds the window is open, day by day

From here on it's pure reclose risk — historical years that opened near our date, matched to today's status. Orange: inside a 7+ day window; blue: reclosed. As of Aug 18.

The watch log

Jul 30 window opened — gauge crossed under 550
Jul 26 opens ~Aug 05 ±8 d
- gauge near the line (568 cms) — model lands near Aug 05
Jul 20 opens ~Aug 11 ±11 d
- gauge still above the line (713 cms) — model lands near Aug 11
Jul 19 opens ~Aug 07 ±11 d
- gauge still above the line (737 cms) — model lands near Aug 07
Jul 16 opens ~Aug 03 ±11 d
- gauge still above the line (693 cms) — model lands near Aug 03
Jul 15 opens ~Aug 10 ±14 d
- gauge still above the line (699 cms) — model lands near Aug 10
Jul 08 opens ~Aug 08 ±17 d
- gauge running high (896 cms) — model lands near Aug 08
Jul 04 opens ~Aug 16 ±16 d
- gauge running high (941 cms), but a cold, dry July — model lands near Aug 16
Jul 03 opens ~Aug 12 ±16 d
- cool but unusually dry July
- dry wins: less rain means a faster drop
Apr 01 odds only
- season outlook opened
- this canyon runs on summer glacier-melt and rain, so the first dated call lands Jul 1 with real melt data in hand

This season on the gauge

Flags mark every 550 crossing after the peak. Rain re-closes this window in 4 of 10 years — the opening is forecastable; whether it stays open depends on the fall rain.

When each season first dropped under 550

Every dot a season’s first opening under 550, 1954–2026 · orange = it faded out (dropped low, no reclose) · blue = rain pushed it back over 550 at least once. Hover for the year.

Snow in the bank — not in the model

Forrest Kerr (high) 11 yrs from 2015 · peaked 1927 mm May 19 · now 1180 mm, 272% of the Jul 9 normal

Tumeka Creek (mid) 32 yrs from 1989 · peaked 639 mm Apr 21 · melted out (normal for the date)

Kinaskan Lake (valley) 32 yrs from 1990 · peaked 487 mm Apr 12 · melted out (normal for the date)

Snow-water at three elevations, each against its own history over the melt season. The high station (Forrest Kerr) holds into summer and feeds the late river; the valley is bare by June. We checked and it does not cleanly predict the opening date, so it is context, not a model input — but a deep, slow-melting high snowpack tends to hold the river up longer.

What goes into this call — and where to check it yourself

Flow: Stikine at Telegraph Creek (Water Survey of Canada 08CE001), 71 years of record + live · BC River Forecast Centre
Weather: Basin temp & rain (ERA5 via Open-Meteo) · 16-day forecast models · seasonal ensemble out to October
History: Every recorded season's post-opening flow, spliced into the odds curve — the 4-in-10 rain reclose risk is included in the curve
Snow: Not in the call — 70 years of backtesting show snowpack adds no predictive skill to the 550 opening date. Live telemetry: Forrest Kerr high elevation (Iskut headwaters), Kinaskan Lake and Tumeka Creek are melted out (BC automated snow stations, live).

These are forecasts, not gauge readings. Check the live gauge before you commit to travel. Seen a run come in? Let us know — real dates improve next year's forecast.