Montana · Hiking · Bob Marshall Wilderness

North Fk Sun

11.3 mi
round trip
283 ft
climb
5,423 ft
high point
Out and back
route
May–Sep
best months

Is North Fk Sun open right now?

Alert in the area

The Forest Service lists an alert for Rocky Mountain Ranger District.

As of · Source: USFS · Rocky Mountain Ranger District. Agencies don't list every closure — check before you go.

North Fk Sun is a hard hike in the Bob Marshall Wilderness, part of the Rocky Mountain Ranger District of Helena-Lewis and Clark National Forest in Montana. The Forest Service manages the land, and the trail is roughly 11 miles long with a total elevation gain of about 280 feet, making it an out-and-back that starts and ends at roughly 5,080 feet and reaches about 5,420 feet at the high point. Summer is the most comfortable time to go. Typical averages from the Gibson Dam weather station, about 10 miles away, show July highs near 79°F with lows around 45°F, and September still runs in the upper 60s by day. That station sits several hundred feet lower than the trail, so temperatures on the route run a little cooler. The trail is on natural surface, and the Forest Service lists it as not accessible. Horses are allowed, but bikes are not. The Cabin Creek Admin Connector starts just 0.1 mile away, and Moose Creek and Sulphur Creek are each within about a mile and a half. Mortimer Gulch Campground is about 9 miles away.

Local outfitters

Not on Roamze yet. Their page has how to reach them.

  • Best time to go · May–Sep

    Best time to visit North Fk Sun

    Best months: May–September. Best months have typical highs of 55–85 °F, lows of 30 °F or warmer (32 °F where the station doesn't record snow), at most one snowy day and no more than 12 wet days.

    1. Jan

      36° / 12°

      5 wet

    2. Feb

      36° / 12°

      6 wet

    3. Mar

      42° / 18°

      7 wet

    4. Apr

      50° / 25°

      7 wet

    5. May

      59° / 33°

      10 wet

    6. Jun

      67° / 39°

      10 wet

    7. Jul

      79° / 45°

      7 wet

    8. Aug

      78° / 43°

      6 wet

    9. Sep

      67° / 36°

      6 wet

    10. Oct

      54° / 29°

      6 wet

    11. Nov

      42° / 20°

      5 wet

    12. Dec

      35° / 13°

      5 wet

    Typical high / low (°F) and days with rain or snow, 1991–2020. Measured at Gibson Dam, MT, 9.9 mi away at 4,590 ft. The station sits about 800 ft lower than this place, so expect it a little cooler here. This station doesn't record snowfall. Source: NOAA NCEI U.S. Climate Normals 1991–2020.