← Lake Guide45.06° N · 108.11° W

Montana

Bighorn Lake

Roughly 12,423 acres of Montana water in Big Horn County, Bighorn Lake is a seasonal largemouth lake to read by cover and weather.

Surface
12,423acres
Primary species
Largemouth
§ 01Today on the water · Bighorn Lakevia Open-Meteo · 04:00 local
Air temp
69.0°F
Barometric
29.82″
→steady 24h(+0.02)
Wind
4mph
from NNW
Moon
Waxing Crescent
day 4.0 · 17% lit

Air conditions sampled near the lake center, not measured on the water · refreshed ~15 min

§ 03Next 3 daysvia Open-Meteo · interpretation
  1. 17
    julFri

    Stable window

    hi 90° · lo 63°

    Anytime through the day. Quiet weather day; lean on seasonal pattern and structure.

    ── light nw wind

  2. 18
    julSat

    Stable window

    hi 92° · lo 66°

    Anytime through the day. Quiet weather day; lean on seasonal pattern and structure.

    ── light nw wind · settled

  3. 19
    julSun

    Tougher window

    hi 95° · lo 68°

    Pick the calmest hour and stay flexible. Conditions push hard today; bite likely shrinks. Plan around the calmest gap.

    ── strong e wind · bite likely shrinks

§ 04Field notesMontana

Where it is

Bighorn Lake sits in Big Horn County, Montana, covering about 12,423 acres. Productive zones shift through the year more than the lake outline suggests.

Seasonal pattern

Spring. Bighorn Lake sits in Montana's short-season country — Big Horn County largemouth start late, staging when the protected water finally warms and spawning on the back end of spring.

Summer. Summer is brief and it's the season: across 12,423 acres, fish use cover hard while the water holds warmth, and consistent days cluster in the warmest stretch of the year.

Fall. Cool nights bite early at this latitude; the feeding window is real but short, and the taper comes fast.

Winter. Long, cold, and slow — the lake spends much of the year outside realistic largemouth conditions.

Key structure

  • Creek and cove mouths that funnel fish and bait
  • Weed edges and the clean lines along them
  • Inside turns where a bank changes angle
  • Submerged wood, brush, and laydown cover

The calendar decides which of these is worth time on a given day.

Forage

Forage on Bighorn Lake centers on baitfish and panfish; largemouth follow those schools across cover and depth changes.

Access

Access to Bighorn Lake is generally public; check water levels and conditions before launching.

Regulations

Check current state and local regulations before fishing; limits and seasons can change.

§ 05Sources & field guides

Field guides

Data & references

  • Today's conditions — Open-Meteo, refreshed every ~15 min
  • Moon phase — local astronomical calculation, no external API
  • Lake area, depth, structure — Identity, surface area, coordinates and county/state are from the ProjectD canonical waterbody index (snapshot conus-20260518-v1, group gnis:00793611). Maximum depth and regulation links were not available from an acceptable source and are intentionally omitted.
  • Regulations — verify current state and local regulations before fishing

Last revised · Back to Lake Guide