Thunder Lake
49.7788° N, 92.6633° W
Depth contours from the government survey. Not for navigation.
Download the depth map (SVG)Thunder Lake, Ontario. 49.7788° N, 92.6633° W
Maximum depth 21.3 m. Scale bar on the map.
Not for navigation. Depths are from government surveys and may be outdated.
borealbound.ca/lakes/on/thunder-lake/, compiled October 9, 2026
- Canadian Geographical Names Database, Natural Resources Canada. Contains information licensed under the Open Government Licence – Canada.
- HydroLAKES v1.0, Messager et al. 2016 / WWF HydroSHEDS. Licensed under CC BY 4.0.
- Census boundaries and population, 2021, Statistics Canada. Adapted from Statistics Canada. This does not constitute an endorsement by Statistics Canada.
- Aquatic Resource Area survey points, Ontario Ministry of Natural Resources. Contains information licensed under the Open Government Licence – Ontario.
- Fishing access points, Ontario Ministry of Natural Resources. Contains information licensed under the Open Government Licence – Ontario.
- Fisheries Management Zones, Ontario Ministry of Natural Resources. Contains information licensed under the Open Government Licence – Ontario.
- Lake Partner Program, Ontario Ministry of the Environment, Conservation and Parks. Contains information licensed under the Open Government Licence – Ontario.
- Bathymetry lines and survey index, Ontario Ministry of Natural Resources. Contains information licensed under the Open Government Licence – Ontario.
- City page weather forecasts and alerts, Environment and Climate Change Canada. Contains data from Environment and Climate Change Canada (ECCC Data Servers End-use Licence).
- Guide to Eating Ontario Fish: Advisory Database, Ontario Ministry of the Environment, Conservation and Parks. Contains information licensed under the Open Government Licence – Ontario.
Thunder Lake is 21.3 m deep at its deepest point, deeper than 62% of the 2,688 surveyed lakes in Ontario. It covers 11.2 km² and lies 4.9 km east of Dryden.
Government surveys have recorded 15 fish species here, including walleye, northern pike and yellow perch.
- Maximum depth
- 21.3 m
- deeper than 62% of the 2,688 surveyed lakes in Ontario
- Area
- 11.2 km²
- larger than 96% of the 18,731 lakes in Ontario
- Shoreline
- 20.4 km
- longer than 88% of the 18,731 lakes in Ontario
- Water clarity
- 3 mSecchi depth, 2019
- less clear than 64% of the 1,251 monitored lakes in Ontario
- Fish species
- 15
- more than 91% of the 2,454 surveyed lakes in Ontario
- Elevation
- 372 m
Today on the water
3.8 °C
Observed at Dryden, as of 2:00 a.m. CDT
choppy Estimated waves, next 12 hours: up to 0.2 m. Around 10 a.m., wind from the south: the south shore is sheltered, waves build toward the north shore.
| Time | 3 a.m. | 6 a.m. | 9 a.m. | 12 p.m. | 3 p.m. | 6 p.m. | 9 p.m. | 12 a.m. |
|---|---|---|---|---|---|---|---|---|
| Wind km/h | SE 10 | S 10 | S 10 | S 20 | SE 15 | SE 20 | SE 20 | SE 20 |
| Gusts km/h | 40 | 40 | ||||||
| Waves (est.) m | 0.1 | 0.1 | 0.1 | 0.2 | ||||
| Temp. °C | 3 | 1 | 5 | 10 | 11 | 11 | 11 | 10 |
| Precip. % | 20 | 20 | 20 | 20 | 30 | 30 | 10 | 10 |
Tonight: Partly cloudy. Becoming clear this evening. Wind northwest 30 km/h gusting to 50 becoming light this evening. Low plus 1.
Weather: Dryden (local forecast), as of 2:01 a.m. CDT
Sun and moon
- Civil dawn
- 6:50 a.m.
- Sunrise
- 7:23 a.m.
- Sunset
- 6:31 p.m.
- Civil dusk
- 7:03 p.m.
- Moonrise
- 6:16 a.m.
- Moonset
- 5:50 p.m.
- Moon
- Waning crescent, 1% lit
Follow this lake by email: a weekly summary of conditions.
Depth
21% of Thunder Lake is shallower than 3 m, and 52% is deeper than 10 m.
How to read it: the lake’s area is sorted from the shore to the deepest point. Where the curve is flat, large areas share one depth (flats and weed beds); where it drops, depth changes quickly (drop-offs).
The government depth survey records a maximum depth of 21.3 m, drawn from 13 depth contours.
- Download the depth map (SVG)Printing this page gives the map on one sheet, with scale and sources.
Not for navigation. Depths are from government surveys and may be outdated.
Fish
Sport fish by the share of the 33 government surveys (2010–2010) that recorded them.
Forage fish and other species (6)
Forage fish
- Spottail Shiner 10
- Trout-Perch 8
- Mimic Shiner 7
- Logperch 5
- Slimy Sculpin 2
Other
- White Sucker 14
Numbers are the surveys that recorded each species.
Eating your catch
The provincial guide to eating fish (2026) sets limits for 7 species from Thunder Lake. Maximum meals per month:
| Species | Length | General population | Sensitive population* | Contaminant |
|---|---|---|---|---|
| Lake Trout | 50-55 cm | 8 | 4 | Mercury |
| Lake Whitefish | 45-50 cm | 16 | 8 | Mercury |
| Northern Pike | 55-60 cm | 4 | Do not eat | Mercury |
| Smallmouth Bass | 35-40 cm | 8 | Do not eat | Mercury |
| Walleye | 40-45 cm | 12 | 4 | Mercury |
| Burbot (Ling) | 50-55 cm | 8 | Do not eat | Mercury |
| White Sucker | 40-45 cm | 16 | 12 | Precautionary |
* As defined in the guide, including children and people who are or may become pregnant. Limits are for the length the guide lists most often; they change with the size of the fish. Read the official guide
Fishing regulations: Fisheries Management Zone 5. Check seasons and limits before you fish.
Water
Getting on the water
1 listed boat launch. marks launches on the map.
- Boat launch
Follow this lake
Every Friday by email: the Environment Canada forecast and any weather alerts in effect.