Great Lakes
Lake Ontario water temperature
Lake-average surface temperature 59.5 F (15.3 C) on Saturday, October 17, 2026.
- Lake Ontario lake-average surface water temperature is 59.5 F (15.3 C) as of , from NOAA GLERL's GLSEA analysis.
- That is 1.6 F cooler than a week earlier (61.1 F on ).
- On the same date last year Lake Ontario averaged 61.8 F.
- So far in 2026 the warmest day was 73.6 F on and the coldest 33.6 F on .
2026 (F)2025
Last 14 days
| Date | F | C |
|---|---|---|
| Oct 17 | 59.5 | 15.29 |
| Oct 16 | 60.0 | 15.53 |
| Oct 15 | 60.5 | 15.81 |
| Oct 14 | 60.7 | 15.95 |
| Oct 13 | 60.9 | 16.07 |
| Oct 12 | 61.0 | 16.10 |
| Oct 11 | 61.1 | 16.14 |
| Oct 10 | 61.1 | 16.19 |
| Oct 9 | 61.4 | 16.32 |
| Oct 8 | 61.6 | 16.46 |
| Oct 7 | 62.0 | 16.69 |
| Oct 6 | 62.5 | 16.95 |
| Oct 5 | 63.0 | 17.23 |
| Oct 4 | 63.5 | 17.49 |
Shore sensors and buoys near Lake Ontario
- BuffaloCO-OPS sensor · 60.6 F
- Cape VincentCO-OPS sensor · 56.7 F
- Alexandria BayCO-OPS sensor · 57.2 F
- OgdensburgCO-OPS sensor · 55.0 F
- Buoy 45012, EAST Lake America - 20NM North Northeast of Rochester, NY54.3 F
- Buoy 45135, Prince Edward Pt56.3 F
- Buoy 45159, NW Lake Ontario Ajax55.4 F
- Buoy 45215, Oswego, NY59.2 F
- Buoy BUFN6, 9063020 - Buffalo, NY60.8 F
- Buoy 4403586, Buffalo Buoy61.3 F
Source: NOAA GLERL Great Lakes Surface Environmental Analysis (GLSEA), daily lake-average surface temperature from satellite imagery. CSV of every day this year and last.