Lake Superior water temperature
Lake Superior, North Entry Buoy, North Keweenaw Peninsu · Lake
The current water temperature at Lake Superior is 17.1 °C (as of September 20, 2026, source: NOAA NDBC).
Lakes stratify in summer: bathing-warm on top, markedly colder a few metres down. Measurements are taken at the surface — right where you swim.
Water quality
Official EPA rating: excellentMeasurement series & statistics
This measurement series includes 1323 data points since July 22, 2026.
Lowest recorded value: 8.7 °C on September 5, 2026 · highest value: 20.3 °C on September 3, 2026.
In September, temperatures have ranged between 8.7 °C and 20.3 °C.
Nearby waters
More measuring points: Lake Superior
Frequently asked questions
Can you swim at Lake Superior right now?
The current water temperature is 17.1 °C. See live swimming conditions, weather and quality in the BrrChecker app.
How warm is the water at Lake Superior?
Currently 17.1 °C (updated continuously).
How warm is at Lake Superior in September?
In September, the water temperature recently averaged 17.1 °C.
When is the water warmest at Lake Superior?
Across the measurement record, July is on average the warmest month (18.4 °C).
How is the water quality at Lake Superior?
The official classification is: excellent.
