Sumner Lake Weather Forecast
- 54
- 67
Isolated Thunderstorms
- 54
- 67
Slight Chance Thunderstorms
- 51
- 66
Mostly Sunny
- 50
- 59
Slight Chance Thunderstorms
- 54
- 62
Rain Showers Likely
- 53
- 65
Chance Rain Showers
- 50
- 63
Partly Sunny
Today 30 Jun Keweenaw
Mostly sunny. West Winds 5 to 15 Mph with Gusts up to 25 Mph.
Tonight 30 Jun Keweenaw
Mostly clear. Lows in the mid 50s. West Winds 5 to 10 Mph.
Sumner Lake Temperature Statistics
June Temperature
Copper Harbor (53.4 miles)
Lowest 14 June, 2025
39.7 °FAverage June
58.1 °FHighest 22 June, 2025
84.7 °F
Climate (2020–Present)
Copper Harbor (53.4 miles)
Average Low 2020–2025
38.5 °FAverage 2020–2025
44.6 °FAverage High 2020–2025
50.8 °F