Olsons Bay Weather Forecast
- 62
- 84
Mostly Sunny
- 61
- 83
Partly Sunny
- 60
- 78
Slight Chance Thunderstorms
- 62
- 78
Chance Rain Showers
- 62
- 79
Chance Thunderstorms
- 60
- 79
Chance Thunderstorms
Today 17 Sep Jefferson
Sunny. Highs in the mid 80s. South Winds up to 5 Mph.
Tonight 17 Sep Jefferson
Mostly clear. Lows in the lower 60s. Calm Winds.
Olsons Bay Temperature Statistics
September Temperature
Janesville-Rock County (17.4 miles)
Lowest 7 September, 2025
39.2 °FAverage September
59 °FHighest 14 September, 2025
84.2 °F
Climate (2020–Present)
Janesville-Rock County (17.4 miles)
Average Low 2020–2025
40.4 °FAverage 2020–2025
48.7 °FAverage High 2020–2025
60.2 °F