Jack London State Historic Park Weather Forecast
- 58
- 84
Chance Rain Showers
- 58
- 79
Decreasing Clouds
- 58
- 81
Mostly Sunny
- 60
- 86
Sunny
- 61
- 91
Mostly Sunny
- 59
- 82
Slight Chance Rain Showers
- 56
- 77
Mostly Sunny
Today 18 Sep North Bay Interior Valleys
Mostly cloudy late in the morning then becoming partly cloudy. A slight chance of Showers. Isolated Thunderstorms in the afternoon. Highs in the lower 70s to mid 80s. South Winds 5 to 15 Mph.
Tonight 18 Sep North Bay Interior Valleys
Mostly cloudy. Isolated Thunderstorms in the evening. A chance of Showers. Patchy fog after midnight. Lows in the mid 50s to lower 60s. Southwest Winds 5 to 10 Mph.
Jack London State Historic Park Temperature Statistics
September Temperature
Petaluma Municipal Airport (6.8 miles)
Lowest 14 September, 2025
48.2 °FAverage September
63.2 °FHighest 1 September, 2025
93.2 °F
Climate (2020–Present)
Petaluma Municipal Airport (6.8 miles)
Average Low 2020–2025
44.4 °FAverage 2020–2025
55.2 °FAverage High 2020–2025
69.1 °F