Crystal Lake Weather Forecast
- 55
- 76
Mostly Sunny
- 55
- 76
Partly Sunny
- 54
- 75
Partly Sunny
- 55
- 71
Slight Chance Rain Showers
- 55
- 76
Mostly Sunny
- 49
- 76
Mostly Sunny
- 49
- 69
Partly Sunny
Today 14 Sep Sullivan
Sunny. Highs in the upper 70s. North Winds around 5 Mph.
Tonight 14 Sep Sullivan
Mostly clear. Areas of fog. Lows in the lower 50s. Northeast Winds around 5 Mph.
Crystal Lake Temperature Statistics
September Temperature
Williamsport - Lycoming County Airport (14.3 miles)
Lowest 8 September, 2025
44.1 °FAverage September
63.7 °FHighest 5 September, 2025
82 °F
Climate (2020–Present)
Williamsport - Lycoming County Airport (14.3 miles)
Average Low 2020–2025
43.8 °FAverage 2020–2025
53 °FAverage High 2020–2025
63.3 °F