Lake Merwin Weather Forecast
- 51
- 73
Increasing Clouds
- 50
- 69
Partly Sunny
- 54
- 66
Mostly Cloudy
- 55
- 69
Partly Sunny
- 58
- 75
Mostly Sunny
- 57
- 80
Mostly Sunny
Today 18 Jul South Washington Cascade Foothills
Mostly sunny. Highs around 80. West wind 5 to 10 Mph.
Tonight 18 Jul South Washington Cascade Foothills
Partly cloudy. Lows around 50. Northwest wind 5 to 10 Mph.
Lake Merwin Temperature Statistics
July Temperature
Southwest Washington Regional Airport (22.4 miles)
Lowest 5 July, 2025
48 °FAverage July
67.3 °FHighest 13 July, 2025
95 °F
Climate (2020–Present)
Southwest Washington Regional Airport (22.4 miles)
Average Low 2020–2025
45 °FAverage 2020–2025
52.8 °FAverage High 2020–2025
62.3 °F