Castle Island Weather Forecast
- 39
- 49
Cloudy
- 44
- 55
Decreasing Clouds
- 42
- 57
Mostly Sunny
- 44
- 54
Slight Chance Rain Showers
- 47
- 54
Rain Showers Likely
- 47
- 56
Rain Showers Likely
- 44
- 56
Chance Rain Showers
Today 25 Apr Suffolk
Cloudy. Near steady temperature in the upper 40s. East Winds 5 to 10 Mph.
Tonight 25 Apr Suffolk
Cloudy. Lows in the upper 30s. Southeast Winds around 5 Mph, becoming southwest around 5 Mph after midnight.
Castle Island Temperature Statistics
April Temperature
Boston, Logan International Airport (1.2 miles)
Lowest 8 April, 2026
29.6 °FAverage April
50 °FHighest 14 April, 2026
78.7 °F
Climate (2021–Present)
Boston, Logan International Airport (1.2 miles)
Average Low 2021–2026
46.8 °FAverage 2021–2026
53.6 °FAverage High 2021–2026
61 °F