If you planning to travel to Castle Island, Boston, Massachusetts, here is your 6-day travel weather forecast to make sure you have all the essentials needed during your stay. Start your day when the sunrises at 12:10 PM. The temperature feels like 2.5 with a humidity level of 50 so dress accordingly. Cloud coverage is 6 percent with visibility at 14.9 percent. Today’s UV index is 2, don’t forget the sunscreen if you need it! Today’s winds are traveling northwest at a speed of 14 MPH. At the end of the day don’t miss the sunset at 9:15 PM.