If you planning to travel to William O'Brien State Park, Marine on St. Croix, Minnesota, 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 1:15 PM. The temperature feels like 42.7 with a humidity level of 89 so dress accordingly. Cloud coverage is 85 percent with visibility at 9 percent. Today’s UV index is 1, don’t forget the sunscreen if you need it! Today’s winds are traveling south-southwest at a speed of 15 MPH. At the end of the day don’t miss the sunset at 10:38 PM.