If you planning to travel to National Great Rivers Museum, Alton, Illinois, 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 12:50 PM. The temperature feels like 39.2 with a humidity level of 73 so dress accordingly. Cloud coverage is 60 percent with visibility at 12.4 percent. Today’s UV index is 1, don’t forget the sunscreen if you need it! Today’s winds are traveling northwest at a speed of 11 MPH. At the end of the day don’t miss the sunset at 10:40 PM.