If you planning to travel to Lake Sammamish State Park, Issaquah, Washington, 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 3:24 PM. The temperature feels like 39.75 with a humidity level of 81 so dress accordingly. Cloud coverage is 69 percent with visibility at 12.4 percent. Today’s UV index is 3, don’t forget the sunscreen if you need it! Today’s winds are traveling south-southeast at a speed of 4 MPH. At the end of the day don’t miss the sunset at 1:20 AM.