If you planning to travel to Oso Flaco Lake, Arroyo Grande, California, 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 2:35 PM. The temperature feels like 49.65 with a humidity level of 91 so dress accordingly. Cloud coverage is 24 percent with visibility at 12.9 percent. Today’s UV index is 4, don’t forget the sunscreen if you need it! Today’s winds are traveling north-northwest at a speed of 13 MPH. At the end of the day don’t miss the sunset at 12:56 AM.