Weather for Walnut Creek Nature Park, CA - Walnut Creek Nature Park, CA Weather, Current Weather in Walnut Creek Nature Park, CA. Local weather report for Walnut Creek Nature Park, CA, Local Walnut Creek Nature Park, CA weather. Forecast for Walnut Creek Nature Park, California, Walnut Creek Nature Park, CA weather forecast. Find your local Walnut Creek Nature Park weather forecast. Walnut Creek Nature Park, CA weather conditions.