If you planning to travel to Caernarfon Castle, Caernarfon, Wales, United Kingdom, 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 8:31 AM. The temperature feels like 48.1 with a humidity level of 86 so dress accordingly. Cloud coverage is 52 percent with visibility at 14.9 percent. Today’s UV index is 0, don’t forget the sunscreen if you need it! Today’s winds are traveling south-southwest at a speed of 20 MPH. At the end of the day don’t miss the sunset at 4:11 PM.