Avalon on Catalina Island is known for its pleasant weather that makes fro dream vacations. When you visit, it's quite simple to pack a bag. All you need are some slack or jeans, shorts, a couple t-shirts or short & long sleeves, a jacket and swimsuit, just in case you decide to get wet in the Pacific Ocean. See average ocean temperatures.
The hottest temperature Catalina has ever experienced in recorded history is 104 degrees, a record that was set back in 1963. We've been to Avalon on some above average days and can attest that you need to keep a bottle of water with you to avoid dehydration during your hikes.
The island has plenty of restaurants and shops where you can purchase any food items and beverages you need to keep cool, but most the time the weather tends toward cool to pleasant.
Like so many Southern California coastal places, the hottest days during the summer only reach around 75 degrees on average, with evenings in the low 60s. Winter is quite pleasant, though some find it too cool for the hot vacations they seek. The average daytime temps in the winter hover around 65 to 68 degrees.