Our experience last year in the latter part of September would drive the cruise packer nuts. We had cold damp rainy days in Vancouver , but also had two of five days at low 80's temps (even up in Whistler). Sailaway wa a raw , cold damp day. The poolside band wore woolen hats.
In Alaska we had cold damp and rainy weather in Juneau and the same for the morning in Skagway. In the afternoon we were at the summit in shirt sleeves and bright sun. Kettchican, where it rains 364and a half days a year was bright, sunny and 80degrees. Hubbard Glacier was windy, sleat and wet snow and 32 degrees.
Victoria BC was sunny and 75 degrees all day. We needed everything from Goretex jackets with hats and gloves to short sleeved shirts, all in 10 days.