computer bag rain cover AquaQuest Storm 100% Waterproof Laptop Sleeve – Lightweight Ripstop Nylon Case, Welded Seams and Removable 5 mm Neoprene Liner – 15 in – Black – Fits up to 15 × 11 in : Electronics Leather Color:Black Embossed Croc Cowhide Leather The Final Word - Notice that if your KATE SPADE

computer bag rain cover AquaQuest Storm 100% Waterproof Laptop Sleeve – Lightweight Ripstop Nylon Case, Welded Seams and Removable 5 mm Neoprene Liner – 15 in – Black – Fits up to 15 × 11 in : Electronics Leather Color:Black Embossed Croc Cowhide Leather The Final Word - Notice that if your KATE SPADE

The Final Word - AmazonBasics 55L Backpack Review - YouTube

I recommend this even with a waterproof bag, so maybe Osprey is onto something by not including a rain cover with their pack

KATE SPADE

Leather Color:Black Embossed Croc Cowhide Leather

This plastic pouch from REI makes an excellent alternative and fits easily into any bag when it’s empty and rolled up

Notice that if your laptop is not among these models