If you want to continue enjoying your riding you need good waterproof kit like this ION 3-Layer Traze Amp short from German brand Ion.
The ION 3-Layer Traze Amp short uses a thick, multi-layer, waterproof and breathable fabric that is also stretchable in four directions for extra mobility. The material is rated at 20,000mm for waterproofness and 20,000g/m/24hr for breathability; both of which are impressively high compared to most of the competition. Lab results don’t always carry over to the real world but the Traze has proved waterproof and windproof, with no boil-in-the-bag effect, even on milder, wetter, splashy rides.
Fit and adjustment are good, but, like many biking shorts, the waistband is a little big as most keen mountain bikers have a larger butt and thighs than average. It’s easy to cinch it tighter though via an elasticated Velcro strap that’s thick and stiff enough to hold the slippery fabric tightly.
Fully seam-sealed inside, Ion’s short is very flexible and comfortable next to your skin. There are two, flap-protected and zipped hip pockets, one with a neoprene sleeve that keeps your phone secure and reasonably dry too, but the zip isn’t fully waterproof.
With leak-free waterproofing, a durable fabric that fits great and covers kneepads if needed, the ION 3-Layer Traze Amp short is an excellent waterproof short. Top-level performance is reflected in a top-tier price of £145 but that’s about all I can question here.