Riding in the Rain in the summer is an acquired art. You can tell those who are new at it. They either looked like drowned rats or like poached eggs. Riding in the rain is something you need to learn if you live in an area like the Lower Mainland. We live in a rain forest; just because we cut down the trees we should still expect a lot of rain.
Invest in a riding shell. This water proof jacket will keep your torso dry and if you get one with underarm zippers to let out your body heat you will be glad you did. If you can’t let the heat out you will be wetter when you get there but it will be sweat.
Get rid of the jeans and sweat pants. You should never ride in jeans. The seam will give you a rash/burn if you do any serious riding and in the rain they can weigh more than your bike when they get wet. Sweat pants are even worse in the rain, guaranteed to give you plumber’s crack, which should be against the rules of the road.
For best results always ride in proper cycling shorts with the pad. Spandex is a beautiful thing when it’s not being stretched out of all proportion. In the winter use a pant shell but in the summer rain get your legs wet, it will cool you down and it actually feels pretty good if your jacket shell vents to let your heat out. A good fingerless glove will also give you more comfort than protection.
When you hit the hill make sure you vent your jacket before you start because heat will be your biggest problem as you try to keep your upper body dry. We can handle some heat but when you see some rider, who kept his jacket unvented all the way to the top of the hill, actually steam when he takes it off, only to be wetter than if he were riding nude.
So the goal is to get the ride in with some comfort and without catching the dreaded summer cold. The really issue is getting out there when you look out the window and its grey and dark with warm raining falling. Just put your mind ahead two hours and imagine how good it will be to stand in the same spot after your ride in the rain and know that you did it.