>>1994578you still have to go to work if it's raining, so prepare.
I'm middle aged now and have cycle commuted on and off since I was 16 in high school.
in my experience, full fenders and a rain cape are best in rain. the cape is open at the bottom like a poncho but shaped specifically for bike riding. that way, air circulates and it's not a sweat factory like an ordinary raincoat. the fenders keep off the water kicked up by your tires from the nasty ground . you stay completely dry and comfortable, and none of the dirty road spray gets on you , your drivetrain, and bike.
however, 15 minutes is cake, you could probably get away with an "ass saver" and a rain hat and windbreaker if you just want the minimum. if it comes down in buckets, you can always ride under an awning or thick tree cover near the trunk and wait out the worst.
if it makes you late, call the boss and say you caught a flat. rub grime from the rims on your hands for "proof".
speaking of, you need to learn how to change a flat and carry a patch kit and a small pump. it's easy and pretty quick once you've done it a few times.
for cold, your main enemy is the air /"wind" pulling all the warmth off of you as you speed through it (plus any actual wind on top of that.) modest warmth clothing under a windproof layer is all you need. keeping your (high from exercise) body heat inside the wind break will keep you toasty. if you wear winter coats under a wind break, you WILL overheat. wearing a few layers under the windbreaker allows for temperature regulation by removal if you get too hot.
again, 15 minutes is cake, so your body will probably be getting fully warmed up right when you arrive, so you may have more wiggle room for your clothing recipe
have fun! a bike ride always puts you in a good mood to start the day
