Tri'ing in the rain, any tips and advice?

Enjoy!  I've run my best races in the rain!  The cooler temps mean I don't get dehydrated, and by practicing riding in the rain, I felt more confident about where to speed, where to apply my brakes.  I saw myself passing people in rainy races, where I would NEVER do this in sunny races.  My two cents: wear eye gear and either a light jacket or arm warmers for the bike (so the rain doesn't spike you as you push through).  Run - you could try for dry pair of socks (depending on how hard it is raining).  In transition, wrap your whole bag inside a trash bag (to keep things dry), and bring another trash bag to stow all your soppin' wet gear after your done.  Most importantly, bring warm, dry cozy clothes for the finish. 

Thanks for posting this because I was wondering the same thing for this weekend biathlon (although we are suppose to have a rain/snow mix).  I am worried about the bike portion too.  Lots of hills and at least one tight turn at the bottom of a big hill.

I saw the suggestion about eye wear for the bike.  I usually wear my contact lenses when I bike in the rain normally because my glasses get wet and I can't see.  Why the eye gear?

 Because having rain pelt you in the eyes going 30km/h sucks .

My last race was in miserable MISERABLE weather.  My feet froze on the bike, so I'd recommend booties or something if it's going to be cold.  They warmed up about 1km into the 5km run.  I also wore a base layer toque (beanie - call it what you will) under my helmet on the bike which made things a bit less miserable, even if I looked a bit goofy. 

Wear your running tights over your tri shorts if you have them...I was very glad for the warmth.  Have a decent pair of warm gloves for the bike.  I wore neoprene and it wasn't ideal, but they were all I had so that was that.

In some ways it was great, but mostly it sucks (in my opinion) - I never thought I'd be wanting to get BACK into the pool...until that race. 

 Since its a sprint you probably want to figure what you're going to wear the whole race. Unless you don't care at all about your transition times changing you clothes really eats up time.

Unless its really cold you may consider just some arm warmers and possibly a vest shell. If you have a wetsuit you can wear the armwarmers underneath it. They're gonna get wet anyway.

Remember that road shoes are really slippery so be careful if you have to run in your bike shoes.

The bike will be the most hazardous obvously. Try not to ride on painted lines(slippery) metal grates(really slippery) dirt or mud(slippery and may fling gunk), reflectors(slippery) oil(really, really slippery). Anything that isn't asphalt will probably be slippery. Try to stay in the saddle. If you stand up to pedal uphill your rear wheel may slip. Brake early and stay relaxed. Its okay to slow wayyyy down for a turn. Pedaling will keep you center of gravity low so even on downhills or spooky sections keep your pedals going. If you have to ride through something slippery then go straight at a moderate speed and spin while feathering your speed with the brakes. keeping the wheels and pedals turning help keep you upright.

The good news is bike tires like to grip asphalt even when its wet. As long as the roads aren't sloppy traction shouldn't be a problem.

On the run try not to step in puddles. soaked feet are heavy and prone to blisters.

Make sure you have dry stuff to wear after the race!!!!

If you stay alert and relaxed you should be fine. You biggest enemy will be being all tense because of the unfamiliar conditions.

My 2 cents but I would defer to anyone from British Columbia

Use a plastic tote for your stuff in transition.  Trash bags are ok in a pinch, but they can blow around and be harder to find stuff in.  Get a nice little rubbermaid type tote thingy and when you pop the lid off everything is right there for you to see/grab.  It's also an easy way to carry your stuff to/from the car.

Do not try, AVOID PAINTED LINES AT ALL COSTS!  Trust me, I learned the hard way (on my two week old Cervelo Dual )

Also watch your hydration. I tend to drink less when being pelted by  water from the sky.

This is one area I wish I less experience in. Maybe  2007 ?!?!?!??!?

Someone already suggested glasses, even if it's not sunny.  Clear or amber lenses can be ideal. 

I'd also suggest a hat for the run.  The brim keeps more rain off the glasses (easier to see) and prevents drops from coming down behind my glasses and hitting my eyes.

Wear your wet suit while setting up transition.  You might start a trend.  Take plastic bags for each leg of the race.  One bag for your bike gear, one for your run gear.

I have had some of my best times in races when it is raining.

It is a challenge

If you want theory, ask a physicist.  If you want to do a track stand, apply force to your pedals.