Tom Southam: A Tour Down Under full of surprises

'You don't need a weatherman to know which way the wind blows', sings the great Bob Dylan. That may be true, but what the weatherman knows might just be the key to this Tour Down Under.

In my job I am constantly trying to assess what is going to happen in events that have a seemingly endless list of variables. It is a bit like going and betting on the horses; you check the form guide, go through the details of the stages, previous winners, talk to people, and turn the whys and the whens over endlessly in your mind. Then though, instead of putting your money on someone else's gee-gee, you have to back your own, and work out ways for them to win.

If you were to look at the previous editions of the Tour Down Under, one thing that has been an almost constant factor throughout is the heat; Australia in summer, baking under an angry sun in a clear blue sky.

Before I sound too much like a whiny tourist who feels duped when the sun doesn't come out during an annual one-week package deal on the Costa del Sol, the heat does more than just make riders sunburnt and thirsty, it has an enormous influence on the way that a majority of the riders actually race the event.

In previous editions of the race the formula has been roughly the same on the opening stages: a couple of guys go early in the day and the peloton shuffles steadily along, regardless of the difficulties of the course, and the whole merry parade takes shape in time for a bunch sprint or a quick dash up the last ascent.

This can play perfectly in to the hands of the fast finishers, as the racing has to be done as late as is possible. Teams who have a sprinter are generally happy to ride a small break down because they would rather take a chance with a bunch kick and lose, than lose from a small group.

But this year I think we could be looking at a different race. The break survived today thanks in part to smart riding by those in the move, in part because of an untimely puncture for Geraint Thomas' puncture on the descent of Checker's Hill, and in part to the fact that the break simply wasn't completely cooked from riding through a cauldron all day.

A bike race is simply a product the environment that it is set in and the weather - as much as the terrain - is a crucial factor in that. We all know the route by now, reconnaissance and diligence sees to that, but with the temperatures set to dip through the week I think that we could well yet see a few more surprises.