For all its charm, springtime in Paris is all about the weather.

It's impact is not just seen in outdoor cafe life but also directly on the 'terre batte' (clay) surface at Roland Garros. It means the interruptions in play are one factor in the complex matrix of surviving at the most arduous Grand Slam, as are the extreme variations in the playing conditions on French clay.

On a sunny and warm spring day the clay is fine and powdery, the base is firm and and surface relatively fine and high-bouncing, especially given the ball cover remains dry and undisturbed. Conversely, on cool and wet days such as those on Wednesday and Thursday, the top surface becomes wet and sticky (so sliding is more difficult), the base becomes soft underfoot, the balls collect moisture and the cloth starts unraveling and you can pick at the outer fibres.

This produces a very slow court with a lower bounce played with "heavier" balls due to the absorbed moisture content. Most players cannot wait for the balls changes at nine-game intervals.

What does this mean? Let's look at a prime example from last year where Robin Soderling took all before him as he swept past Rafael Nadal and Fernando Gonzalez to reach his first Grand Slam final, before being overcome by Roger Federer. Pundits understandably looked at that final and thought nerves played a part in the final result given that it was the imposing figure of Federer at the other side of the net.

But I beg to differ. The weather in Paris had changed dramataically. The quarter-finals and semi-finals were played in warm weather and Soderling's fine, flowing groundstrokes produced a stream of winners against the finest claycourt opposition. But the final was played in damp and cold conditions and the sting of Soderling's groundstrokes was absent. He was quickly disarmed by an opponent not with faster or heavier shots, but with more variety and subtlety - the low shots, changes of pace and a drop shot he used to describe as a cop-out. Soderling never really had a chance in those conditions.

Fast forward 12 months. Federer and Soderling are drawn to play each other in the quarter-finals and the way they're playing, I expect both men to be there. The big question is whether by next Tuesday the damp conditions are still prevalent or whether Paris returns to bathing in sunshine as was the case for the first two days. If it is the latter, then my prediction is that Federer's streak of 23 straight Grand Slam semi-final appearances (one I'm sure will last for 100 years) is under threat.

Soderling is fit, confident and striking the ball without peer. But he needs the weather gods to smile upon him for that one day, so we can sit back and let the beauty of the sport unfold.

It will be a contest for the connoisseurs and perhaps the moment a mighty streak will come to an end.