Mercedes driver Nico Rosberg has claimed his third consecutive pole position - an achievement never matched by his 1982 world champion father Keke, who won in Monaco 30 years ago - using the P Zero Red supersoft tyre, which is nominated with the P Zero Yellow soft this weekend. Rosberg's time of 1:13.876 was nearly half a second quicker than last year's pole time - set by Michael Schumacher in a Mercedes - and marked the fourth pole in a row for the team, after a thrilling session.

A sprinkling of rain half an hour before the start of Q1 meant that the track was damp for the first time all weekend. All the drivers started the opening session on the Cinturato Green intermediate tyre as the rain fell harder, before easing off in the closing minutes. The fastest driver in Q1 was Williams driver Pastor Maldonado, on the intermediate, while Caterham's Giedo van der Garde also used the intermediate to take his team into Q2 for the first time this year.

The rain continued in Q2, meaning that intermediates were once more the obvious choice. With just under five minutes to go the drivers began to switch to supersoft slick tyres, led by van der Garde. Red Bull's Sebastian Vettel was the fastest of the Q2 drivers on the supersoft, with a time set right at the end of the session.

The Q3 session was the only one where drivers were able to use slicks from the start, with all of them heading out on the supersoft. Pole position was decided in the closing seconds, with Rosberg taking pole from his team mate Lewis Hamilton.

Rosberg completed his domination of all the free practice sessions held at Monaco this year after going quickest by seven-tenths of a second in FP3 this morning on the P Zero Red supersoft.

Paul Hembery: "Qualifying got off to a tricky start as the drivers were immediately confronted with wet conditions for the first time all weekend in Q1, making it difficult to judge the amount of grip available - particularly as some parts of the circuit were much wetter than others. Generally we saw that the track got a lot quicker as each session went on, making the timing of each qualifying run absolutely crucial. As usual track position will be the key to a good result here tomorrow, but there is always scope to use a creative strategy to move further up the order. However, if the uncertain conditions continue tomorrow then the strategies will be blown wide open. We're still expecting to see more track evolution over the course of the weekend. Whether or not the drivers opt for one or two stops will depend on the speed of their cars and the track position they can maintain; we're not expecting wear or degradation to be a significant issue. Congratulations to Mercedes for a one-two on the grid; it will be interesting to see what they do with their strategies as they aim to convert this result into a race win."

The Pirelli mystery strategy predictor:

At Monaco, the strategy has to be very flexible in order to maintain track position and react to the high probability of a safety car at some point.

But theoretically, a two-stop strategy is quickest: start on the supersoft, change to the soft on lap 20 and soft again on lap 49.

An alternative strategy is a one-stopper, starting on the supersoft and moving to the soft on lap 36.

Another approach would be to start on the soft and change to the supersoft on lap 42.

Check out our Qualifying gallery, here.