2011 Canadian Grand Prix The Canadian Grand Prix

Vettel starts backing the pack up at the exit of the Turn 10 hairpin.

With only a little experience of Pirelli's wets from testing and no wet running this weekend, the crossover point from wets to inters or even slicks is a total unknown.

The safety car will pit at the end of this lap.

Onto a fourth lap behind the safety car.

"It's okay, it's wet but normal," reports Hamilton over the McLaren radio.

Meantime, the squall line is getting ever-closer to the circuit, as it approaches from the west. There will be a period of moderate to heavy rainfall for a time, when it arrives.

The leaders come through to complete a second safety car lap. Still no indication of it coming in.

Alguersuari of course has a full wet set-up on the Toro Rosso. His first challenge will be to negotiate his way past the Virgin and HRT cars.

Massa's engineer Rob Smedley informs the Brazilian that further heavy rain is expected 15 minutes into the race.

Alonso runs slightly wider at Turn 2, assessing the grip on the outside.

Vettel completes lap one behind the safety car.

In-car cameras suggest visibility is tough but not impossible.

Paul di Resta squirts the throttle exiting Turn 8 and discovers there is little grip, as the rear end of the Force India steps out.

Race control sends out the official message confirming DRS is disabled due to the weather.

Puddles at the Turn 3/4 chicane look mostly off-line.

Jaime Alguersuari is released from the end of the pitlane and he joins the back of the queue.

There is plenty of spray being kicked up as the field heads through the fast corners at the start of the lap.

The safety car moves away and Sebastian Vettel begin to forward as the first lap of the race begins.

As this is a wet race, DRS use is banned until the FIA declare otherwise.

The engines fire into life with less than one minute to go.

Fernando Alonso has his visor up and is looking around at the condition of the track from the cockpit of the Ferrari.

Track temperature is 20 degrees with an ambient of 19 Celsius. It is not raining currently.

There are five minutes to go until the start of the Canadian Grand Prix.

A developing squall line with heavy showers is building just to the west of the city. It is expected to arrive around an hour into the race.

That means the extreme wet tyre is mandatory for everyone and no one can gamble on intermediates.

The race will start behind the safety car.

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A huge crowd is gathered at the circuit and they rise in unison to respect the national anthem, 'Oh Canada', as it is played out over the public address system.

The pits are now closed. Any driver not on the grid by now, will be required to start behind the rest of the field.

Here is the grid line-up for today's race: Pos Driver Team 1. Sebastian Vettel Red Bull-Renault 2. Fernando Alonso Ferrari 3. Felipe Massa Ferrari 4. Mark Webber Red Bull-Renault 5. Lewis Hamilton McLaen-Mercedes 6. Nico Rosberg Mercedes 7. Jenson Button McLaren-Mercedes 8. Michael Schumacher Mercedes 9. Nick Heidfeld Renault 10. Vitaly Petrov Renault 11. Paul di Resta Force India-Mercedes 12. Pastor Maldonado Williams-Cosworth 13. Kamui Kobayashi Sauber-Ferrari 14. Adrian Sutil Force India-Mercedes 15. Sebastien Buemi Toro Rosso-Ferrari 16. Rubens Barrichello Williams-Cosworth 17. Pedro de la Rosa Sauber-Ferrari 18. Jaime Alguersuari Toro Rosso-Ferrari 19. Jarno Trulli Lotus-Renault 20. Heikki Kovalainen Lotus-Renault 21. Tonio Liuzzi HRT-Cosworth 22. Timo Glock Virgin-Cosworth 23. Narain Karthikeyan HRT-Cosworth 24. Jerome D'Ambrosio Virgin-Cosworth

Poleman Sebastian Vettel tells TV interviewers that the track will be too wet for intermediates at the start.

The rain appears to have stopped all around the circuit, but the track remains wet and will certainly be wet for the first stint of the race.

Sebastian Vettel has arrived on the grid and taken up his pole position slot. He climbs out of the car and will continue discussion with his race engineer.

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Toro Rosso has opted for a full wet set-up change, prompting a pitlane start for the Spaniard.

Jaime Alguersuari will start today's race from the pitlane.

Here's a reminder of the standings after six rounds: World Championship standings, round 6: Drivers: Constructors: 1. Vettel 143 1. Red Bull-Renault 222 2. Hamilton 85 2. McLaren-Mercedes 161 3. Webber 79 3. Ferrari 93 4. Button 76 4. Renault 50 5. Alonso 69 5. Mercedes 40 6. Heidfeld 29 6. Sauber-Ferrari 21

Jenson Button has gone to the grid on a set of intermediate tyres.

Nick Heidfeld is wheeled back into the garage after one checking lap. The team may want to make another change before he goes out again.

Rubens Barrichello

Conditions were damp and drizzly from the word go this morning, but in the last hour the conditions have deteriorated.

A band of rain coming in from the south-west has produced some heavier pulses and the track is soaked as we build up to the race.

The rain is expected to stay in a wet or damp condition at least until half-distance - and it may be wet all the way through depending how long it takes for this latest band of rain to pass over the city.

Temperatures have cooled dramatically with the arrival of the rain, with a maximum of just 17 degrees Celsius this afternoon.