Ominous grey skies over Silverstone and persistent rain set up the prospect of an unpredictable, if not chaotic, British Grand Prix on Sunday. Leading drivers forecast problems with possible aquaplaning and \'a long tough race\' on the slippery circuit. Defending double world champion Sebastian Vettel, who starts fourth for Red Bull, said: \"It could be a big lottery with conditions like that. \"It will be a tough day. Now it\'s raining again! It will be a long race.\" After a brief respite from the downpours on Saturday when championship leader Fernando Alonso secured pole position for Ferrari, Sunday arrived with more of the torrential rain that has left much of Britain flooded. For the hardy fans the conditions meant another day of frustration in traffic followed by long walks through muddy campsites, fields and car parks, while for the teams it signalled a tricky challenge ahead. Alonso dedicated his first pole since the 2010 Singapore Grand Prix to fellow Spaniard Maria de Villota, the Marussia test driver who lost her right eye after crashing last Tuesday. \"First of all I want to dedicate this pole to Maria de Villota, who is going through a particularly difficult time,\" said the two-time champion. \"We are all feeling sad these days and our thoughts are with her and her family. \"Pole was a surprise, because in conditions like these, you never know what can happen.\" Looking ahead to the race, he said: \"I\'m hoping for a boring race - given that for once I\'m starting in front of everyone!\" Alonso\'s pole came after a qualifying session that lasted two-and-a-half hours, including a 90-minutes\' rain interruption that enabled Ferrari to recover after looking likely to be left behind in Q2. As Alonso assessed his chances of extending his lead in the drivers\' championship, his rivals were worrying about racing in plumes of spray behind him on a track that could turn the race into a lottery. Briton Jenson Button, the 2009 champion, failed to make it beyond Q1 and will start from 16th on the grid in his McLaren, warned that if the rain continued the conditions for the race would be treacherous. He explained: \"Because it\'s been raining so much, the ground is soaked, so when it does rain it doesn\'t soak into the ground, it sits on top. \"That\'s a big issue. The rivers are forming very quickly even if the circuit isn\'t that wet, especially coming out of Becketts onto Hangar Straight - it\'s very wet there. \"Every time you come round it does seem like the water has moved, but I don\'t think it has! I think as more cars travel across that piece of track it clears it and if there\'s no cars the river runs freely. \"For me, when they stopped it in Q2 it was 100 per cent the right decision. It was like a lake out there, it was too wet. It\'s nothing about the skill of the drivers, it\'s whether you\'re driving the car or not, and when it\'s like that you\'re not. You\'re floating.\" On a weekend when home fans were hoping to see Button and his McLaren team shine, it was left to his team-mate and fellow-Briton Lewis Hamilton to offer a shaft of optimism despite qualifying eighth. He said: \"All I know is that it\'s going to be raining. It\'s not the end of the world that we\'re eighth. I\'m not frustrated. I would like to have been a little higher up. \"All these fans are coming to try and watch a great race and that\'s what I\'m going to try and give them. \"Jenson showed in the past coming from right at the back it\'s possible, Fernando showed in the last race coming from quite far back it\'s possible, we\'ll just have to do the best job we can and see what happens. \"Anything can happen and that\'s the exciting part of it. You have to go in with your heart and your head and get on with it.\"