Romain Grosjean set the pace at a very wet Silverstone circuit before conditions deteriorated resulting in most heading in and staying in their garages.
As the rain came down on an already very wet track, the first of the weekend's three practice sessions got off to a slow start with Kamui Kobayashi setting the early pace with a 2:02.254.
Sebastian Vettel was the first of the big names to head out but was over eight seconds down on Kobayashi while his Red Bull team-mate Mark Webber followed him out and took the P1 slot with a 2:01.153.
Daniel Ricciardo was the next to lead the way with a 1:58.581 despite having to correct himself several times through the final corner.
That kicked off the battle of the Australians as Webber and Ricciardo traded fastest lap times while others, including Jean-Eric Vergne, Romain Grosjean and Dani Clos, struggled to stay on track. Grosjean put an end to the Aussies-only tussle, taking the P1 slot with a 1:56.552.
As the rain continued so too did the errors with Grosjean, Heikki Kovalainen, Pedro de la Rosa, Timo Glock and others either running off the track or spinning on the wet asphalt.
With thirty minutes to go three drivers had yet to set times, Fernando Alonso, Paul di Resta and Jules Bianchi, however, only di Resta had a problem as his Force India team changed his steering. The other two just didn't run want to run in the dismal conditions.
As the conditions deteriorated most of the drivers opted not to head out again while those did were on average ten seconds slower than their previous best times. And although di Resta and Alonso both put in a few laps in the final 15 minutes neither set a time.
Practice One ended with Grosjean in the P1 slot with a 1:56.552, 0.275s ahead of Ricciardo and 0.622s up on Lewis Hamilton.
01 Romain Grosjean Lotus 1:56.552 13 laps
02 Daniel Ricciardo Toro Rosso 1:56.827 0.275 10 laps
03 Lewis Hamilton McLaren 1:57.174 0.622 6 laps
04 Sergio Perez Sauber 1:57.664 1.112 11 laps
05 Felipe Massa Ferrari 1:58.119 1.567 7 laps
06 Mark Webber Red Bull 1:58.463 1.911 7 laps
07 Kamui Kobayashi Sauber 1:58.483 1.931 19 laps
08 Michael Schumacher Mercedes 1:58.493 1.941 10 laps
09 Nico Rosberg Mercedes 1:58.942 2.390 8 laps
10 Jean-Eric Vergne Toro Rosso 1:59.076 2.524 12 laps
11 Sebastian Vettel Red Bull 1:59.414 2.862 11 laps
12 Vitaly Petrov Caterham 1:59.614 3.062 9 laps
13 Valtteri Bottas Williams 1:59.733 3.181 7 laps
14 Heikki Kovalainen Caterham 1:59.787 3.235 10 laps
15 Pastor Maldonado Williams 2:00.125 3.573 5 laps
16 Kimi Raikkonen Lotus 2:00.253 3.701 6 laps
17 Jenson Button McLaren 2:01.834 5.282 6 laps
18 Timo Glock Marussia 2:01.835 5.283 6 laps
19 Pedro de la Rosa HRT 2:04.341 7.789 9 laps
20 Dani Clos HRT 2:05.022 8.470 11 laps
21 Charles Pic Marussia 2:11.760 15.208 6 laps
Fernando Alonso Ferrari 4 laps
Paul di Resta Force India 3 laps
Jules Bianchi Force India 1 laps