With the first F1 practice session having already been affected by intermittent showers, and with dark, brooding clouds encircling Hockenheim and closing in rapidly, it was no wonder that the cars lined up on pit lane ahead of the start of the Friday GP2 practice session in an effort to get some running in before the anticipated downpour arrived.
Esteban Gutiérrez led the cars out and was best placed to set the fastest lap, but in fact it was Marcus Ericsson who went top with a lap of 1:25.568s just 0.059s ahead of the Lotus GP's first serious effort, with Max Chilton only a hundredth of a second further back.
James Calado then restored the Lotus honours with a flier of 1:25.092s soon after to go almost half a second clear of the rest of the field, on a weekend which will see both him and his team mate have to serve a ten-place starting grid penalty for incidents during the Silverstone sprint race a fortnight ago.
Cars were already struggling to find grip and not slide off the track - Johnny Cecotto Jr. taking an early detour off the track at turn 1 before his first flying lap endeavour, with Arden's Simon Trummer and Carlin's Rio Haryanto also off-roading as the spots of rain started to pick up. While cars were able to find faster times in the first and second sectors there was a short hiatus before times started to really pick up overall and allow the order to get shaken up, starting with Luiz Razia posting a 1:24.151s in the Arden.
DAMS' Davide Valsecchi then went top with a lap of 1:24.031s, 0.120s ahead of his chief rival for the championship, with Esteban Gutiérrez also improving his times to climb back into third ahead of Coloni's Stefano Coletti, Caterham's Giedo van der Garde and Racing Engineering's Fabio Leimer. Calado himself also managed improved his time by over half a second from his early benchmark, but it only enough to hold seventh place at the midpoint of the 30-minute practice session.
Proceedings came to an abrupt halt at this point after Giancarlo Serenelli ran wide in the Venezuela GP Lazarus through turn 12, went onto the damp astroturf and lost traction, spinning across the track and into the trailing edge of a tyre wall on the other side. The impact did extensive damage to the front left of the car and left Serenelli looking somewhat unsteady on his feet once he climbed out of the cockpit, but otherwise unhurt as he walked to the medical car.
A red flag for the clean-up was required, during which time the clock carried on counting down while the rain returned and picked up to make it a genuinely wet track, making improvements in lap times for the six minutes remaining in the session unlikely.
The weather did allow some drivers like Fabio Leimer to run the odd lap on slicks to test out how well they performed in such conditions, while others opted for a trial of the wet weather tyres. Esteban Gutiérrez decided not to try either approach and instead stayed dry in pit lane, where he soon found himself joined by an increasing number of drivers who were concluding that the situation was now in too much of a "no man's land" for useful running.
Tom Dillmann managed claim 13th place on the timesheets on his return to Rapax, well in front of his team mate Ricardo Teixeira who footed the timings over four seconds off Valsecchi's time. Sergio Canamasas put in a creditable lap of 1:26.475s to go 23rd on his début track outing in GP2.
With more rain forecast in the afternoon, qualifying at 2.55pm could prove to be more of the same, and as much a factor of being able to time when to be out on track for their flying laps in changeable conditions as it is a matter of raw speed or driving ability.
Full practice session times