Ahead of today's second practice session the air temperature is 24 degrees C, whilst the track temperature is 27 degrees.

If this morning was damp, this afternoon is altogether seriously wet.

Shortly after Williams tweeted "If the rain keeps up at this rate, they'll be looking down on a lake from Turn 1", the official COTA account sent out the following warning to fans: "Lightning has been spotted in the area around COTA. Please seek shelter indoors, in vehicles or in tents."

Nico Rosberg topped the timesheets this morning, ahead of Kvyat, Ricciardo, Sainz, Hamilton and Vettel.

The slicks never made an appearance even though there was clear dry line by the end of the session. That however, has long since disappeared.

Because we are expecting further rain over the remainder of the weekend we can expect a fairly busy session this afternoon. Fingers crossed.

Having handed his car over to Raffaele Marciello this morning, Felipe Nasr is back in the Sauber this afternoon.

And as we wait the lights turning green Race Control announces that the start of the session is "delayed indefinitely" as the "marshals are unable to work due to the proximity of lightning".

Meanwhile, Mexico's Pacific coast is set to be hit by the "potentially catastrophic" Hurricane Patricia.

Conditions are unbelievable, like the end of days, as imagined by Hollywood, yet still the hardy fans sit beneath their umbrellas and in their tents waiting for some action.

While, 30 minutes into the delayed session, there is still sign of any activity, it's worth noting that in a change to its usual strategy, Lotus will have Jolyon palmer in Romain Grosjean's car for this session as opposed to FP1.

The rain has eased off but it is the threat of lightning that is causing problems.

Race Control is a hive of activity with Bernie Ecclestone joining Charlie Whiting, Herbie Blash and the rest of the team as they study the weather maps and consider what to do.

At 14:45, what would have been 'half-time', the rain has increased in intensity. The sky remains dark and angry.

At 14:55 Race Control announces that the session has been abandoned as there can be "no medical helicopter operations for the next two hours".

Check out our Friday gallery, here.