Ahead of today's second free practice session the air temperature is 18 degrees C, whilst the track temperature is 28 degrees.
If we learned one lesson from this morning's session it is that though the Red Bull Ring features just nine corners it is a track that demands the highest respect. Virtually every driver had at least one 'moment' this morning, some hairier than others. The green run-offs and kerbs might look innocent enough but cross them at your peril... Sebastian Vettel's double 360 exiting the final corner being a good example.
The other lesson learned is that seemingly the lunatics have taken over the asylum, as Ferrari and Mercedes ran special skid blocks fitted with titanium with the aim of producing showers of sparks as the cars bottomed and thereby making it all look more exciting.
That's assuming a four-time world champion spinning to complete 360s doesn't grab your attention.
What next, cloth helmets and shirtsleeves?
Talking of silliness, Jean-Eric Vergne is under investigation for using his 'free' set of tyres for longer than allowed this morning. The French rascal used his tyres for a full thirty seconds more than allowed.
Anyway, behind Rosberg it was Hamilton, Alonso, Massa, Button, Perez, Hulkenberg, Bottas, Magnussen and Verge.
While there was a very brief shower, the heavens finally opened up right at the end of the GP2 practice session. A slightly damp track, combined with strong winds and some deceptive corners could lead to fun and games this afternoon.
For the third successive race weekend the tyres on offer are soft and supersoft, the options making their appearance over the course of the next ninety minutes.
The lights go green and Ericsson leads the way, followed by Chilton. The Swede missed much of this morning's running with a technical issue. Sutil, who also lost a lot of running time, is another early riser, as are Button and Kobayashi.
In fact, with some very dark clouds in the distance we expect it to get quite busy in the next few minutes.
As more and more drivers pour on to the track, Sutil goes quickest (13.627), ahead of Kobayashi and Chilton.
An 11.914 sees Button go quickest only to be eclipsed by Kvyat's 11.749. Elsewhere, Magnussen is battling with a Lotus as though it's Sunday afternoon.
Raikkonen stops the clock at 11.722 only for Button to improve again, the McLaren driver crossing the line at 11.403.
Sutil locks up at T1 as Ericsson does the same at T2, elsewhere Alonso is told of a strong tailwind at T8.
As Rosberg begins his first flying lap, Alonso goes quickest overall with an 11.217. Moments later the German posts 11.279 to go second. Elsewhere, Hamilton runs wide in T8.
Rosberg improves with a 10.835 as teammate Hamilton posts 1.841 to make it a Mercedes 1-2. Again.
Next time around Hamilton ups the ante with a 10.525, we dread to think what the pole time might be.
Mind you, opposition isn't exactly hanging around, Bottas, Alonso and Massa are all within 0.5s off the Mercedes duo. As in Canada the Williams duo is looking mighty strong. Indeed, Bottas splits the Silver Arrows with a 10.790.
Twenty-odd minutes into the session everyone has posted a time.
Despite being the pace-setter, Hamilton is advised that he's losing time in T2. Rosberg closes to within 0.039s of his teammate.