Australian MotoGP star Jack Miller is hoping for the best but fearing the worst with forecast wet and wild conditions set to make life difficult for riders this weekend at Phillip Island.

Heavy rain and high winds are set to lash the grand prix circuit on Friday, but Miller is hoping conditions ease for Saturday's qualifying sessions and Sunday's race.

"It looks like it's going to be tricky conditions ... typical Phillip Island - wet, cold and windy," Miller said.

"It isn't really the best conditions for us ... just the wet weather is hard enough but then, if you throw in the cold and the wind around here, it doesn't sound like much fun.

"Hopefully the weather gods shine down on us and give us some decent weather ... not only for us but the fans too."

Miller broke through for his maiden MotoGP on his Marc VDS Honda at the Dutch grand prix in June, but he will be happy just to crack the top 10 on Sunday.

"A lot of people might be expecting a little bit too much," he said.

"They hear you've won (a race) and they think you're going to come here and hope for the victory, which isn't the position we're in at the moment."

Miller has battled back, hand and arm injuries in a torrid second season in the top flight MotoGP class but he is feeling good after returning from his latest injury layoff at the Japanese grand prix on Sunday.

Spanish star Marc Marquez wrapped up this year's world championship - his third - with a win at the Twin Ring Motegi circuit, which will allow him to enjoy the final three races of the season.

"The feeling is amazing ... I'm much more relaxed," Marquez said.

"I didn't expect to win the title (in Japan) with three races left but now we will enjoy the last part of the championship.

"This is one of my favourite circuits, I enjoy it a lot, last year it was an amazing race."

The Repsol Honda star took the chequered flag at Phillip Island last year after a thrilling final lap dogfight with Valentino Rossi, Andrea Iannone and Jorge Lorenzo.