The threat of rain impacting the Australian Grand Prix this weekend has increased as Melbourne prepares for the season-opener.

Heavy rain has been forecast to hit Melbourne on Sunday morning as a massive storm system drifts across Tasmania and the southern island of New Zealand, with a trailing edge set to hit Melbourne.

Earlier in the week, forecasts were at a 64% chance of rain over the city, but this has now climbed into the 70% region, with race day morning expected to bore the brunt of the worst of the conditions. 

Winds are pushing the storm system north-east, meaning the rain will be arriving into Melbourne from the south-west, which roughly corresponds to the final corners of the track being the first area to be hit. 

Friday and Saturday of the weekend are currently forecast to be hot and dry, with temperatures up in the high 20 degrees region before the storm arrives on Sunday.

F1 has not had a wet Australian GP since 2010 when Jenson Button pulled off a typically supreme drive in changing conditions to nab his first victory for McLaren in just his second race for the team.

The final two segments of qualifying were also postponed to Sunday morning in 2013, after torrential downpours in Q1 left the track undrivable, with Sebastian Vettel scooping pole on the dry Sunday as Kimi Raikkonen won the race.