Australian ski resorts traditionally and officially open on the Queen's Birthday holiday weekend, which this year falls very early on the 6th June.
These days there are usually a few beginner runs open with manmade snow when there's little natural snow (which is quite typical) on the ground.
In 2014, there wasn't much terrain open until much later in June, but then almost all lifts were running by the first week of July. A great start! In 2013, we had to wait as long as until mid-July for most lifts to open. In 2012, a few lifts opened late in June again. The most reliable time for good snow cover and lots of terrain open is mid-July until late-August.
New Zealand skifields target planned opening dates based on typical, expected snow conditions. But the seasons are unpredictable and they may have to delay when conditions aren't suitable, i.e. not enough snow. This was notably the case last year.
North Canterbury and Nelson
Rainbow 4th July 2015 (opened mid-July in 2014)
Hanmer Springs late Jun/early July 2015 (opened mid-July in 2014)
Mt Lyford late June 2015 (opened 18th July in 2014)
Mt Hutt 12th June 2015 (opened on 13th June in 2014)
Porters 19th June 2015 (opened 6th July in 2014)
Ohau 27th June 2015 (opened mid-July in 2014)
Roundhill 27th June 2015 (opened mid-July in 2014)
Mt Dobson 4th July 205 (opened mid-July in 2014)
Treble Cone 25th June 2015 (opened mid-July in 2014)
Cardrona 13th June 2015 (opened on 20th June in 2014)
Coronet Peak 13th June 2015 (opened on 7th June in 2014)
The Remarkables 21st June 2015 (opened on 3rd July in 2014)