When it comes to the end of Winter and the start of Spring, New Zealanders have the choice of four dates and none are official.

The Ministry of Internal Affairs confirmed to us several years ago that the Government has no official preference on when the seasons change. MetService and NIWA talk about both the Astronomical and Meteorological dates to the seasons. 

However there are really four different start dates to Spring – and you can take your pick as to which one you prefer to go by as none of them are a perfect guide. 

When does Winter End and Spring Start? It all depends on what your definition of ‘winter’ is…

• Astronomical Dates (winter starts on the shortest day, around June 21, spring therefore doesn’t start until the equinox around Sept 21 (this year the date is Sept 23, it can move +/- a couple days each year). This date is based on the earth’s angle and rotation around the sun and not the weather. A number of plants don’t trigger spring growth until the equinox, as that is when daylight hours start to become longer than the hours of darkness. 

• Meteorological Dates (winter starts on June 1, spring starts Sept 1, summer starts Dec 1, etc). This is done for record keeping as a tidy date to start from and often co-incides with the seasonal changes too.

• Solar Winter (The 3 months/12 weeks of the year with the least amount of available sunlight with the shortest day of the year in the middle, meaning the Solar Winter runs from early May to early August – so the ‘solar spring’ kicked off in early August.

• Mother Nature – The reality is that New Zealand really does have a shorter 2 month summer and a shorter 2 month winter in WeatherWatch.co.nz’s view… the other 8 months are a long drawn out spring and autumn. We see the evidence of this and measure it in the form of animal life cycles, pollen, flowers, buds and grass growth, not to mention current weather patterns too.

– Image / A fishing boat coming across the bar at Greymouth. Uploaded by: Gill Bensemann Date: 18th Aug 2018.  The Greymouth bar and the entire West Coast can be incredibly rough and stormy during the transition from August to September, but this year it hasn’t been quite as rough thanks to a lack of winter storms.

– WeatherWatch.co.nz