I am sure it is not unknown – Cold snap brings snow to Sth Canterbury.
Perspective from the NZ Herald in Auckland, I saw earlier about a bridge out on the West Coast – it has been known to rain there. Does anybody have an online source showing if the rain event was unusual for this time of year ?
Wow! Snow in Timaru in summer on the east coast of the South Island. Was there in Feb last year and it was nice a warm. The west coast of South Island gets lots of rain all the year round. On the west coast of Tasmania (Strahan, Queenstown) they say it rains 2 out of every three days. It rained when we reached Milford Sound (south west coast NZ about the same latitude 44-45 south as Strahan) last Feb. Temperature was about 15C in the rain.
I was at Mt Cook Xmas in the early 80s (probably about 1981) when it had 600mm rain in a day. That is real rain with lakes forming on any ground that was near flat. The Tasman was bank to bank and up at the top of Pukaki, it is a very wide river. I remember going down to watch the Hydo dams spill. Benmore has a really spectacular ski ramp to reduce the water’s energy.
Whenever there is a big NW wind, it is heavy rain in the Southern Alps which sometimes spills over into the Canterbury foothills. You are then in the situation of the Canterbury rivers in flood, but it hot and sunny on the plains.
It is the southerly that brings snow to the mountains. These often follow the NW winds. They can come on very quick so you can get a 20°C temperature drop in a few hours.
This animation shows how localised the heavy rain can be an snow for January
www.metservice.com/maps-radar/rain-forecast/rain-forecast-3-day