The latest information at hand is suggesting a warm advection snow event may be on the cards for Canterbury from overnight and through Saturday, clearing in the evening. We must stress that understanding with these type of events, especially in Canterbury, is quite limited.

In fact, these type of snow events in Canterbury’s past have, many times, been left out of forecasts, possibly due to the hard to understand factors involved with their formation.

For the most part this storm system has turned out as we predicted, and farmers in inland areas have had good warning to take the various precautions. But for our most populated centre in the South Island (and some other eastern centres) any potential snow event this time around has been a tease for many (and a relief for some!).

From Friday night and through Saturday Christchurch could – and we repeat could – get another chance at snow, but just like Friday it will be hit and miss – and the data favours heavier falls inland rather than the coasts.

We are more confident of further snow in land, or above 100m, with the potential for heavy falls.

In the 2011 snow storm in August similar conditions happened – with snow showers, some heavy, lingering for a day or two after many thought it would be over.

Please do not take this as an “it will happen” statement, but there is potential there for some heavy snow developing about the city overnight and continuing through tomorrow. It really is a very difficult situation to comprehend and this is just a note to make you aware it could happen.

This event – if it does pull off – will span most of Canterbury and coastal Otago on Saturday.

And if it doesn’t happen?  Well, you can still expect another wintry day with sleet, hail and more cold winds from the south.  It’s the coastal snow that is borederline – not the very cold weather!

– By Aaron Wilkinson, WeatherWatch.co.nz