Mild sub-tropical winds for some parts of NZ today will give way to a much colder southerly from Antarctica later this week.

WeatherWatch.co.nz says temperatures are about to tumble with daytime maximum temperatures on Friday and Saturday in the lower South Island hovering around +5 to +7 degrees.

"Snow flurries are expected down to a few hundred, or couple hundred, metres for a time - although accumulation looks low (and we'll drill down deeper on this in other updates this week)," says a spokesperson for the weather organisation.

"Generally speaking a cold southerly will impact TAS, VIC, ACT and NSW this week, but will be much more significant in the NZ area with all of New Zealand under the colder (short lived) southerly by Saturday."

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