'Antarctic southerly' due this week

You know when you hear the words "Antarctic southerly" we're in for a cold snap - well, that's what we've got this week. Air is being pulled up from around Antarctica and is being spread across the country and while it's not looking severe it is still going to be noticeably colder. Single digit highs, possibly as low 7 for some parts of the South Island are likely on Tuesday and Wednesday. The strong cold southerly or south westerly will spread north affecting most North Island places on Wednesday and Thursday - you'll feel the gradual decrease over the next 72 hours.

Most affected by the cold change? In the North Island it's Wellington and the east coast south of Gisborne along with Wanganui and south coastal parts of Taranaki over on the west coast.

In the South Island it's Southland, Otago and Canterbury.

For those who are starting to get their heads around some of the weather patterns in New Zealand you may now be seeing another clear one - at this time of year when you have warm weather you know it's going to be followed by something cold. Strong nor'westers over the South Island are usually caused by deep lows south of the country... when the low moves east of New Zealand the winds swing to the south west or south. That's why we see highs of 22 dropping to 7 so suddenly. It's fair to say when it's warm in Autumn or Winter there's definitely a catch.

The weather patterns have definitely changed in recent weeks. It's starting to get pretty wet underfoot - in Auckland the grass is squidegy (is that a word?!) and in Christchurch some sports fields are closed already because the ground is so wet - Christchurch is hardly known for being a wet place to live. But when you have fronts bringing half a metre to the west coast you know that some will spill over.

We've been rushing at the Weather Watch Centre to keep up with all the weather news around the country. From high temps in the east, to bitterly cold temps in the south, torrential rain and flooding in the west, thunderstorms, hail storms that look like snow storms, tornados, water spouts - and this is just the past 7 days.

I'm getting a lot of people asking me about winter and whether I think it'll be cold, wet, etc. My gut instinct is that this wetter weather pattern will continue - I see no reason why it should stop. As the air becomes colder that means it'll turn to snow at higher altitudes - which would be good news for ski fields in both islands. The wetter prediction may not be so good for others though - last winter was fairly wet and many people didn't like it much - this Autumn started off dry and summer-like but is quickly playing 'catch up' with the recent change to more wintry, wet, weather.

There is some dry news - some of the long range models show western and northern New Zealand receiving a ridge of high pressure from the Tasman Sea this weekend. So while sou'westers may continue to affect eastern New Zealand winds may die out significantly by the end of the week for those in the west and the north. We'll keep you posted on that.

Your comments

I'm keen to hear from you - are you enjoying Autumn this year? Too wet? Not stormy enough? Too stormy?! Have your say below.

And remember - for all the latest weather news, updated throughout the day, every day, please visit the Weather Watch Centre.

Philip Duncan

Pictured above: Southerly winds in Wellington