KEY POINTS:
So we have ourselves another wet weekend. Sorry about that. You do realise that I don't actually make the weather right? Just double checking!
So this storm is quite a big one - not neccessarily the nastiest storm we've seen but it's certainly covering a lot of New Zealand with the west coast of the country most exposed.
As always with a system like this there's the risk of thunderstorms and tornadoes - not the big American ones but ones that MetService describe as "weak" and as the media often describe as "mini".
A number of weather enthusiasts and meteorologists dislike the term "mini tornado". It's sort of like saying "baby cyclone". It's a bit of a contradiction in terms. I think using the term "weak" is okay though. There is a scale - called the Fujita scale - which measures the strength of tornados. It goes from F1 to F5 - F5 was the one in Ohklahoma in 1999 that caused 1.1 billion dollars damage (US) to the city of Ohklahoma.
Here in New Zealand most of our tornados are given the F0 rating - some do, however make higher. F0 is when the winds hit gale force suddenly and tear parts of roofs off but doesn't really cause too much 'destruction'.
Speaking of the USA things are heating up a bit there as 2 potential storms develop in the Atlantic. They could grow into hurricanes and they're heading right into the warmer waters south east of Florida. Could be something to watch next week if youre interested in hurricanes.
While we're talking international weather - over to Beijing now for the latest forecast - and conditions, according to weather.com, look as though they'll be partly cloudy (I assume that it will, in fact, be clouds of moisture and not clouds of smog.... actually it's probably both!).
By the way I tried to access direct data on the smog levels in Beijing but I was refused access "during the Olympics" by authorities. I see some news organisations are running updates and I gather some are taking their own measuring devices. Thunderstorms come back in the mix Monday and Wednesday next week, although with high humidity and temperatures around 30 degrees isolated showers are definitely likely.
Back to NZ and a quick run down of this large storm rolling through over the next few days.
TODAY: West coast of both islands will be in for heavy showers, some with thunder and hail and localised squalls which may generate "weak" tornados. (worth nothing that damage in these events is usually only limited to a few properties nationwide). Heavy snow across the Southern Alps and nearby ranges - may also be some flurries around Dunedin and Southland. Canterbury - relatively sunny. And most of New Zealand will be windy.
SATURDAY: Heavy showers easing along the west coast of NZ. Winds also easing back a bit. Still relatively calm in Canterbury.
SUNDAY: Showers move into Christchurch later in the day as a cold southerly blows through (may not even arrive until early Monday). Some computer models suggest light snow flurries in Canterbury to sea level. Even if that doesn't eventuate, it gives you an idea as to how cold the air will be! If you live in Auckland, Sunday should see more showers I'm afraid.
Because of the size of this low it's going to take several days to fully clear the nation. So at this stage Wednesday looks to be relatively settled for a number of places - maybe Thursday to. But I'm sorry, I can't be any more positive than that! Showers are currently predicted to return later next week. This is winter after all.
Philip Duncan
For the latest weather news keep up to date with The Radio Network's new Weather Watch Centre or the NZ Herald weather section.
Pictured above: From left; Kerry Ngametua, Liam Oman, Mansell Oman, all from Camberley, Hastings, stopped off to see the swollen Ngaruroro River at Chesterhope Bridge, Pakowhai, Hastings. Photo / Duncan Brown
