As has been alluded to earlier by WeatherWatch.co.nz, the week ahead has certainly got a spring feel to it – and the main feature to watch will be gale northwesterly winds which could affect many regions on Tuesday and Wednesday.
Today sees a moderate westerly airflow over New Zealand, with an anticyclone centred in the north Tasman Sea. A quick-moving front moves over the upper South Island and onto the North Island during the first half of the day, however doesn’t deliver much in the way of showers. Any rainfall will be mainly restricted to western areas, while out east some cloud will shoot on through for a time.
On Tuesday, things start to get interesting, as a low pressure system southwest of the country grows and moves eastwards. As it does a northwesterly airflow builds over the South Island and lower North Island, north to northwesterly winds are likely to reach gale force about much of the South Island (particularly in the east) and the lower North Island from afternoon. Rain will fall on the West Coast as a front associated with this system moves in, and will become heavy and possibly thundery.
The upper North Island remains under a ridge of high pressure on Tuesday, so should expect a mainly sunny day although some cloud will build towards evening, especially in the west.
On Wednesday the front mentioned above moves into Central parts of the country, winds behind the front will still be northwesterly and gusty at times but should ease a little. Rain is still likely for the West Coast of the South Island, out east sunnier conditions develop behind the front, Marlborough will see rain spread from the west from morning and not clearing till later in the evening. Winds will be strong to gale force for much of the day there.
Winds about the lower North Island will be quite strong from the northwest, rising to gale about Cook Strait, and Wellington for much of the day. Eastern regions are likely to see gale force northwesterlies for a time also. Rain and showers work their way north during the day reaching Auckland around midnight.
The main front associated with this spring storm gradually moves off the North Island during Thursday, behind it sees easing winds. A southwesterly airflow develops over the South Island and there may well be a few showers about, possibly even some unstable activity in southen districts with snow predicted to 300m so something to keep an eye on.
Finally the end of the working week on Friday sees a southwesterly airflow over much of the country. Once again there could be some unstable activity about with showers, hail and possibly a thunderstorm or two. Thunderstorms look more likely about the northeast of the South Island and in the west of the North Island however this could change. Some snow could also fall to 400m in Canterbury and 500m in Marlborough.
By Weather Analyst Aaron Wilkinson – WeatherWatch.co.nz
on 9/09/2013 1:08am
I see the wind is winding up here in the Waikato already. Looks set to go through until Sunday too.
on 8/09/2013 7:06pm
Tues/wed will be windy south of taupo but our windy day will be friday in Auckland,northwesterlies in that situation,we will only get the occasional gust otherwise fresh at the best.