Rain holds off...but now what?

The bad weather held off for the duration of the ceremony in Auckland this morning. Photo / Greg Bowker

It's another windy, cloudy, day across northern New Zealand but as predicted by WeatherWatch.co.nz the rain has held off for most Anzac dawn services and despite a rain warning being in force for Northland much of the region remains dry.

Only Tauranga and some extreme eastern parts of Northland have seen rain this morning but nothing significant has fallen. As exclusively predicted by WeatherWatch.co.nz Auckland was mostly dry, windy and warm with a temperature of 18 degrees. A few very light showers and drizzle patches have skirted some suburbs but not enough to even wet clothes. Winds are strong though with gusts to 80km/h around Auckland Harbour.

Head weather analyst Philip Duncan says he believes a few factors are at play for the lack of rain. "Firstly I think the centre of the low was just that little bit too far off shore to really drag in the rain. It also hadn't seemed to tap in to the usual very moist air that previous lows in the same area had tapped in to. Finally the main reason I think most centres are so dry is because the air pressure still remains far too high for the big rain clouds to move in through".

Mr Duncan says high air pressure pushes cloud tops down and usually reduces the amount of heavy rain. "While it can certainly rain under a ridge of high pressure, and sometimes non-stop, the odds are usually stacked against heavy rain moving in...and especially against advancing through it. The air pressure over northern New Zealand remains high and it's quite clear on the rain radar that the heavy rain is fizzling out as it heads south towards Auckland and other regions nearby".

However forecasts produced by the Weather Watch Centre confirm rain will move in to more regions as today progresses, including Auckland.

Strong to gale force winds yesterday knocked motorists and pedestrians around over Auckland and Northland but weren't heavy enough to cause damage. "The low responsible for these winds is shifting further south quite quickly. Winds will ease in Auckland and Northland this morning but build up quite significantly in Southland, Central Otago and inland Canterbury later today".

Tonight is expected to be a windy one for many South Island areas especially in the south bringing a much warmer night tonight.

"We said at the start of the week that this low would be a tough one to call. That it was 50/50 on Anzac Day due to the ridge of high pressure".

Now Mr Duncan says our attention should turn to a large low south of New Zealand. He says we're coming in to a very unsettled week ahead. "An incredibly large low is moving in from Tasmania. To put it into perspective the centre alone is the size of the South Island, compare that with today's low where the centre is about the same size as the Central Plateau".