Heavy rain on the way

So we have a large low pressure system moving over us today...well actually, not just today, but the next few days. WeatherWatch has dubbed it the "7 day low" as it's going to affect us for about a week.

Its size is a relatively rare sight. It takes up an area of space normally equal to what an anticyclone would cover. According to the MetService weather map for the middle of today the low will actually be made up of 6 lows...all surrounding each other and helping drive in rain and showers to the country.

It's important to remember that size doesn't always mean more aggression. Think about a rugby player...sometimes the smaller guys can cause more damage with their aggressive speed and zig-zagging. Lows can be similar...the big ones certainly have a bulldozer effect and their size is noticeable...but often they don't pull any surprises out of the hat...they just barrel across the country and do their 'thing'.

This low has plenty of rain with it, tapping in to the warm air north of the country and pulling it down over us. Heavy rain warnings, which have already been issued for several regions today, will be the main characteristic of this large depression. That and warmth. Northerly wind flow = warm. Highs around 20 in the north and 16s and 17s for the south.

Our big low will slowly cross the country over the weekend - oh and another thing to note is that we're not in for 7 days of non-stop rain - despite what some weather presenters say (by the way, that's a pet hate of mine - brushing several days with the 'rain' brush when actually there will be long dry spells in between. The lows all have fronts attached and those fronts will come and go...in between may well be sunny, dry and warm. I guess fingers crossed the rain bands are at night and the clear spells are during the day.

By Monday winds will turn cooler south west and perhaps by Tuesday they may turn colder southerly ahead of a large anticyclone. If this all goes to plan then early next week should see sunny, dry, weather for those in the north and west and inland with perhaps just a few showers in southern regions of both islands.

- Philip Duncan




Photo: Expect to need the umbrella over the next few days. Photo / Doug Sherring