This week is certainly going to be a week of two halves, the first half anticyclonic and then the second a mixture of fronts and depressions.
Yesterday spring started nicely with settled sunny conditions for most, the result of an anticyclone centred over the South Island. We had some cloud and the odd shower move into the east coast of the North Island and areas north of Auckland due to the air flow around the high however. Today is looking to be a repeat of yesterday although areas north of the Waikato could see a late afternoon shower or two then clearing in the evening.
On Tuesday something interesting happens. The dominant high pressure system giving mainly settled weather slinks back west across the Tasman Sea with it’s centre shifting to just off the coast of southeast Australia. The weather over the country for Tuesday remains largely settled once again however the high pressure system starts to move deep into the south Tasman Sea later on Tuesday and this forces cold air out of the southern ocean and sets us up for Wednesday when things become fairly colder.
Midnight Tuesday a cold front hits the lower South Island working it’s way up the country reaching Auckland early afternoon on Wednesday, so this front is moving at a reasonable pace. Rain or showers is likely to accompany the front with the highest areas of precipitation likely to be in the east of both islands, some small hail is also possible for many regions due to the cold air.
Snow will be on the minds of many, particularly farmers. At its lowest points, snow is looking to lower to 200m on Wednesday morning about the south of the South Island and to 300m about Canterbury by Wednesday evening. The snow level about the Wellington area even get’s down to about 400m in the evening so this could affect the Rumataka hill road.
Ski fields all over the country should benefit from this cold change and it will be very welcome boost for the last month or so ski fields will be open.
Snow should only be brief.
Cold showery conditions gradually clear up from the country on Thursday however New Zealand isn’t left alone for long as another front moves onto the South Island on Friday, this time the air associated with it doesn’t look to be as cold.
Homepage image / Jenette Smith
By Weather Analysts Aaron Wilkinson and Philip Duncan – WeatherWatch.co.nz