The official meteorological start to spring is exactly a week away (Tuesday September 1st) and on that date reliable long range data is showing the chance of a small but sub-tropical low dropping down over northern New Zealand.

Sub-tropical lows don’t automatically create severe weather – but they can rapidly deepen and bring areas of very heavy rain and localised gusts.

With the low expected to deepen as it crosses over New Zealand on Tuesday and Wednesday next week it’s one to watch, but remains at the lower end of the risks scale.

While borderline, if the low drops far enough south and deepens east of Hawkes Bay next Wednesday it may also bring in some rain to dry parts of North Canterbury, perhaps Thursday – although south of Christchurch may not receive a drop from this low, which indicates how borderline it is there.

This sub-tropical low will be followed by a Tasman Sea low just a few days later next weekend (Sept 5 and 6)

Neither lows look too serious but the sub-tropical elements means those with concerns should be up to date with the latest long range maps to track where any intense pockets of weather might be…and of course we’ll up date you closer to the time.

The two lows means spring will kick off mild for many areas, athough by next weekend the Tasman Sea low may bring in a brief cool southerly for the South Island.

– Image / File, Keith Morgan
– WeatherWatch.co.nz