WeatherWatch.co.nz is again advising residents and farmers in the upper North Island to prepare for possible slips and flooding as yet another big rain maker organises itself out in the Tasman Sea.

The low is likely to peak around Wednesday with rain clouds growing significantly over the upper North Island later in the day.

“Again we’re going to see a rain band intensify out to the east after it passes Auckland on Wednesday evening.  This rain band could become quite explosive in some areas producing very heavy rainfall rates and further thunderstorms” says head weather analyst Philip Duncan.

Mr Duncan says the rain will set in across Bay of Plenty and should last well into Thursday.

Image / Rain prediction for 6am Thursday shows light to moderate rain (purple) lingering in Auckland and Waikato but heavier rain over Bay of Plenty (pale blue and yellow) – in particular eastern Bay of Plenty / Weathermap

Various models and data point to the heaviest rain falling in Bay of Plenty where flooding is most likely.  In particular eastern and inland parts of Bay of Plenty, also the western slopes of the Gisborne and Hawkes Bay ranges.

While heavy rain is predicted in Auckland and Waikato for a time it appears, at this early stage, that the biggest downpours will be east of the Kaimai and Coromandel ranges.

Great Barrier Island, Coromandel Peninsula and East Cape may also be in the firing line for heavy rain and thunderstorms.

By Friday another low in the southern Tasman Sea or Southern Ocean will fire heavy rain into the West Coast and gales along southern and eastern parts of the South Island – and possibly into Cook Strait too.

Friday and Saturday’s low will mark an end to the persistent northerlies over the past three weeks.

– WeatherWatch.co.nz