The heavy rain on November 11 caused slips and flooding in Northland, including this slip on Russell Rd in Helena Bay.
Flooding, slips and road closures have marked the wettest November in Northland on record.
A total of 365mm of rain – more than five times the usual level – was recorded in Whangārei for the month, a “huge amount” when compared with the 71mm average in the city for November, said MetService meteorologist John Law.
It is the most amount of rain recorded in Whangārei in November since records began in 1943, well and truly beating the previous record of 257.6mm in 2000.
“So it’s not only a record but a substantially large amount of rainfall,” Law said on Wednesday afternoon, as rain continued to fall in Whangārei.
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More than a month’s worth of rain fell from the skies on two days: Tuesday, November 8, when 98.2mm fell and Friday, November 11, when 117mm fell.
There was flooding and slips on both days, with State Highway 1 having to close overnight on November 11 due to flooding at Whakapara.
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Whangārei District Council estimated the clean-up from November 11 would cost millions of dollars.
Law said the wet weather was caused by moist, warm air coming in from the northeast, bringing subtropical moisture to Northland.
In the short-term, the weather forecast for Northland was for finer weather, with a high pressure system coming in from the Tasman Sea over the weekend, he said.
But Niwa’s seasonal climate outlook is predicting summer temperatures in Northland to be above average and for rainfall to be normal or above normal.