Auckland on track to beat record for most rain days in a calendar month

Monday, 26 August 2019

Auckland is knocking on the door of a rain record despite levels being normal for the month of August.

According to National Institute of Water and Atmospheric Research (NIWA), the city is on the cusp of breaking its record for the most rain days in a month, set just last month when July clocked up a total of 28 days.

With five days left in August, rain needs to fall on four of those to take the crown.

Auckland is on track to break a weather record which was set just last month.

'Today takes us to 25 days. It looks like there's low chance of rain on Tuesday, and Saturday. Most likely dry. The other days have a good chance of rain,' NIWA meteorologist Ben Noll said.

* 'Severe' thunderstorm warning, possible tornadoes for upper North Island**

'It's going to be a down to the wire finish. We're going to need a couple of bounces to go our way.'

Noll was careful to point out the record wasn't for consecutive days of rain which had previously been reported.

There had already been a day this month - August 19 - where the city didn't receive any rain, he said.

So if Auckland wasn't receiving more rain than normal for this time of year, why are rain days so consistent?

Noll said it had been an 'active month' in terms of weather with lots of low pressure pushing in from the 'moist' Tasman Sea.

'To strengthen those systems we've had a very active jet stream well above our heads which has helped energise or invigorate those systems,' Noll said.

'We've flicked a bit of a switch. We've turned up the energy dial on the systems that have come from the west.'

Prior to last month, the previous record was set in August 2010 when 27 rain days were recorded.

Rain is collected at Auckland Airport and at least 0.1 mm needs to be collected for the day to constitute a 'rain day'.