Pictures of devastating tornado tearing through Auckland's Viaduct Harbour

Newshub has obtained new pictures of the devastating tornado that tore through Auckland's Viaduct Harbour.

And if you thought the past couple of weeks have been exceedingly wet, you'd be right.

NIWA says August has served up a record number of rainy days already.

August has certainly felt like a wet blur for most, but at Auckland's Westhaven Marina, it also dished up something completely unexpected.

As a Fuller's ferry is refuelling, an 18-meter catamaran cartwheels over the dock. 

From another angle, all is seemingly calm - before the tornado whips through. 

"The wind speed they've estimated at 200 knots which is around 400km/h, so it was savage to say the least," boat owner Andrew Stewart told Newshub. 

It left Stewart's pride and joy a write-off. 

"Disbelief really," he said. "We've already seen some pretty powerful weather and winds in our time, but that was on a different scale."  

Also in the path of the tornado was the 44-metre superyacht Encore. The top of its mast almost laid parallel to the water before righting itself. 

The tornado tore through last Monday night, leaving millions of dollars of damage along Auckland's waterfront. 

And in Awakino, a tornado destroyed three homes on Saturday - the second in a week for Taranaki.

"Those tornadoes have been encouraged by violent winds that are rotating through the atmosphere," NIWA forecaster Ben Noll said. "Not just at the ground but well above our heads." 

Noll said there are some big "dirty" lows in the Tasman that could mean more are on the way.

"It leads to unstable air and thunderstorms across the country, and that means more tornadoes? 

"Potentially we see the conditions become right for thunderstorms later this week."

Water shortage continues

Despite the seemingly constant deluge, Aucklanders still have a water shortage problem. 

The dams in the Hunua ranges - the largest catchment area for the super city, are down significantly.

They're normally overflowing in August, but are running 30 per cent lower than last year. That's due to the record dry summer and autumn, and a couple of wet weeks hasn't come close to topping them up. 

Watercare is still urging residents to conserve water, but they say it's a hard sell.