Wellington Flash Floods and Auckland Gales Batter New Zealand

Wellington Flash Floods and Auckland Gales Batter New Zealand

MetService meteorologist Paris Marshall said multiple reports and observations of hail and intense rainfall were logged across the capital as the storm moved east toward Lower Hutt. A severe thunderstorm warning was issued for Wellington during the morning, including for torrential rain, before later being lifted. Fire and Emergency NZ stated it had no weather-related callouts from the downpours.

Wastewater Discharge and Swimming Warnings Issued

Responding to commentary on social media, Wellington’s deputy mayor Ben McNulty stated that three-water provider Tiaki Wai should investigate what went wrong, noting the area had not flooded significantly during heavy rain events earlier in the year.

Tiaki Wai issued an alert stating that heavy rain led to a discharge of fully treated wastewater into the Waiwhetū Stream in Lower Hutt, which empties into Wellington Harbour. The provider warned that the discharge could appear cloudy, murky, or have an odour, advising recreational water users to follow Land Air Water Aotearoa (LAWA) advice and stay out of the stream for the next two to three days. LAWA marked all swimming spots on the north and east of Wellington Harbour as well as Oriental Bay as unsuitable for swimming.

Auckland Strong Wind Watch and Harbour Bridge Restrictions

North Auckland and Auckland were also expected to face severe weather, with a Strong Wind Watch in place for Auckland and Great Barrier Island until 7pm on Saturday. MetService meteorologist Paris Marshall warned that exposed places could experience potential gusts of 100kph, which is enough to flip a trampoline or take down power poles.

The New Zealand Transport Agency Waka Kotahi (NZTA) warned that strong, sudden winds could close the Auckland Harbour Bridge intermittently, with wind gusts expected to reach 90-100 km/h. NZTA noted that speed restrictions and lane reductions were likely, while temporary full closures might be required if severe winds gusted over 90km/h.

Central North Island Slips and Road Closures

Heavy rainfall overnight, combined with a 5.9 magnitude earthquake near Taumarunui, caused several road slips and closures across the central North Island. State Highway 3 (SH3) through Awakino Gorge between Mokau and Piopio was closed due to a slip. State Highway 43 was also closed between Whangamōmona and Taumarunui, though it remained open between Stratford and Whangamōmona.

MetService recorded 48mm of rain in the past 24 hours in Taumarunui, while nearby National Park saw 73mm over 24 hours. NZTA advised motorists to avoid the affected areas and delay travel while geotech crews assessed the road slip sites. Additionally, MetService issued multiple road snowfall warnings across the country, including for Desert Road (SH1), Lewis Pass (SH7), and Porters Pass (SH73).