Weather warning: Auckland Harbour Bridge speed reduced, closures possible as thunderstorms roll in

MetService is warning Auckland may be hit by hail, thunderstorms, and the chance of a small tornado as Waka Kotahi reduces the speed on the Harbour Bridge, with closures possible today.

There is a low risk for severe thunderstorms in both Auckland and Northland, which may produce brief heavy rain, small hail, wind gusts of 90 to 110km/h and a small tornado.

The showers and heavy winds will be consistent throughout the weekend as an unstable southwest flow affects the west coast of New Zealand.

Waka Kotahi has issued an amber alert for this morning between 7am and 11am with wind gusts expected to reach 75 to 80km/h on the bridge.

Under an amber alert, speeds are reduced and some lanes on the bridge may close.

SH1 AKL HBR BRIDGE - STRONG WINDS
Due to predicted strong wind gusts AKL Harbour Bridge will be operating with 4 lanes in each direction during this morning's peak travel period. Expect delays. Take extra care especially if you are in a lighter or high-sided vehicle. ^MS pic.twitter.com/lCizY49rzv

— Waka Kotahi NZTA Auckland & Northland (@WakaKotahiAkNth) June 29, 2023

This may happen again on Saturday morning, with severe gales of the same speeds reappearing briefly, authorities forecast.

Passing showers will accompany the strong winds on Sunday morning, which may bring about a thirdber alert.

Our latest Severe Weather Outlook is out. In addition, a Heavy Snow Watch has been issued for southern areas from 3pm Sat to 9pm Sun. Road Snow Warnings are out for the Milford and Crown Range roads tonight. Get the latest at https://t.co/qHyE5zzql5 pic.twitter.com/d9oDx1juPc

— MetService (@MetService) June 28, 2023

MetService meteorologist Alain Baillie forecast temperatures across the weekend for Auckland are about average for this time of year, but this could be deceptive.

“The strong wind and frequent showers will mean the 15 degrees forecast for Auckland will feel more like 8 or 9 degrees,” Ballie said.

Waka Kotahi also warned of thunderstorms this morning and evening, which could increase the speeds of the winds.

“This would need to track very close to the Bridge to raise the alert level,” Waka Kotahi said in a statement.