Waka Kotahi NZ Transport Agency is advising motorists that an amber alert has been issued for the Auckland Harbour Bridge between 7am and 11am tomorrow morning, with wind gusts expected to reach 75 to 80 km/h.

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

Another amber alert is likely on Saturday morning, with a low risk of brief red alert level gusts.

From Sunday morning, gusts of 75 to 80 km/h are still likely, especially with passing showers.

Additionally, there is a low risk of thunderstorms tomorrow morning, then a moderate risk tomorrow evening. Any thunderstorms could increase wind gusts above what is forecast, but this would need to track very close to the Bridge to raise the alert level.

Motorists are urged to drive to the conditions, look out for the electronic message boards which will indicate lane closures and reduced speeds, and stay within their lane while travelling across the bridge.

Drivers of high sided vehicles and motorcyclists are advised to avoid the Auckland Harbour Bridge and use the western ring route on State Highways 16 and 18.

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