Speed limits have been significantly reduced on Auckland's Harbour Bridge amid a strong wind watch and warnings that all lanes could close with short notice today.
A speed limit of 50km/h is currently active on the bridge. From 12pm to 9pm a red alert is in place, indicating all lanes of the bridge could close should high gusts hit.
Gusts of 90 to 100km/h are forecast, as well as possible gusts of 100 to 110km/h.
Several lanes were closed between 11am and 12.25pm due to severe wind.
The agency has asked motorists to be cautious and to drive to the conditions.
Earlier, for the morning rush hour, NZTA said the road was operating with four lanes in both directions. The bridge normally changes lane configuration during morning and evening rush hour, with five lanes dedicated to the peak-direction traffic.
"Look out for the electronic message boards which will indicate lane closures and reduced speeds, or full bridge closure, and stay within their lane while travelling across the bridge," the agency said in a statement.
"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.
"Waka Kotahi is working closely with MetService to monitor wind speeds with maintenance crews out on the network ready to react and close lanes on the bridge if wind gusts exceed threshold levels."
Safety protocols require the bridge to be closed to traffic when there are sustained wind gusts of 90km/h or higher. Otherwise, temporary lane closures and speed restrictions are used during severe weather, according to Waka Kotahi.
The eight-lane bridge is part of State Highway 1 and links Auckland's North Shore with the rest of the city. Around 170,000 vehicles travel across the bridge daily.
Motorists are asked to use Waka Kotahi NZTA's traffic updates page as well as the NZTA Auckland and Northland Twitter page for any updates.
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