Thunderstorms, heavy rain, and high winds come with warning locals in the region to prepare for possible flooding, wind damage and tornados in isolated areas.
Metservice has forecast an unstable airmass with embedded troughs to hit the upper North Island this evening, overnight and into Saturday morning.
Thunderstorms are likely and there is a risk of downpours with rainfall intensities of 25 to 35mm per hour.
This will be in much of Northland, Auckland, Coromandel, the north of Waikato and the far west of the Bay of Plenty.
There is also a risk of tornadoes with strong wind gusts.
Wind gusts of this strength can cause some structural damage, including trees and power lines, and may make driving hazardous.
If any tornadoes occur, they will only affect localised areas.
Rainfall of this intensity can cause surface and/or flash flooding, especially about low-lying areas such as streams, rivers or narrow valleys, and may also lead to slips.
Driving conditions will also be hazardous with surface flooding and poor visibility in heavy rain.
The Civil Defence Bay of Plenty Emergency Management Group has outlined a list of things to do before, during and after a severe storm.
What to do when the storm happens
• Secure, or move indoors, all items that could get blown about and cause harm in strong winds.
• Surface flooding, restricted visability and slips are possible during severe weather. Avoid driving unless absolutely necessary.
• Power cuts are possible. Unplug small appliances which may be affected by electrical power surges.
• If power is lost, unplug major appliances to reduce the power surge and possible damage when power is restored.
• Bring pets inside. Move stock to shelter. If you have to evacuate, take your pets with you.
• Close windows, external and internal doors.
• Pull curtains and drapes over unprotected glass areas to prevent injury from shattered or flying glass.