In the past hour the free and live Lightning Tracker has shown a jump in activity north of Auckland.

The showers – which will be heavy and squally at times – have the potential to cause isolated pockets of damage tonight.

While showers have become less frequent this afternoon – and winds have eased a fair bit too – conditions are predicted to change this evening.

Showers will become heavy and frequent from Taranaki northwards – with the bulk of the heavy showers affecting Northland.

However these heavy showers should also clip Auckland and surrounding regions.

Showers may bring short bursts of torrential rain and cause localised surface and flash flooding. Motorists are advised to drive with care overnight tonight.

Some showers may include thunderstorms and squalls are likely – which could suddenly, and without warning, bring damaging gales to localised areas.

Not all parts of each region will be affected by severe weather – but the potential is there.

There is also a risk of small tornadoes, either EF0 or EF1 rating (the lowest on the scale). These are possible across Northland and potentially Auckland, Waikato and BOP and, should one occur, be similar to other small tornadoes reported across NZ this year.

Should a tornado hit your home, immediately get into a small windowless room, or hallway. Do not close windows and do not go outside. They pass quickly and conditions should ease within minutes.

Overall winds will be westerly and may be gale force at times, but not likely to be damaging. During Tuesday winds will turn south west and potentially strengthen further – this may be close enough for a wind warning to be issued by the government forecaster.

– WeatherWatch.co.nz