Hawke's Bay Airport flights back to normal as fog clears

Fog over Te Awa on Thursday. Photo / Duncan Brown

Flights into and out of Hawke's Bay Airport were back to normal yesterday after heavy fog forced the abandonment of 16 flights.

Several flights into the Napier-based airport had to be abandoned with some aircraft unable to land in thick fog, while flights out of the airport had to be cancelled before take-off.

An Air NZ spokeswoman confirmed a total of 13 flights in Napier were "impacted" by fog over both Wednesday and Thursday.

All flights were running as normal yesterday .

Jetstar flights were also back on track from yesterday morning.

"We cancelled three flights altogether - one from Napier to Auckland and one Napier to Auckland return - that was due to fog.

"Most people were put on to the services yesterday."

Jetstar also yesterday put on an additional service from Napier to Auckland at 9am.

MetService meteorologist Tom Adams said there were two kinds of fog that formed in New Zealand.

"There's radiation fog and advection fog. Radiation fog forms in-situ, basically the air cools down enough in one spot that the air condenses and water droplets turn into fog, and that can't happen when it's windy.

"The other sort is advection fog which moves in from somewhere else, and that's what happened in Napier. When it happened, the wind was a medium north-easterly about 6 or 7 knots. So, that air was coming in off the harbour. There would have been sea fog out at the harbour and that was advected to the airport.

"The fog came to Napier Airport in the evening. It arrived about 5pm. It cleared up again at about 7pm but then came back at night - so it was probably a bit of a combination at that point. The mist had rolled in off the ocean but it was also cooling in-situ because the winds had cooled and dropped.

"The fog persisted from about midnight to about 4.30am."

Adams said a southerly change was expected overnight, and that would remove any real chance of more fog today. However, there would be a chance of showers during the day, before things fine up later in the evening.

"It's not bad on Sunday, particularly in the afternoon, we should see some fine spells."