Many Northlanders woke to a blanket of fog shrouding their view yesterday, and while the gloom will likely return today it will not be another pea souper.

MetService meteorologist Lisa Murray said the region's recent run of warm weather had a downside - heavy fog. Ms Murray said after the warmth the surface temperature of the land starts to cool down. So at about 13C the air over the land starts to get saturated as warmer air comes off the sea.

She said the conditions were ripe for more fog this morning.