Mushrooming fog

A typical winter rising while it was still dark this morning. A few wisps of fog were scattered around the Grey Lynn Valley below the ridge where we stay. Shortly thereafter, the fog was dense and filled the whole valley, and also covered the Ponsonby Ridge to the east, so that the Sky Tower was invisible.Almost as quickly it all went to be followed by this mushroom cloud of fog over the western suburbs. 

The extra was taken looking to the northeast at the same time.