There was a cold start to the day. Over Abbey Meadow, aircraft vapour trails criss-crossed the sky and reflected in the River Thames. Exhaust from jet engines mixed with the very cold air at high altitude. The water vapour condensed into tiny droplets which then froze into ice crystals.

The sun appeared over the south-eastern horizon at about 7:30. That was later than the 7:20 sunrise time predicted online, possibly because the published time assumes a level horizon.

The river was warmer than the cold air above it, allowing water to evaporate. The water vapour cooled and condensed into tiny droplets, creating evaporation fog.

The walk to Abingdon Lock was about half a mile out alongside Abbey Meadow, and half an hour back along the Thames Path.

There were icy puddles, and the plants were furred with frost.

St Helen’s Church caught the early sunshine on what was a fine start to the day.