Met Office – Yellow warning of fog Thurs 1st Dec 2016

Met Office – Yellow warning of fog
Patches of dense freezing fog will affect parts of southwest England during Thursday morning.

Due to the patchy nature of the fog and also the low angle of the sun, driving conditions may be difficult with journeys likely to take longer than usual.
Freezing fog is likely to be most prevalent along river valleys and over lowland areas, but isolated fog patches are also possible elsewhere. Visibility will be less than 100 metres in places. The fog is expected to clear later in the morning, although a few patches may persist into the afternoon, for instance over the Somerset Levels.

Freezing fog
Freezing fog is composed of supercooled water droplets – which remain liquid even though the temperature is below freezing-point. One of the characteristics of freezing fog is that rime – composed of feathery ice crystals – is deposited on the windward side of vertical surfaces such as lamp posts, fence posts, overhead wires, pylons and transmitting masts.

Issued at:
04:20 on Thu 1 Dec 2016
Valid from:
06:00 on Thu 1 Dec 2016
Valid to:
12:00 on Thu 1 Dec 2016