Stratus

This is a featureless layer of low-level cloud usually grey in appearance. Sometimes the cover can be as low as the ground (fog), however, the usual base will be between the ground and 1,000 feet (300 metres) and can obscure the tops of hills. They can sometimes produce drizzle or snow.

The stratus are most frequently seen in the western part of Britain where the moist
south-westerly airstreams are forced to rise over the various hill ranges. Inland, the base of the stratus will lift slightly during the day and in the summer, will completely disperse. Whereas, on the coast when there is a moist south-westerly airstream, there is no such respite.