In the north of Scotland, blustery showers have replaced earlier wet weather, and Stavanger, too, in the south-west of Norway, has experienced unsettled, mild, weather with showers of rain. The principal sources of cloud, poor visibility, rain and strong winds in middle and high latitudes are weather features called depressions, which are highly mobile low-pressure systems several hundred to a few thousand kilometres in diameter. Their general direction of movement is towards the east, but they may move in any direction. In the northern hemisphere, winds blow counter-clockwise around depressions. Much of the rain has been associated with fronts crossing the British Isles, though blustery showers have occurred south and south-east of Iceland, as can be seen on satellite images available from Dundee .
Fronts are boundaries between air currents of contrasting temperature and humidity.
A cold front has today been moving southwards across Scotland and northern England, with cool air to its north replacing warmer air to its south. It reached southern parts of the British Isles this afternoon. On the eastern flanks of the depression, fronts have brought precipitation to southern Norway. In northern Finland, north-westerly winds associated with a depression north of Norway have brought temperatures lower than yesterday's, as the weather report from our school near Vaasa indicates. In the southern hemisphere, winds blow clockwise around low-pressure systems.