UK Outlook - 21st March 2013 - Coldest March Weekend in 50 Years!
Leon Brown, Chief Meteorologist
Central and NW Britain is at risk of some heavy snowfalls Friday to Saturday. (Leon Brown/uk.weather.com)
Heavy snow on the way
Atlantic fronts trying to push NE against the colder easterly block to the north and east of the UK will result in some severe weather in the next 48hrs. Heavy snowfalls for central and NW Britain and the snow spreading to the south by Saturday. This weekend will be one of the coldest in many years with temperatures struggling to lift above zero and a significant windchill.
Overnight and through Friday morning rain will edge north and turn to moderate or heavy snow across Wales, Midlands to NW England and the NE of Ireland. Over the SW it will become less cold behind a warm front, but heavy showers threaten the SW later. A flooding risk over the SW of England.
By mid morning on Friday we may see 10 to 20cm over higher ground in NE Ireland and mid to North Wales, while parts of the Midlands may see 3 to 7cm, especially on the grass.
On Friday afternoon the snow will continue northwards to southern Scotland and there will be more heavy snowfalls over NE Ireland, especially above 150m. Over the Midlands the snow should turn to sleet or rain, and some heavy downpours with hail and thunder may spread to Devon and Cornwall. Temperatures 10C in the SW behind the warm front but 1 to 3C over the North Midlands to northern Britain.
On Friday night to Saturday morning the snow will begin to spread back south and westwards. By Saturday morning snow is likely in a wide band across Britain with moderate or even heavy snow in central areas. The SW though less cold and misty, but mainly dry.
By mid morning on Saturday we could see as much as 20 to 40cm over the higher parts of the Pennines, Welsh Mountains and high ground in NE Ireland. However, even over the Midlands to SE England 3 to 8cm is possible with 10-15cm over the central to North Midlands.
On Saturday afternoon the snow across central Britain will gradually become lighter and more showery in nature, and spread a little further to the west. Still bitterly cold in fresh and gusty easterly winds with temperatures near zero across much of central and northern Britain and only a couple of degrees above in the far south. The exception the west of Cornwall where 7 to 8C is more likely.
Sunday will stay bitterly cold again in the easterly winds. A few light snow showers in the east at times and perhaps some more widespread snow showers in the far SE. Brighter in the west. Temperatures still not far from zero in the south and only 2 to 4C in the brighter areas, some 8 to 10C below normal.
Not much changes for Monday either with isolated and light wintry showers in the east which may give a fresh dusting of snow, but generally dry weather and very cold in moderate to fresh easterly winds. Temperatures not much above 3 or 4C in most places.
Extended Outlook
As pressure builds and winds become lighter daytime temperatures will manage to lift a bit, but still well below normal. Mainly dry for the end of the week with more sunshine. However, there will be some very cold nights, especially Wednesday and Thursday morning with temperatures below minus 10C in eastern Scotland and Grampians area, but perhaps minus 8C in the south too.