We all know that with the arrival of winter, we expect the weather to get colder, but is that all winter brings?
Met Office Meteorologist and Weather Presenter Aidan McGivern gives his best winter weather facts.
March is snowier than December
Dreaming of a white Christmas? You might need to keep dreaming. On average across the UK there are just 3.9 days of snowfall in December. However, this average number masks huge year-to-year and regional variation. Typically, we can expect more than two weeks of snow in December for some Scottish summits versus one day or fewer for the Cornish coast.
December is the darkest month of the year – the midwinter solstice occurs just before Christmas – but there is a significant lag in the cooling of the land and surrounding seas. January is, on average, Britain’s coldest month. February is the snowiest month of the year. Even March – the official start of spring – is snowier than December with a UK average of 4.2 snow days. Indeed, there is a greater chance of a white Easter, if it occurs in March, than a white Christmas. Find out more about Met Office weather records and averages https://www.metoffice.gov.uk/public/weather/climate
The Earth is Closest to the Sun During the Northern Hemisphere in Winter
Despite what you may think, the Earth isn’t a perfect sphere. Instead, we live on a lumpy oblate spheroid – a planet that bulges at the equator as a consequence of its spin. The Earth’s orbit around the sun isn’t straightforward either. Rather than a circle, it’s an ellipse – an approximate oval shape. The elliptical orbit itself isn’t perfect; the sun isn’t even in the middle of it. The gravitational push and pull of the sun, Earth, moon and other planets help to slightly deform the Earth’s orbit, which causes variation throughout the year in the distance of our nearest star.
Around the 3rd January, the Earth is closest to the sun – by more than 3 million miles to the 5th July. Given that the average distance from Earth to the sun is around 93 million miles, that’s not an insignificant distance. Nevertheless, the tilt of the Northern Hemisphere away from the sun during winter and towards the sun in summer has a much bigger impact on the seasons.
Wet Snow is Better for Making Snowmen
Whilst winter sports enthusiasts often view dry, powdery snow as the best for skiing and snowboarding, wet snow is better for the simpler pleasure of building a snowman. The difference is in the amount of water content in the falling snowflakes. Wet snow normally occurs in air around or just above freezing. The snowflakes melt slightly, becoming bigger and heavier and the extra water content helps the snow to stick together. Dry snow normally occurs in much colder air in which there has been very little melting. These smaller snowflakes will contain less water. Try to fashion a snowball from powder snow and it will crumble in your hands. Read more information from the Met Office about snow https://www.metoffice.gov.uk/learning/precipitation/snow
The UK’s Lowest Temperature has been Recorded Three Times
Braemar, Aberdeenshire on 11 February 1895. Braemar again on 10 January 1982. Altnaharra, Highland Scotland on 30 December 1995. Three separate occasions, two different locations; all share the title as the UK’s coldest time and place. Precisely -27.2 °C has been reached three times since UK records began, but never exceeded. You can find out more about climate records and extremes here https://www.metoffice.gov.uk/public/weather/climate-extremes/#?tab=climateExtremes
Cold Weather Increases the Risk of Heart Attacks
This risk is greater for the over-65s and for those who have health conditions. The cold thickens blood and increases blood pressure. Breathing in cold air can also increase the risk of chest infections.
Your home (and those of your elderly relatives and neighbours) should ideally be heated to at least 18 °C. During cold spells the advice is to keep windows closed at night as this could cause a significant drop in the temperature indoors.
If you have a heating boiler consider getting it serviced before the coldest weather arrives. Find out more about heating your home and ways you can save money.