The very cold winter of 2009-10

Winter 2009-10 was the coldest since 1978-79 measured by Central England Temperature (CET) and the second consecutive cold winter. It brought widespread and disruptive snowfall.

December

This was the most memorable month of the winter in the Chiltern region, with exceptionally heavy snowfalls in the run up to Christmas.

5th December 2009

Way to the north of the UK, cold air was beginning to funnel out of the Arctic, instead of its usual position to the west of Greenland. Medium-range computer forecasting models also began to show cold weather developing across western Europe by the middle of the month.

12th December - cold air starts to arrive

Cold air was flooding across Europe, and with high pressure to the north, it seemed highly likely to make its way to Britain, which it indeed did.

17th December - heavy snow

I'll remember this day for a long time! Very cold weather was established across the country, but the day started dry and sunny in the southeast. Light snow showers developed through the morning and afternoon, giving a thin covering of snow in the Chilterns, just north of London.

Pressure and 850hPa temperatures, 17th December 2009
Pressure and 850hPa temperatures, 17th December 2009

By the evening, prolonged spells of snow developed and continued for much of the night, resulting in a snow depth of over 20cm and drifts of close to 2m in fields. The next day was bright and bitterly cold, with the powdery snow making for excellent skiing conditions in the hills! 

Snow and sunshine in the Chilterns
Deep snow and bright blue sky, 22nd December 2009

22nd December - more heavy snow

The snow was still lying deep with the cold weather persisting. The day began overcast with the prospect of rain, sleet, or snow later on. What followed during the afternoon and evening was another 15cm of snow. The snow was wet, sticking to the trees and power lines as it fell. During the night, it cleared away, allowing the temperature to fall well below freezing. A sunny and very cold morning followed, making for postcard scenes in the Chilterns!

Heavy snow blanketing the Chilterns
Heavy snow snow blanketing the Chilterns, 22 December 2009

Christmas day

Temperatures had risen slightly by Christmas day but there was still full snow cover. This meant that technically it wasn’t a white Christmas as no snow fell on the day itself.

January

By the New Year the cold was beginning to intensify once again, with snow showers returning. The first week of January brought bitterly cold weather, and the third heavy snowfall of the winter, with another 15cm accumulation.

The second week began with another 8cm of snow, but less cold conditions then brought a thaw, and rain returned. The cold didn’t really return during the rest of the month, but despite this, the month was very cold overall.

During January, I spent 2 weeks in Courchevel in the French Alps. The conditions there were the coldest I have experienced. Even in the sun, the cold was perishing. Huge quantities of powder snow fell when I was out there, and the skiing conditions were probably the best I have ever experienced.

February

This was another cold month which brought more snow to much of the country. However, it wasn’t as cold as January and in the Chiltern region the snowfalls were much lighter than the ones in December and January.  The mild Atlantic flow was often blocked, but the bitterly cold air to the north and east was never quite able to make it to the UK.

Winter 2009-10 was a memorable one for much of Britain with long spells of cold weather and heavy falls of snow. In some ways, it was reminiscent of 1981, with December bringing the most wintry conditions to my area. 

The Central England Temperature (CET) was 2.5C, which is 1.57C below the 1961-90 average and 2.13C below the 1981-2010 norm. The breakdown by month:

December 3.1C

January 1.5C

February 2.9C

It was also the second consecutive cold winter in the UK, and historical data suggests that cold winters often occur in clusters, so it's quite likely that we will experience several more in the next decade.

Issued 07/04/2010 © Brian Gaze (Updated 06/11/2023)

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