Deep freeze

The extensive snow caused travel disruption with roads, railways and airports all struggling to cope. Freezing conditions continued into the Christmas period with severe frosts and heavy snow in some areas.

December 2010 was the coldest across the UK since the national series began in 1910. The mean temperature for the UK was -1.0 °C, well below the long term average of 4.2 °C. The previous coldest December in the series was 0.1 °C, in 1981. The onset of the cold weather from late November was highlighted well in advance using our monthly forecasts. Since the wintry weather set in, our website had millions of visits every day, peaking on 20 December when our web pages were viewed around 13 million times. December also saw the highest number of visits to our website for a single month with more than 44.5 million visits more than double for an average month.

"...December also saw the highest number of visits to our website for a single month with more than 44.5 million visits - more than double for an average month."

Our Customer Centre answered 5,000 calls in just over a week; with 1,019 calls in a single day on 29 November. Our iPhone application received 32 million hits in November. Our press office took nearly 200 media calls each day. We also issued a daily weather 'story' on our website to supplement routine forecasts and warnings.

Regular briefings

Our Public Weather Service Advisors provided regular briefings to emergency responders across the country. We supplied regular forecasts to many local authorities and the Highways Agency. Met Office forecasters operating from the Highways Agency control centre helped to keep the nation's roads safe and moving. Our OpenRoad service provided advice on road surface temperature to road engineers across the UK.

We issued aviation warnings and forecasts as part of our Civil Aviation Authority contract, supplemented by commercial services. For example, some airlines and airports used our OpenRunway system which offers 24-hour access to forecast information such as runway temperature, rain and snow amount all vital in determining the right time to apply anti- or de-icer.

We continued to provide operational services and severe weather warnings to the energy industry to help predict demand and plan resources. Several companies acknowledged our role in helping to maintain supplies during the severe spell. All 19,000 patients registered for the Met Office's Healthy Outlook® service for Chronic Obstructive Pulmonary Disease (COPD), were warned of the cold spell well in advance (see page 11 for more on Healthy Outlook®). Working with the Department of Health and the Department for Work and Pensions, we produced and distributed a postcard to GP surgeries offering advice on winter weather services (COPD, winter fuel, cold weather payments) for vulnerable members of the public.

Accurate predictions

Forecasting snow, and accurately predicting where it will fall, poses a tough challenge but our forecasters provided very good advice for 12 out of 13 big weather patterns that blasted the UK this winter which is an outstanding performance. The high number of snowfall events over a prolonged period created an incredibly busy time for our weather experts.

The cold spell isn't a sign of things to come as it is all part of natural variability. Before last year we've had a run of mild winters in the UK, while globally 2010 was one of the warmest years on record, set in the context of long-term climate change and shorter term natural variability.

Normally, our winds come from the west keeping our winters relatively mild. However, during November (like last winter) a large area of high pressure in the Atlantic caused a 'block' to the westerly winds that tend to keep us that little bit milder. This allowed very cold Arctic air to move south across mainland Europe, giving us the coldest December on record.

• Find out more about how we performed during the Big Freeze