UK under snow
© MODISIreland and UK from space on Christmas Day 2010.
A long range weather forecaster is predicting an early start to winter 2011-2012 for many regions of the United Kingdom and Ireland. James Madden of Exacta Weather says heavy snowfalls are likely in places as soon as late October and early November.

Last week, UK-based Positive Weather Solutions also predicted that the winter months will be colder than average everywhere and that some regions will experience significantly colder than average temperatures between December and March.

The agency, which has a relatively high success rate in its long range weather predictions, has also given a 36% chance of the Ireland and Britain experiencing a White Christmas. This prediction in reflected in the latest odds from William Hill Bookmakers who have given shortened odds of snow falling on Christmas Day.

The bookmaker have also given odds of 16/1 that the lowest recorded temperature in England will be beaten (-26.1C, Jan 10 1982, Shropshire), and even odds of 100/1 that Big Ben Fails to chime due to being frozen solid and that the Thames will freeze over between Westminster Bridge and Tower Bridge.

The chilly long range forecasts also follow the coolest summer since 1986 in many parts of Ireland and since 1962 in parts of the southwest. The highest temperature recorded this summer was 25.5°C at Oak Park, Co. Carlow on the 3rd of June.

Meanwhile, commenting on the autumn and winter months in his updated seasonal forecast (2 September), James Madden stated that the UK and Ireland can expect a cooler than average theme to continue as we head into autumn. He is predicting a notable increase in usual wind strengths for this time of year across many parts, that will result in frequent and potentially damaging gale force winds and strong stormy features throughout autumn and winter.

"Although some places further South may see some spells of settled weather at times, the general theme for autumn as a whole looks largely wet and very windy with dominant grey skies. It will be generally unsettled and turn progressively colder with an early start to winter, especially more so in the regions of Scotland, Northern England, and Northern Ireland", he said.

Madden's Winter Forecast

"As we head towards winter, I expect to see the first signs of some moderate to heavy snowfalls as early as October or November in certain parts of the UK. In terms of the meteorological winter, I expect December, January, and February to experience below average temperatures, with the heaviest snowfalls occurring within the time frame of November to January across many parts of the UK."

"The most important factor within our weather forecasting calculations is solar activity and other major natural factors that it influences. Radiant energy from the sun is the primary influence on both the earth's ocean and atmosphere."

"Low solar activity and ocean behaviour alter atmospheric circulation and block jet stream patterns that create enhanced moisture in terms of snowfall. The UK and Ireland is hit by prolonged periods of extreme cold and snow from the Arctic regions, as cold easterlies or north-easterlies develop. Huge swirly low pressure systems also offer the potential for widespread disruption from heavy snowfall across many parts of the UK including the South, as they clash with the predominant cold air over the UK."

"Coupled with other in depth factors such as recent volcanic activity and changes to the Gulf Stream/North Atlantic drift that we consider, this does not bode well for the severity of the UK and Northern European winter of winter 2011-12. Frequent and prolonged cold spells with heavy dumps of snow from blizzard like conditions is likely across many parts of the UK. The areas we expect to be worse hit throughout include the vast majority of Scotland and the Scottish Highlands, Northern England, and Northern Ireland. We have particular concerns as to the huge implications that this may pose to the infrastructure of the UK and Ireland transportation systems/economy."

A continuation of the cycle of severe wintry weather?

Though overall temperatures during the past two winters have been close to or slightly below normal for the season, both Ireland and the UK did experience periods of extreme weather.

Late November and December 2010 brought prolonged periods of cold weather leading to significant disruption to traffic and travel. Castlederg recorded a Northern Ireland record low temperature of −18.7 °C (−1.7 °F) on the morning of 23rd December 2010, while mercury levels dipped to minus 17.5c in Straide, Co Mayo on Christmas morning. December 2010 also was the coldest December across the UK since the national series began in 1910, according to the UK Met Office.

The "Big Freeze" of November/December 2010 also saw record low temperatures being broken.

Ireland Prepares For Wintry Weather

The National Roads Authority (NRA) has ordered an additional 80,000 tonnes of rock salt to treat the country's national road network during winter 2011-2012. An NRA spokesperson told Irish Weather Online (IWO) that the supplies, which are scheduled to arrive from North Africa during the coming weeks, are in addition to existing grit supplies totalling 70,000 tonnes.

Sean O'Neill stated that a tender had been advertised on etenders.gov.ie for the supply of a further 40,000 tonnes of rock salt to be supplied to local authorities to assist them in their efforts to treat non-national routes.

"We used approximately 115,000 tonnes of grit to treat the national network last winter, which we would consider an unusually cold season compared to average winters in Ireland. In previous years we have not been required to use more than 50-60,000 tonnes of grit", he said.

Mr. O'Neill noted that the decision to order additional rock salt supplies was made in light of an anticipated rise in demand for supplies closer to the coming winter as well as improved shipping conditions at this time of the year.

Meanwhile, local authorities across the country have already started preparing for any possible repeat of last winter's Big Freeze. Dozens of additional salt barns are being constructed throughout the country while the storage capacity of many other existing facilities is being increased. Cork County Council has also submitted a tender for the purchase of Winter Maintenance Salt Spreaders and to carry out alterations to Council Trucks.

Elsewhere, the Dublin Airport Authority has already set about securing De-icing Materials for its airports at Dublin, Cork and Shannon.