As the Earth continues its never-ending journey around the Sun our weather never ceases in its desire to redistribute the sun’s heat evenly across our planet. As it does so every year it can truly show us its raw power bringing floods, heatwaves, devastating winds, tornadoes and hurricanes and the year of 2011 was no different.
The year started with very heavy rain, flooding and landslides in parts of Australia, Brazil and much of Sri Lanka. Flooding was widespread across Queensland from end of December 2010 to January 2011 with several separate periods of heavy rain causing rivers to rise over many days. Many places, including Condamine and Chinchilla were inundated by flood waters on multiple occasions.
At the time Adam Sciafe, Head of Seasonal to Decadal Prediction at the Met Office, explained the link between these floods and La Niña.
The situation in western Australia did not get much better as Severe Tropical cyclone Yasi struck Queensland at the start of February bringing damaging winds in excess of 120mph and heavy rain to coastal and island communities between Cape Flattery and Prosperpine. Although Yasi came ashore north of where the worst of the recent flooding occurred, it was a large cyclone and so affected a wide area including some of the previously flooded regions. The very heavy rains continued as it moved inland towards central parts of Australia.
April saw the UK experience its warmest April on record with many parts having temperatures 3 to 5 °C warmer than normal. The UK average temperature was 10.7 °C exceeding the previous warmest April on record of 10.2 °C in 2007. Much of the country had a fine Easter weekend. It was also the warmest Spring on record for the UK with a mean temperature of 9.15C which beat the previous record of 9.05C in 2007.
In May the Missouri town of Joplin was ravaged by the worst tornado in 50 years. The tornado was the deadliest since 1953, and the second tornado disaster in the US in less than a month. The twister cut a six-mile swath through the centre of the town, wrecking churches, schools, businesses and homes. The town’s fire department estimated that up to a third of buildings in the town were damaged or destroyed.
In June China evacuated more than 500,000 people from deadly floods that are devastating areas in the south of the country. This followed the worst drought in 50 years across the region. At least 105 people have been swept to their deaths or killed in landslides and another 65 were left missing after rivers burst their banks.
In July focus switched to the US as a swath of America from the Mexican border to Boston suffered under dangerously hot temperatures. The combination of high temperatures and excessive humidity triggered health warnings across the country.
This excessive heat was closely followed in August by Hurricane Irene, the first hurricane of this year’s North Atlantic tropical storm season. Irene headed for the Bahamas and then moved in to the United States, making landfall over North Carolina before passing over New York City. Considerable damage occurred in eastern upstate New York and Vermont, which suffered from the worst flooding in centuries.
In September a deep area of low pressure which contained post-tropical storm Katia brought gales and heavy rain to parts of the UK. It is unusual for tropical storms to keep their tropical identity as they move across the colder waters of the Atlantic and this storm was the most powerful ex-hurricane to reach the UK since Hurricane Lili in 1996. Bob Wilderspin, Met Offfice Chief Forecaster explained the situation as the storm arrived in the UK.
Tropical Cyclones continued to be the focus of our weather and at the end of September Typhoon Roke hit Japan’s south-west coast and then moved north-east over Tokyo, to the region affected by the devastating earthquake and tsunami earlier in the year.
The end of September and the start of October saw a heatwave in the UK give record high temperatures. A new UK October record was set when temperatures peaked at 29.9 °C, at Gravesend in Kent, beating the previous record of 29.4 °C recorded in the village of March in Cambridgeshire, which had stood since 1 October 1985. Wales also has a new national record, 28.2 °C was recorded at Hawarden, Flintshire. The previous record was 26.4 °C recorded at Ruthin, Denbighshire, again on 1 October 1985.
The Philippines were battered by many typhoons this year. In October Typhoons Nesat and Nalgae struck the islands in just one week, bringing torrential rain and winds of up to 150mph.
Late October saw a snowstorm strike the US north-east causing unprecedented damage to woodlands and parks, with 1,500 trees lost in New York City alone. The storm, which broke record snowfall levels for October, left millions without power and 11 dead.
Across the UK there were some really big regional variations in rainfall this year, with parts of the Midlands and East Anglia seeing record or near record low amounts of rainfall during the Spring and in Autumn, while parts of Scotland had near record amounts of rainfall. The differences in rainfall across the UK can be clearly seen on the map below, and many parts of the southeast remained in drought in December.
Major floods occurred during the 2011 monsoon season in Thailand. Provinces in the Chao Phraya and Mekong River basin, including Bangkok and surrounding areas were most severely affected directly or indirectly by inundation. Flooding also affected most provinces in Thailand’s south. Flooding began around July 2011, and continued into December 2011. Over 12.8 million people were affected and about six million hectares of land inundated with flood water.
November saw a powerful Bering Sea storm hit western Alaska with winds of up to 80mph – the strongest the state has seen in nearly 40 years. Meanwhile Ottawa, Canada, broke its record for the warmest November on record. The average maximum temperature was 9.9C, which is way above the usual maximum temperature of 4.8C in November. The previous warmest November was in 1948 where temperatures averaged 8.7C. The recent warmth resulted in Ottawa also breaking its record for the warmest autumn.
Typhoon Washi hit the southern Philippine island of Mindanao late in December causing flash floods and landslides which killed about 1,000 people and left tens of thousands homeless.
A severe storm affected the UK on December 8. Gusts of 165mph were recorded on Cairngorm summit during the storm. This is the highest recorded gust in the UK since 6 November 1996 when Cairngorm recorded 168 mph – and not far short of the UK record of 173 mph set here on 20 March 1986.
In stark contrast to last year the UK had a mild Christmas with a top temperature of 15.1 °C at Aberdeen on Christmas Day. This was only half a degree shy of the warmest Christmas Day on record – 15.6 °C at Leith in Scotland and Killerton, Devon in England. This compares to Christmas day last year where parts of Wales struggled to get any warmer than -7.6 °C – highlighting the differences that we can see in our weather from one year to the next.