Autumn 2011 United Kingdom heat wave
High pressure caused warm air from Southern Europe to rise up towards the UK
Dates	25 September - 3 October
Areas affected	United Kingdom United Kingdom The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...  and Ireland Republic of Ireland Ireland , described as the Republic of Ireland , is a sovereign state in Europe occupying approximately five-sixths of the island of the same name. Its capital is Dublin. Ireland, which had a population of 4.58 million in 2011, is a constitutional republic governed as a parliamentary democracy,...
Highest temperature	29.9°C in Gravesend Gravesend, Kent Gravesend is a town in northwest Kent, England, on the south bank of the Thames, opposite Tilbury in Essex. It is the administrative town of the Borough of Gravesham and, because of its geographical position, has always had an important role to play in the history and communications of this part of... , England England England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

The Autumn 2011 United Kingdom heat wave was a period of unseasonably hot weather which arrived towards the end of September 2011 and continued into October. As a result, record high temperatures for the country were broken for the autumn months. The Autumn heat wave followed the warmest temperatures to occur on record in the Spring, but also the coolest temperatures to occur in the Summer months since 1993.

The exceptional hot and dry weather was first announced on the 23 and 24 September, with forecasters predicting that the United Kingdom

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

's hottest autumn days since 1985 would occur. At that point, temperatures in the UK were expected to reach at least 27°C in the following days, 15° above average for the time of year. The reason given for the upcoming heat wave was high pressure levels drifting northwards from Europe

Europe

Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

. Temperatures were expected to peak in the country from 28 September - 2 October, at 28°C in South England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

 and 24°C in Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

. The warm weather was advertised as an "Indian summer

Indian summer

An Indian summer is a meteorological phenomenon that occurs in the autumn. It refers to a period of considerably above normal temperatures, accompanied by dry and hazy conditions, usually after there has been a killing frost...

" and with claims that Britain would become "hotter than Hawaii". However, cold northerly winds were predicted to return during the second week of October as the high pressure moved away, bringing much cooler and seasonal weather.

Temperatures in most parts of the United Kingdom began to rise on 25 September, reaching 23°C in some areas. The warm weather stayed consistent over the next few days and reached 27°C at Saint Helier

Saint Helier

Saint Helier is one of the twelve parishes of Jersey, the largest of the Channel Islands in the English Channel. St. Helier has a population of about 28,000, roughly 31.2% of the total population of Jersey, and is the capital of the Island . The urban area of the parish of St...

 in Jersey

Jersey

Jersey, officially the Bailiwick of Jersey is a British Crown Dependency off the coast of Normandy, France. As well as the island of Jersey itself, the bailiwick includes two groups of small islands that are no longer permanently inhabited, the Minquiers and Écréhous, and the Pierres de Lecq and...

 on 28 September. Temperatures continued to rise and the temperatures recorded on the 29 September exceeded those peaked in Costa del Sol

Costa del Sol

The Costa del Sol is a region in the south of Spain, in the autonomous community of Andalusia, comprising the coastal towns and communities along the Mediterranean coastline of the Málaga province. The Costa del Sol is situated between two lesser known costas: Costa de la Luz and Costa Tropical...

, Turkey

Turkey

Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe...

 and Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

 that day at 29°C in Lincolnshire

Lincolnshire

Lincolnshire is a county in the east of England. It borders Norfolk to the south east, Cambridgeshire to the south, Rutland to the south west, Leicestershire and Nottinghamshire to the west, South Yorkshire to the north west, and the East Riding of Yorkshire to the north. It also borders...

. This also broke the UK's record high for that day of the year, with 27°C having been recorded in York

York

York is a walled city, situated at the confluence of the Rivers Ouse and Foss in North Yorkshire, England. The city has a rich heritage and has provided the backdrop to major political events throughout much of its two millennia of existence...

 in 1985. 1 October brought the highest temperatures of the heat wave with 30°C recorded in Gravesend, Kent

Gravesend, Kent

Gravesend is a town in northwest Kent, England, on the south bank of the Thames, opposite Tilbury in Essex. It is the administrative town of the Borough of Gravesham and, because of its geographical position, has always had an important role to play in the history and communications of this part of...

, the highest ever recorded in the United Kingdom for October, beating the previous October record of 29°C which was also set in 1985 in Cambridgeshire

Cambridgeshire

Cambridgeshire is a county in England, bordering Lincolnshire to the north, Norfolk to the northeast, Suffolk to the east, Essex and Hertfordshire to the south, and Bedfordshire and Northamptonshire to the west...

. The new record also made the first day of October the third warmest of 2011. From 4 October, temperatures finally began to drop in most areas of the country, but remained fairly mild and above average for October. By the end of the month, October 2011 became the UK's seventh warmest since records began.

Effects

The unseasonably warm weather in the United Kingdom saw visitor numbers in Chester Zoo

Chester Zoo

Chester Zoo is a zoological garden at Upton-by-Chester, in Cheshire, England. It was opened in 1931 by George Mottershead and his family, who used as a basis some animals reported to have come from an earlier zoo in Shavington. It is one of the UK's largest zoos at...

 rise by 149% on 28 September. The heat wave also saw an increase of camping and caravan parks and hotel bookings in parts of the country, including Wales

Wales

Wales is a country that is part of the United Kingdom and the island of Great Britain, bordered by England to its east and the Atlantic Ocean and Irish Sea to its west. It has a population of three million, and a total area of 20,779 km²...

. Businesses in Winchester

Winchester

Winchester is a historic cathedral city and former capital city of England. It is the county town of Hampshire, in South East England. The city lies at the heart of the wider City of Winchester, a local government district, and is located at the western end of the South Downs, along the course of...

 have also been said to have been favoured during the period, as a 67% tourism increase was recorded on 30 September from the same day in 2010. A negative effect for many UK businesses was a sales drop, and some clothing retailers suffered their largest for two years, as autumn and winter clothing sales decreased.

The BBC

BBC

The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...

 claimed that the unseasonable heat wave caused for low Strictly Come Dancing

Strictly Come Dancing

Strictly Come Dancing is a British television show, featuring celebrities with professional dance partners competing in Ballroom and Latin dances. The title of the show suggests a continuation of the long-running series Come Dancing, with an allusion to the film Strictly Ballroom...

 on 30 September, with a alleged loss of one million viewers on the Friday in question. A similar pattern followed the following evening with X Factor

The X Factor (UK)

The X Factor is a British television music competition to find new singing talent. Created by Simon Cowell, it began in September 2004 and is contested by aspiring singers drawn from public auditions. It is the originator of the international X Factor franchise. The seven series of the show to date...

 on ITV

ITV

ITV is the major commercial public service TV network in the United Kingdom. Launched in 1955 under the auspices of the Independent Television Authority to provide competition to the BBC, it is also the oldest commercial network in the UK...

.