Within London, both the City of London and the City of Westminster have city status and both the City of London and the remainder of Greater London are counties for the purposes of lieutenancies.[129] The area of Greater London has incorporated areas that were once part of the historic counties of Middlesex, Kent, Surrey, Essex and Hertfordshire.[130] London's status as the capital of England, and later the United Kingdom, has never been granted or confirmed officially—by statute or in written form.[note 6]
Its position was formed through constitutional convention, making its status as de facto capital a part of the UK's unwritten constitution. The capital of England was moved to London from Winchester as the Palace of Westminster developed in the 12th and 13th centuries to become the permanent location of the royal court, and thus the political capital of the nation.[134] More recently, Greater London has been defined as a region of England and in this context is known as London.[10]
London has a temperate oceanic climate (Köppen: Cfb ), similar to all of southern Britain. Despite its reputation as being a rainy city, London receives less precipitation (601 mm, 24 in, in a year) than Rome, Bordeaux, Toulouse, Naples, Sydney and New York.[140][141][142][143][144][145][146] Temperature extremes for all sites in the London area range from 38.1 °C (100.6 °F) at Kew during August 2003 [147] down to −16.1 °C (3.0 °F) at Northolt during January 1962.[148]
Summers are generally warm and sometimes hot. London's average July high is 24 °C (75.2 °F). On average London will see 31 days above 25 °C (77.0 °F) each year, and 4.2 days above 30.0 °C (86.0 °F) every year. During the 2003 European heat wave there were 14 consecutive days above 30 °C (86.0 °F) and 2 consecutive days where temperatures reached 38 °C (100.4 °F), leading to hundreds of heat related deaths.[149]
Winters are generally cool and damp with little temperature variation. Snowfall occurs occasionally and can cause travel disruption when this happens. Snowfall is more common in outer London. Spring and autumn are mixed seasons and can be pleasant. As a large city, London has a considerable urban heat island effect,[150] making the centre of London at times 5 °C (9 °F) warmer than the suburbs and outskirts. The effect of this can be seen below when comparing London Heathrow, 15 miles west of London, with the London Weather Centre, in the city centre.[151]
| Climate data for London Heathrow (1981–2010, extremes 1948–present) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Record high °C (°F) | 17.2 (63) | 19.8 (67.6) | 24.2 (75.6) | 29.4 (84.9) | 32.8 (91) | 35.6 (96.1) | 36.7 (98.1) | 38.1 (100.6) | 35.4 (95.7) | 29.9 (85.8) | 20.8 (69.4) | 17.4 (63.3) | 38.1 (100.6) |
| Average high °C (°F) | 8.1 (46.6) | 8.4 (47.1) | 11.3 (52.3) | 14.2 (57.6) | 17.9 (64.2) | 21.0 (69.8) | 23.5 (74.3) | 23.2 (73.8) | 19.9 (67.8) | 15.5 (59.9) | 11.1 (52) | 8.3 (46.9) | 15.2 (59.4) |
| Average low °C (°F) | 2.3 (36.1) | 2.1 (35.8) | 3.9 (39) | 5.5 (41.9) | 8.7 (47.7) | 11.7 (53.1) | 13.9 (57) | 13.7 (56.7) | 11.4 (52.5) | 8.4 (47.1) | 4.9 (40.8) | 2.7 (36.9) | 7.5 (45.5) |
| Record low °C (°F) | −13.2 (8.2) | −9.6 (14.7) | −5.1 (22.8) | −2.6 (27.3) | −0.9 (30.4) | 1.5 (34.7) | 5.6 (42.1) | 5.9 (42.6) | 1.8 (35.2) | −3.3 (26.1) | −7.0 (19.4) | −11.8 (10.8) | −13.2 (8.2) |
| Average precipitation mm (inches) | 55.2 (2.173) | 40.9 (1.61) | 41.6 (1.638) | 43.7 (1.72) | 49.4 (1.945) | 45.1 (1.776) | 44.5 (1.752) | 49.5 (1.949) | 49.1 (1.933) | 68.5 (2.697) | 59.0 (2.323) | 55.2 (2.173) | 601.7 (23.689) |
| Average precipitation days (≥ 1.0 mm) | 11.1 | 8.5 | 9.3 | 9.1 | 8.8 | 8.2 | 7.7 | 7.5 | 8.1 | 10.8 | 10.3 | 10.2 | 109.5 |
| Mean monthly sunshine hours | 61.5 | 77.9 | 114.6 | 168.7 | 198.5 | 204.3 | 212.0 | 204.7 | 149.3 | 116.5 | 72.6 | 52.0 | 1,632.6 |
| Source: [152][153]
For more station data near London, see Geography of London.
| |||||||||||||
| [hide]Climate data for London Weather Centre | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Average high °C (°F) | 8.5 (47.3) | 8.9 (48) | 11.7 (53.1) | 15.7 (60.3) | 18.6 (65.5) | 22.4 (72.3) | 23.6 (74.5) | 23.2 (73.8) | 20.8 (69.4) | 16.1 (61) | 11.9 (53.4) | 8.6 (47.5) | 15.8 (60.4) |
| Daily mean °C (°F) | 6.8 (44.2) | 6.8 (44.2) | 8.8 (47.8) | 12.0 (53.6) | 14.8 (58.6) | 18.3 (64.9) | 19.6 (67.3) | 19.4 (66.9) | 17.3 (63.1) | 13.5 (56.3) | 10.0 (50) | 7.0 (44.6) | 12.8 (55) |
| Average low °C (°F) | 5.0 (41) | 4.7 (40.5) | 5.8 (42.4) | 8.2 (46.8) | 10.9 (51.6) | 14.1 (57.4) | 15.5 (59.9) | 15.5 (59.9) | 13.7 (56.7) | 10.9 (51.6) | 8.0 (46.4) | 5.4 (41.7) | 9.8 (49.6) |
| Source #1: [154] | |||||||||||||
| Source #2: [155] | |||||||||||||
