Climate of London

The climate of London features a temperate oceanic climate (Cfb) and also exhibits attributes of a humid subtropical climate (Cfa) during the hotter summer months. Winters are generally cool to mild, and summers are warm to hot and extremely humid, with frequent precipitation all year round. London has a very rich history of meteorological observations, with precipitation records beginning as early as January 1697 at Kew Gardens. Irregular observations were made at multiple locations in the ensuing years. An observing station has been located at Greenwich since 1841, giving London its longest continuous reliable temperature series. Other stations include Heathrow, beginning in 1948, Hampstead, beginning in 1910, Northolt, beginning in 1948, and St James's Park, beginning in 1910.
The highest temperature ever observed in London is on 10 August 2003 and the lowest is 1 January 1962. The lowest daily maximum temperature is occurring on 3 occasions: 8 January 1841, 4 January 1867 and 12 January 1987. The highest daily minimum temperature recorded is on 29 July 1948. This is also the highest minimum temperature ever reported during the month of July in the United Kingdom. In addition to this, London holds multiple national records, including the record maximum for the months of February, April, May and June.
The city can sometimes experience extremes. Snowfall is a somewhat common occurrence in winter, falling on average 16 days per year, although it is infrequently heavy. Thunderstorms are a similarly rare feature, occurring on average 15 days per year. London has been known to experience tornadoes. Most recently an F2 struck Kensal Green on 7 December 2006.
Climate data tables.
Hampstead - Weather Station in North London.
The weather station enclosure is the most elevated of any in the London area, and as a result daytime temperatures are typically one degree lower than Heathrow, Kew, Northolt and Greenwich.
Northolt - Airfield Weather Station in the North West of London.
Temperature extremes range from in August 2003, down to in January 1962.