According to John Kettley, 11th September 1999 was the warmest September day in central London since 1973
Maxima recorded on the 11th September 1999
30.4C at Gravesend
30.0C at Southend
29.5C at London Weather Centre
29.4C at Northolt
29.4C at Bedford
29.3C at Marham
29.0C at Cambridge
28.5C at Cranwell
28.4C at Benson
28.4C at Manston
MANCHESTER SUMMER INDEX for 2021: 238
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