Figures and text updated 4 October 2016 with provisional full month data.
Despite a mixture of weather across the UK, two warm spells around the 9th and 13th of the month helped boost temperatures, with this September provisionally the equal-second warmest for the UK since records began in 1910. Provisional stats show the mean temperature for September to be 14.6C tied with 1949 but behind 2006 (15.2C).
The first month of autumn started on an unsettled note, but then a southerly airflow bringing warm air from the continent allowed temperatures to climb. This led to the warmest day of the year on the 13th when 34.4C was recorded at Gravesend in Kent. It’s quite unusual to see temperatures this high so late in the year. The last time the hottest day of the year was recorded in September was in 1954 with 30.0C recorded at Regents Park, London on the first day of the month. However, we have to go back to 1926 to find the last time the warmest day of the year occurred this late in the year (31.7C Hunstanton, Norfolk on 19 September).
The image below shows that mean temperatures were 1.5-2.5C above the 30-year average across many parts of the UK, but that eastern parts were almost 3C above average. Sunshine hours echoed this pattern with amounts above average in eastern parts. Skies were cloudier in the west, but sunshine hours were still not far off average.
|September 2016 Provisional||Maximum temperature||Minimum temperature||Mean temperature|
|Actual deg C||Anm||Actual deg C||Anm||Actual deg C||Anm|
The heat did trigger some spectacular thunderstorms and there were spells of rain both early and late in the month with some western areas exceeding their monthly average. However, some areas were much drier, particularly in the east of Scotland and southeast England. Overall, provisional rainfall figures for the month are close to average with 98.9mm recorded compared to the September average of 96.4mm.
|September 2016 Provisional||Sunshine hours||Rainfall|
|Actual hours||Anm %||Actual mm||Anm %|
September 2016 ended up the fifth warmest in the central England temperature [CET] series that began in 1659. I reckon the mean temperature for the month was 16.05°C, and the anomaly +2.53°C above the 1961-1990 long-term average. It never quite matched 2006 and almost caught 1949, and after all’s said and done that only makes it the warmest since 2006, the warmest September in the series!