[summer '85]

Here's a list of the wettest and driest months for each decade in the EWR series from 1766

2000s (up to May 2007)
Wettest: 188.0mm Oct 2000 Driest: 9.5mm Apr 2007
1990s
Wettest: 172.1mm Dec 1993 Driest: 9.1mm Aug 1995
1980s
Wettest: 180.2mm Oct 1987 Driest: 10.8mm Apr 1984
1970s
Wettest: 178.6mm Nov 1970 Driest: 14.3mm Apr 1974
1960s
Wettest: 173.1mm Dec 1965 Driest: 15.7mm Mar 1961
1950s
Wettest: 180.4mm Nov 1951 Driest: 8.0mm Sept 1959
1940s
Wettest: 196.5mm Nov 1940 Driest: 11.1mm Mar 1944
1930s
Wettest: 183.5mm Dec 1934 Driest: 7.1mm Apr 1938
1920s
Wettest: 195.9mm Nov 1929 Driest: 4.3mm Jun 1925
1910s
Wettest: 192.9mm Aug 1912 Driest: 9.0mm Apr 1912
1900s
Wettest: 218.1mm Oct 1903 Driest: 22.5mm May 1905
1890s
Wettest: 162.3mm Oct 1891 Driest: 3.6mm Feb 1891
1880s
Wettest: 162.6mm Oct 1882 Driest: 16.2mm Jan 1880
1870s
Wettest: 193.9mm Dec 1876 Driest: 21.5mm Apr 1870
1860s
Wettest: 185.6mm Dec 1868 Driest: 9.5mm Sept 1865
1850s
Wettest: 202.5mm Nov 1852 Driest: 14.1mm Apr 1854
1840s
Wettest: 160.9mm Nov 1842 Driest: 7.9mm May 1844
1830s
Wettest: 164.2mm Jul 1834 Driest: 16.0mm May 1836
1820s
Wettest: 182.6mm Jul 1828 Driest: 8.2mm Jul 1825
1810s
Wettest: 177.4mm Nov 1810 Driest: 7.9mm Apr 1817
1800s
Wettest: 145.8mm Nov 1800, Dec 1803 Driest: 9.1mm Jul 1800
1790s
Wettest: 192.1mm Aug 1799 Driest: 12.9mm Sept 1795
1780s
Wettest: 155.0mm Jul 1787 Driest: 5.6mm Mar 1781
1770s
Wettest: 200.8mm Nov 1770 Driest: 13.5mm Feb 1779
1760s from 1766
Wettest: 148.7mm Jun 1768 Driest: 4.4mm Jan 1766

[mianfei]

Really notable cases in the list:

summer said:

1900s
Wettest: 218.1mm Oct 1903 Driest: 22.5mm May 1905…

1870s
Wettest: 193.9mm Dec 1876 Driest: 21.5mm Apr 1870…
1800s
Wettest: 145.8mm Nov 1800, Dec 1803 Driest: 9.1mm Jul 1800

The 1900s is the really surprising one, since apart from the very wet year of 1903 there was no exceptional rainfall, yet not one month under 20 millimetres occurred all decade.

It’s interesting to note that in 1902 there was only 49 millimetres difference between the wettest and driest months of the year, which is scarcely more than the difference between the driest (April with 58 millimetres) and wettest (October with 95 millimetres) monthly average in the EWP series. September 1907, it is interesting to see, was shaded as the driest month of the decade by a mere 0.1 millimetre.

The other two cases, in contrast, are quite predictable from the annual rainfall averages. After 1870 - which but for a very wet October would have been the third driest year behind 1788 and 1921 - wet weather set in and very dry spells were absent until the freezing winter of 1879/1880, whilst the 1800s were the driest decade in the EWP series with an average of only 837 millimetres.

The 1780s might also be though interesting since even the very wet years of 1782 and 1789 did not have a month with more than 150.8 milliemetres of August 1782. 1782, however, had four other months with between 125 and 150 millimetres:

• April with 139mm (record until 2000)
• May with 142.4mm (not equalled since)
• July with 131.7mm
• September with 128.1mm

This post has been edited by mianfei: 12 May 2012 - 05:45