England & Wales Precipitation Annual Stats – 2016
By Paul Homewood
Time to look at the the latest England & Wales Precipitation stats, now that the annual numbers are out for last year.
Last year ended pretty much average with 960mm. This compares to a long term mean of 918mm, and ranks the year at 161 out of 251 (rank 1 being the driest).
The wettest year was 1872, followed by 1768.
There is evidence of clustering of very wet years, but no evidence of anything remotely unusual about recent years.
There does seem to be more of a pattern when we look at very dry years however:
1788 and 1921 stand out as exceptionally dry years. But there were several other unusually dry ones in the 18th and 19thC.
You have to go back to 1973 to find the last year with less than 750mm. By contrast, there were 17 other such years prior to then, an average of one every 12 years.
We can also analyse monthly extremes. Below is a chart showing all months where precipitation exceeded 150mm.
By far the wettest month was October 1903, when 218mm fell. The wettest month in recent years was November 2009, with 192mm.
Again, I can see no evidence of anything unusual occurring in the last decade or so. There is a suggestion, though, that very wet months were not as common prior to the 20thC.
This can be better seen by looking at the number of months >150mm per decade. The latest ten years is shown for comparison:
On average, it is fair to say that it is a little bit wetter now than it used to be in the early 19thC. But above all it is the year to year variability which dominates the record, just as it always has.