Wettest and rainiest places in the UK

A closer look at the top 10

The top 10 is a split between western Scotland and southern Wales, with no English entries at all. Argyll and Bute leads at 2,218mm a year, roughly 1.9x the UK average of 1,163mm. Stirling follows at 2,078mm, then Rhondda Cynon Taf (2,020), Inverclyde (1,995), Gwynedd (1,863), Highland (1,851), Neath Port Talbot (1,789), Merthyr Tydfil (1,743), North Ayrshire (1,713) and Bridgend (1,654).

The reason is geography. Prevailing westerly winds carry moisture off the Atlantic and dump it on the first bit of high ground they hit; western Scotland and the South Wales valleys are exactly that first high ground. This is orographic rainfall, and it is why the western half of the UK gets so much more rain than the eastern half despite being at the same latitude.

Rainfall totals and rain days do not line up perfectly. Argyll and Bute has the most total rain but not the most rainy days; Highland has 211 rain days across 1,851mm, which averages heavier individual falls per rainy day than Rhondda Cynon Taf's 181 days across 2,020mm. Some western areas get their rain in fewer, more intense bursts; others get near-daily drizzle that adds up more slowly.

The east-west split across the country is one of the biggest divides in UK climate. Argyll and Bute at 2,218mm sits at one end of the spectrum; the driest areas in the East of England receive under 550mm, which is less than a quarter of Argyll's total. Two areas at the same latitude but 400 miles apart can experience entirely different weather.