UK Climate Rankings
Local authority areas ranked by the fewest days recording 20mm or more of rainfall in 24 hours between January 2023 and December 2025.
This list ranks 20 UK local authority areas by the fewest days recording 20mm or more of rainfall in a single 24-hour window between January 2023 and December 2025. A 20mm day is the threshold the Met Office and the Environment Agency commonly use to define a "heavy rainfall" day. Counting heavy-rainfall days rather than total annual rainfall is a better signal for surface-water flooding, drainage stress, and the kind of weather that disrupts everyday life. Two areas can have similar annual totals but very different distributions, and the area with fewer concentrated downpours is the drier place to live in any practical sense.
The figures come from the Open-Meteo daily archive, which combines ECMWF ERA5 reanalysis with regional observation networks at roughly 11km resolution. Each council is queried at the centroid of its area and aggregated to a single per-area heavy-rainfall day count. ERA5 systematically overstates total rainfall over upland and rural cells, so this ranking counts threshold days rather than millimetre totals. Threshold counts are less sensitive to that bias.
The driest parts of the UK sit in the rain-shadow of higher ground to the west. East Anglia, the south-east, parts of the East Midlands, and the eastern fringes of Yorkshire and Lincolnshire all benefit from prevailing south-westerly weather having dropped much of its moisture over Welsh and west-of-England uplands before reaching them. Cambridge and the surrounding fenland is the driest sustained climate zone in the UK, averaging around 550mm of annual rainfall in long-run records. The wettest UK areas (the western Scottish Highlands, parts of Snowdonia, and the Lake District) can record more than 3000mm in the same year.
A low heavy-rainfall day count does not mean a low drought or water-stress risk. The opposite is closer to the truth: the south-east and East Anglia have the lowest annual rainfall in the UK and have experienced repeat hosepipe restrictions and water company drought-plan activations over the last decade. Low rainfall can also concentrate pollutants in slow-moving rivers, reduce groundwater recharge, and amplify the shrink-swell subsidence cycle on clay soils. For an address-specific picture, check the LocalRisk postcode page, which combines rainfall data with flood, subsidence, and water-stress signals.
This ranking does not measure surface-water flood risk, which depends on local drainage capacity and topography as much as on rainfall totals. It does not measure river-flood or coastal-flood risk, which are driven by catchment-scale and tidal factors. For those, use the Environment Agency's flood-risk service or the LocalRisk postcode page, which combines all three.
LocalRisk uses the Met Office and Environment Agency convention of 20mm or more in a 24-hour period. That threshold reliably triggers surface-water flooding in poorly drained areas and overwhelms the drainage capacity of older urban sewers in many parts of the country. Lower thresholds (5mm or 10mm) capture far more days but include routine drizzle that has little practical impact.
Threshold-day counts are more informative for flooding and everyday weather impact. Two areas can record similar annual totals from very different distributions: one with frequent light rain, one with a handful of concentrated downpours. The downpour-heavy area faces more surface-water flooding and drainage stress, even though the totals match. Threshold-day counts also reduce the effect of the ERA5 high-rainfall bias in upland and rural areas.
Open-Meteo's daily archive, which combines ECMWF ERA5 reanalysis with regional observation networks at approximately 11km resolution. The full archive runs from 1940 to within the last 24 hours; LocalRisk uses the January 2023 to December 2025 window so the figures reflect recent weather rather than long-run climatology. The Met Office's own 1991-2020 station climate normals are the authoritative long-run reference and broadly track the same regional pattern.
No. Surface-water flood risk depends on local drainage capacity and topography as well as rainfall. Many dry-climate council areas have urban districts with high surface-water flood risk because of older drainage systems and the way rainfall concentrates in short bursts when it does fall. For an address-specific picture, use the LocalRisk postcode page, which combines rainfall, river flood, surface-water flood, and coastal flood signals.
UKCP18 climate projections suggest UK summers are likely to become hotter and drier on average and winters milder and wetter, with the dry-summer trend most pronounced in the south and east. That points to existing dry areas seeing more pronounced summer drought and higher heatwave frequency in coming decades, while winter rainfall (when it falls) becomes more intense. The ranking shown here reflects recent observed weather and is the right starting point; UKCP18 projections are the long-run forecast.