March heralded an unusually wintry and remarkably cold start to spring 2018. Spells of mild and wet weather were interrupted by two periods of snow, ice and blizzard conditions that brought widespread disruption. Across the UK, monthly mean temperatures generally registered more than 1.5°C below average. A minimum temperature of -10.7°C was recorded at Cawdor Castle (Nairnshire) on the 1st. In contrast with the very dry February, March rainfall for the UK was notably above average, exceptionally so in southern England and the Midlands which received almost twice the average. In contrast, north-west England and western Scotland received less than 75% of the average. River flows were generally above normal with exceptionally high flows recorded in south-west England and south-east Scotland. Conversely, some catchments in western Scotland and Northern Ireland registered around half of the average. Reservoir stocks were above average in all but a few northern impoundments and many in the south continued to recover from the unseasonably low stocks recorded at the beginning of the year (e.g. Bewl was at full capacity by the end of March). Seasonal recovery of groundwater levels continued at most sites and levels were generally in the normal range or higher, apart from in the slower responding Chalk of south-east England. Overall, wet weather late in the recharge season has significantly improved the outlook for the remainder of spring and summer 2018. In localised parts of the Chalk aquifer (e.g. the Chilterns) low groundwater levels and river flows may persist, although current low flows and levels are not exceptional.
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