Autumn 2000 Western Europe floods

The rainfall for this period in the three preceding years had been above the 1961-1990 average.[14] The previous spring was unsettled, with April and May particularly wet,[8] which increased the aquifer recharge season.[14] Heavy rain was also seen in June, leading to high river levels and some flooding in Yorkshire.[8]

September 2000 was generally unsettled, with wet periods between 14 and 19. This resulted in some flooding on 15 September around Portsmouth and Southsea as a pumping station at Eastney failed after 58 mm (2.3 in) of rain fell in 4.5 hours, being the heaviest rain since 1986 in the area. Total rainfall was also measured at 65mm in Havant making this a 1 in 108 year storm event.[15] Storms affected Flanders in Belgium 15 September, with tornados reported in the municipalities of Zwalm, Antwerp and Erpe-Mere. Flooding affected the regions of Ghent and Kortrijk.[16] 24 out of 27 UK Met Office regions except northern Scotland received higher than normal rainfall during the month, making this the wettest September since 1981.[5]

Ex-Hurricane Isaac crossed the Atlantic with eye still visible on 2 October[17] and lashed the west of the British isles with near gale-force winds on 3 October, before merging with another extra-tropical low on 4 October towards the north of Scotland.[18] Early October 2000 brought more than the monthly average rainfall in the first 10 days to the southeast of England.[19]

A complex of low pressures, named Heidrun & Imke[22] by FU Berlin formed from the remnants of Tropical Storm Leslie. This formed at 30˚N 76˚W on 5 October, swept westwards and merged with a front on 7 October, and then reintensified to become a storm south of Great Britain with winds of 40-50 knots reported in the Bay of Biscay.[23] An area of convective storms stalled over Sussex and Kent.

• 9 October: two complex low pressure systems brought more fronts and 25-40mm of rain over Sussex
• 10 October: a Low developed over Scotland, with gales and heavy showers over Sussex bringing 10-15mm of rain
• 11 October: the Low over Scotland became stuck, with a new Low arriving over Central England, producing gales over the whole UK and 15-30mm of rain over Sussex.
• 12 October: the Low drew moist air from the Bay of Biscay over Southern England where a line of heavy, localised thundery showers formed. They tracked northwest over Sussex, bringing 150mm of rain overnight to Uckfield. Only 5-10mm fell in some other areas.[24]

Homes in Yalding and Maidstone were flooded, however there had been fears that a high tide might lead to the River Medway bursting its banks. This threat passed preventing much more widespread damage.[25] Evacuations took place in some villages in the county.

On 12 October many roads were flooded across both West and East Sussex including the A21 and A22. A lifeboat crew rescued 20 people trapped in a supermarket in Uckfield and others were rescued by helicopter.[26]

Shrewsbury, Ironbridge and Bridgnorth flooded as the Severn breached its banks and reached its highest levels in 53 years.[27]

The Severn breached its banks in many parts of the county, including at Bewdley, Worcester and Upton-upon-Severn. In Worcester, the Severn peaked on 3 November at its highest level in 53 years. The river remained in flood for several days however and the main road bridge in the city was closed. Homes were flooded in Diglis as well as many businesses on the city's waterfront and the cricket ground. In Bewdley, the floods led to renewed calls for flood defences in the town.[28] These were completed in 2006 and have since reduced the impact of flooding on the town.

The Ouse in flood, York

Flooding affected York during the summer and autumn of 2000 as the River Ouse reached its highest levels since records began. The floods cost the city council in excess of £1 million and 40 people had to be moved from their homes.[29] The floods were the worst in 375 years; more than 300 homes were flooded and the army were called in to help with flood relief efforts.[30]

Defra commissioned an independent review by the Institution of Civil Engineers under George Fleming.[32] The review was to consider methods of estimating and reducing flood risk and look at whether flood risk management could make more use of natural processes. The resulting report entitled Learning to Live with Rivers specifically criticised a reluctance to use computer models and inadequate representation of the dynamic effects of land use, catchment processes and climatic variability. More broadly, the report noted that sustainable flood risk management could only be achieved by working with the natural response of the river basin and by providing the necessary storage, flow reduction and discharge capacity. It concluded that floods can only be managed, not prevented, and the community must learn to live with rivers.

The report found that damage was reduced by flood defences and by timely warnings and evacuations where the defences could not hold back the water. As a result, 280,000 properties were protected from the floods, but over 10,000 properties were still flooded at an estimated cost of £1 billion.