Storm overflows spike to four times normal as thunderstorms hit England and Wales

Mason's ledger flagged 76 storm overflows discharging across England and Wales at an hour when the normal reading is 18 — more than four times the typical rate. The reporting gathered here does not give a live overflow count from the Environment Agency or water companies, but it does document exactly the kind of weather event that produces spikes like this: successive days of thunderstorm warnings, intense rainfall, and flooding hitting the ground after a prolonged drought. According to [1], West Midlands Fire Service was called out to "significant flooding" in Birmingham's Perry Barr area after a flood warning was issued overnight due to rising river levels, with crews responding to incidents on Curbar Road, Thornbridge Avenue and Haddon Road. Birmingham City Council urged residents to avoid walking, cycling or driving through flood water, according to [1]. The flooding coincided with two yellow thunderstorm warnings covering London and the South East, and a much larger area spanning Wales and much of England, running from 5am to 10pm, according to [1]. The Environment Agency had issued 22 flood alerts across the Midlands and South East, the report states. Met Office forecaster Craig Snell told [1] that some areas could see more than 75mm of rain in 12 hours, with the Midlands and Wales facing a "quite wet" day and further thunderstorms possible moving into the South East by evening. A second report, [2], describes a closely related pattern of back-to-back yellow warnings — one from 3am to 10pm on a Wednesday and a further warning beginning 6am Thursday running to 10pm — covering an overlapping footprint of London, the South East, the Midlands, East Anglia, the North West, South West and large parts of Wales. The Met Office, as cited in [2], warned of rainfall rates of 20-30mm in under an hour, with some locations facing 40-50mm in two to three hours and up to 50mm over 12 hours on the Thursday. Such intensity, [2] notes, is enough to overwhelm drainage systems and produce surface water flooding. Both reports stress that this rain fell on ground already parched: [1] records that drought had been declared across nearly three-quarters of England and the whole of Wales after five heatwaves and record temperatures up to 38.1C in London, while [2] describes the shift from "prolonged heat and dryness" to intense storms. That combination — hard, dry ground and sudden heavy downpours — is a recognised driver of higher runoff into combined sewers, which is consistent with, though not proof of, the overflow spike Wayne's instruments picked up. Neither [1] nor [2] contains overflow, sewer or Environment Agency discharge-monitoring data directly, so the 76-versus-18 reading cannot be tied to a specific outfall or water company from this material alone. What the sources do establish is a live, multi-day thunderstorm event with confirmed flash flooding in Birmingham and flood alerts across two regions, providing plausible weather context for the spike rather than a confirmed causal chain. What to watch: whether the Environment Agency or affected water companies publish overflow event duration data for this period, which would confirm whether the spike tracks the storm timing precisely.