On 18 July, the Met Office contacted the Environment Agency's National Flood Warning Duty Officer to provide early warning of a severe rainfall event expected between 19 and 21 July. A number of severe weather warnings were then issued by the Met Office during this period.
Typically, these warnings provided information on the geographical areas and watercourses likely to be affected by the severe weather, the amount of rainfall expected, the timing of the anticipated severe weather event, and the Met Office's degree of confidence in the forecast.
The following extracts are examples of the information provided by the Met Office in its severe weather warnings.
Date Time Event 19 July 05.37 Event 0900 to 2000 on 19/7. Low confidence for Welsh Mountains, Welsh/Shropshire Hills, Severn Lowlands, Central, Staffs and High Peak, Trent Lowland, Avon/Soar Headwaters of 10mm or more in 1 hour, 15 or more in 6 hours, 20 mm or more in 12 hours. 19 July 20.25 Event 0900 to 2000 on 19/7. High confidence for Welsh Mountains, Welsh/Shropshire Hills, Severn Lowlands, Central, Staffs and High Peak, Trent Lowland, Avon/Soar Headwaters of 15mm or more in 6 hours, 20 mm or more in 12 hours. 20 July 16.56 Event 2100 on 19/7 to 0900 on 21/9. High confidence for Welsh Mountains, Welsh/Shropshire Hills, Severn Lowlands, Central, Staffs and High Peak, Trent Lowland, Avon/Soar Headwaters of 15mm or more in 6 hours, 20 mm or more in 12 hours.
The Environment Agency has procedures in place to ensure that Regional Forecasting Duty Officers translate the Met Office heavy rainfall warnings into forecasts of river levels and flows.
These are used to inform decisions on whether to issue flood warnings and/or carry out specific operational activities.