April Past Events
April is a month that we often regard as being relatively Spring like; with the days getting lighter, buds are usually well developed on trees and other foiliage by mid month. Although we think of it as a relatively benign month that produces April showers we also expect plenty of relatively warm sunshine in between and assume that prolonged rainfall events are rather rare.
Suffice to say then that there will always be April’s that go against such expectations and 1998 provided just such an example. April 1998 was a very wet month. In fact it was notable for being the wettest month since 1818 across England and Wales, with 138mm falling on average but it was also quite cold and sunless as well.
It will probably be best remembered for the severe flooding that developed over the Midlands and East Anglia just before Easter on April 9th however. Synoptic charts for the period show that a frontal zone lay across the area, with a relatively narrow band of precipitation separating very cold polar air to the northwest from much warmer, moist tropical air to the southeast. A further surge of Arctic air plunged southwards across Britain on the 9th, bringing snow showers to Scotland and northern England. On reaching the frontal zone, this cold air helped to strengthen the set up, with a cold northerly flow to its north and a warm moist southerly flow to its south, locking the rain belt in situ for more than 24 hours.
Rainfall totals exceeded 50mm (2 inches) for the 3 day period between the 8th-10th April, over a broad swathe of the south Midlands. In Worcestershire, RAF Pershore reported 80mm (3.1 inches) of rainfall in 24 hours, with estimates that locally as much as 100mm may have fallen over the Cotswolds; that is as much as two months worth of rain. The River Avon at Evesham (Gloucs), rose a huge 4.7 metres, causing flooding up to a mile from the river, with the River Leam at Royal Leamington Spa (Warcs) also rising nearly 3 metres causing extensive flooding. Stratford-upon-Avon (Warcs) was also badly affected, and more than 1,500 people were evacuated from their homes in the area. Many cars were left abandoned as well, which perhaps suggests that there was little warning of the event or understanding of the likely scale or impact of the event.
The Environment Agency estimated that at both Evesham and Royal Leamington Spa, the floods were a once in a 150 year event. The floods were responsible for five fatalities and estimates of the losses by industry suggested figures of around £750 million for economic damage and around £600 million for insured damage (Benfield Greig Group, Munich Re) making the event the fourth most costly UK major weather disaster since records began in 1960, at the time.
After the depression finally moved away, colder air finally pushed further south with widespread snow showers until the 15th, leading to a relatively rare ‘white Easter’ in some places. North Wales saw particularly heavy snowfalls on the 10-11th with Mold (Clywd) reporting as much as 37cm of level snow by the 14th April.
In fact April 1998 was colder than March, an event which is relatively rare. All in all, partly as a result of such temperature contrasts at this time of the year, it is clear that April is not necessarily a benign month at all.
Ref: The UK floods of Easter 1998, Mark Saunders, University College, London, April 1998
