April is usually the driest month in our area, but I’m afraid this April continued the pattern of the previous months of this year with an above average rainfall of 72.8 mm. This total is 82 percent over the average for the area of 40.4 mm. That said, there were 14 days with no rainfall at all, which emphasizes that the periods of rain were often heavy.

It was another mild month; the average temperature was 10.3°C, which is 1.0°C above the average for the area. The highest daytime temperature was 20.1°C on the 11th.  Most nights were also mild with no air frosts and just 8 grass frosts. The coldest night was the 20th when the temperature fell to minus 0.1°C.

‘Kathleen’ on 6-7 April and ‘Noa’ on 11-12 April were this month’s named storms. They were named by the Irish and French Met Offices respectively and neither proved too severe in our area, although the north and west of the UK suffered strong winds and heavy rain. In our area I measured 40 mph gusts on 9 April and 17 mm of rain on 28 April. The sea-level atmospheric pressure rose to 1025 hPa on the 21st, falling to 975 hPa towards the end of the month. The average pressure was 1005 hPa. Winds were mainly from a westerly direction but turned easterly at the end of the month.

Despite the rain and cloud there were only three days without any sunshine and a total for the month of 109 hours, which is 33 percent below the average for April. This was 30 hours fewer than April 2023.

When is a storm not a storm?

There seem to have been rather a lot of named storms over the past few months, with two alone mentioned above. The legal definition defines a storm as being a high wind [1]. The Royal Meteorological Society [2] says it’s a weather system accompanied by strong winds and other destructive weather such as heavy rain, thunderstorms and/or hail. The Shipping Forecast defines storm force winds as having a mean wind speed of 55-63 mph over a ten-minute period or gusts to 70-78 mph. The Association of British Insurers states a storm should have winds gusting 55 mph, or torrential rainfall of a least 25 mm per hour, or rates of snowfall to at least 12 inches deep in 24 hours, or hail with a force to damage hard surfaces or break glass. Finally, the Met Office states a storm is a violent atmospheric disturbance, which may include fierce winds, thunderstorms, squalls, snow storms, hailstorms, etc. But what if you experience a violent atmospheric disturbance that causes damage necessitating an insurance claim and the Met Office has not declared it as a named storm – have you then suffered damage from a storm? 

This is precisely what has occurred to a well-known holiday business, which is claiming some £60 million worth of repairs from their insurers for damage from flooding (no high winds were involved). The insurers are only offering £25 million in reparation, this being their maximum payout for damages from a storm, which they claim was the cause of the damage. But the storm was not named so was it a storm or not?  The case continues…

[1] The Times Newspaper, accessed 01/05/2004

[2] The Royal Meteorological Society (2022), ‘Weather A-Z, London, The Natural History Museum, p. 104.

For local weather details and forecasts go to: https://offweather.hopto.org

Richard Seaton

rkseaton@outlook.com