Weather Stories

by Ian Currie, editor of Weather Eye magazine

April: It was not only a warmer and drier than normal month but we had the bonus of it being sunnier than average too

It was just two years ago that we experienced nationally the warmest April since at least the days of Oliver Cromwell back in the seventeenth century.

So, to record another very mild April this year is quite outstanding.  Apart from  2007 we have to go back to 1865 for comparable warmth though 1943 and 1987 were almost as warm in the London area.

There were no real exceptionally hot days with the highest value around 21C in central London on the 15th and 22nd and further afield 22C near Maidstone in Kent.

The temperature soared to as high as 29C around Easter in 1949. This year it was really the persistence of mild weather with very few cool days. The temperature stayed below 10C on the 27th away from the heart of London but many places failed to record an air frost for the first time since 1993 and unlike last year there was no snow.  Some places recorded their coldest night as late as the 29th.

Rainfall was below average with north London having less than 50 per cent. On the 16th a stationary front produced some quite heavy, showery bursts of rain. There was even a rumble or two of thunder with the heaviest falls of over 12mm to the south of Croydon. Here monthly averages were nearer 70 per cent.

It was not only a warmer and drier than normal month but we had the bonus of it being sunnier than average too by some 20 per cent or more though Easter was quite a cloudy, misty affair.

So, April 2009 can be regarded as quite a pleasant spring month that brought a steady rise of soil temperatures and proved a good growing month.

March: Was a sunny and warm month, but clear night skies meant that we had some frosty evenings.

It was a fairly gloomy last day of March but overall it was one of the sunniest on record and most of London enjoyed over 150 hours of bright sunshine though this well short of years such as 1907 and 1995 when over 180 hours were measured.

The sun helped to boost day time temperatures by up to one and a half degrees C above average but clear night skies meant ground frosts on half the nights and an air frost as late as the 30th.

Sunshine apart it was a month of few extremes but an active frontal system crossing London on the 3rd produced a very wet day with 21mm in just 12 hours near Croydon and 23mm at Coulsdon was the wettest March day since 1984. In spite of this, rainfall for London was below par by the month's end especially across northern suburbs with just 50 per cent of the long term mean and 75 per cent on the southern fringes.

March is known for its 'Many weathers' and the 28th was a very good example with very unstable polar air over London. One minute it was sunny,  the next dark and squally with stinging bursts of hail. There were even reports of lightning and thunder in southern suburbs.

There is an old saying which tells us 'thunder in spring, cold will bring' and the night that followed was indeed very chilly with a coating of frost adorning parks and gardens by morning and the temperature fell to minus 4C in downland valleys just outside of London.

Early on the 5th March snow fell quite widely in the southwest of England and further east across the Cotswolds and Salisbury Plain and a light covering was seen on the higher parts of some south London Boroughs such as Croydon and Sutton.

This meant that some places in the London area have observed snow lying on the ground on one or more days in each of the successive months October 2008 to March 2009 and this has not happened since 1887/88.