November 2009 was, by any account, a wet month. Rainfall was around 190% across England and Wales but as high as 250% across NW England and central and southern Scotland. The only exception to this was East Anglia where rainfall was closer to average. However temperatures were above average overall & up to around 2.5C above average across the SE of England and East Anglia. Whilst maximum temperatures ended up slightly above average it was minimum temperatures that were generally well up on the average, with the incidence of frost well below average. The highest temperature of the month was reported at Heathrow (London) & Gravesend (Kent) on the 1st with 17.4C, whilst the lowest was tied, both Braemar (Aberdeenshire) and Cromdale (Highland) saw -8.6C on the 9th. Sunshine was well below average in the western UK but above average elsewhere especially eastern districts where 125% was reported.

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November begun mild, wet and quite windy: there were gusts

A short but dramatic cold snap gripped the UK for a few days during mid-November 2004 bringing with it some quite widespread falls of snow to parts of the UK and some bitterly cold temperatures.

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On the 18th November a developing low on the wave of an old front separating relatively warm, moist air to the south and colder, drier polar air to the north brought a large area of rainfall across the UK throughout the day which edged slowly south-eastwards. To the north of the front across Scotland it was a fairly cold but mainly dry day with a few sleet and snow showers moving into Shetland, Orkney and the far Northeast of Scotland. It was though a thoroughly wet day for central parts of England and Wales with as much as an inch of rain (25mm) falling under the slow moving front. During the afternoon the much colder polar air to the north began to undercut the warm air lying over central areas - turning the rain readily to snow, catching forecasters and the

The period from the 10-12th of March 2011 has seen large temperature difference across the north with snow across southern Scotland and N Ireland but much milder air to the south. Something very similar happened almost exactly five years ago when there was disruption due to heavy snow on the 12th March 2006 as Atlantic fronts stalled against a well-established cold block across Scandinavia that extended towards the UK. A very cold air mass moved westward on the 11th to cover all but Ireland and Northern Ireland. On the 12th, the Atlantic fronts stalled across Wales, Northwest England and Southwest Scotland bringing some significant falls of snow to these areas overnight and during the morning of the 12th. A significant contrast in temperature was maintained across the Irish Sea throughout the day; under the persistent cloud and snow some parts of Northern England struggled to rise above freezing, the lowest maxima are outlined in Table 1 below. However, across the Irish Sea in parts of

May is perhaps surprisingly one of the least cyclonic months of the year and is a month to be savoured- the ‘darling buds of May’ are usually well opened by mid month on the trees and shrubs are well into new leaf. The longer light evenings can really make it feel that summer is just around the corner.

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However, this pleasant picture is not always the case and there have been occasions when May has in fact been nothing but downright dismal. The period from May 9th to the 14th is Buchan's third cold spell (see our glossary for more on Buchan’s spells) and there is some evidence for this period holding up.

Recently we have been lucky enough to have some very reasonable May’s and the last poor one was as long ago as 1996. This was an unusually cold month, some 2C colder than average; in fact only 1902 was colder in recent times. The month started with cool north easterlies covering the country and low pressure to the south west over Biscay and high

By the late May Bank Holiday weekend we expect or at least hope for some decent weather. That of May 2007 however was sadly noteworthy for how unsettled it became. The origin of the deep depression that caused this was on Friday 25th May right over the Davis Strait across the Atlantic. caused by a combination of a weak surface low and a strengthening jet moving SE out of Northern Canada. The low looked set to combine with increased baroclinicity and deepen and then develop as a deepening low across the southern UK- over the Bank Holiday weekend.

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March is a month that we tend to expect to be rather spring-like but it can still pack quite a punch. We have all heard the expression ‘that it comes in like a lion and goes out like a lamb’. There is probably some truth in this but the reality is that the end of March can still be very unsettled indeed.

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March 2004 was one such month that saw a very unsettled end to it. A disturbed weather pattern ensued during the weekend of the 20th March 2004 as a mobile moist westerly flow covered the country. From mid month a stream of depressions had run north east, north of Scotland. By the 18th, as high pressure affected the south, it appeared that there might be a lull in the stormy weather. The quieter period was short lived however, as by the 19th a deep secondary low developed west of Ireland and then ran east across northern England. Wet and very windy weather spread across the UK with winds gusting up to 70 mph in places and parts of Wales, especially Capel

The disruptive frontal snowfall on the weekend of the 11th-12th March 2006

By mid March its time to think about Spring being in the air isn't it? However, Mid March 2006 saw the winter return with vengeance. Atlantic fronts stalled against a well-established cold block across Scandinavia around the 12th, and a very cold air mass moved westward to cover all but Ireland and Northern Ireland. Any milder air was stopped from progressing further east as Atlantic fronts stalled across Wales, Northwest England and Southwest Scotland bringing some significant falls of snow to these areas overnight and during the morning of the 12th. A significant contrast in temperature was maintained across the Irish Sea throughout the day; under the persistent cloud and snow some parts of Northern England struggled to rise above freezing, the lowest maxima are outlined in Table 1 below. However, across the Irish Sea in parts of Ireland in the milder Atlantic air mass it was very mild

We are increasingly hearing the term 'Spanish plume' used by the popular media now. This feature is not that uncommon in some warm summers, whilst in some others they are almost completely absent. Basically they occur when a plume of very warm air is advected north from the Iberian area reaching the UK on a southerly airflow but this is usually replaced fairly quickly by cooler weather moving east from the Atlantic with a cold front seperating the two air masses. When the two air masses meet, the very warm 'plume' air is forced to rise vigorously over the cooler Atlantic air and as a result produces thunderstorms. Storms may well coalesce and can give widespread, heavy rainfall, with hail.

A very good example of a classic spanish plume occurred on the 18th-19th June 2005. A very warm and moist air mass was advected north across the majority of the UK through the period. There was unabated sunshine in the clear skies initially across much of the UK with a very warm upper plume of

June usually takes it place in the meteorological calendar as the first ‘summer’ month (even though summer does not officially begin until after the summer solstice around June 21^st).

Although we may think of June as a warm month it is not often that it is especially settled. Even in the warmest Junes however long spells of dry, fine weather can be broken by the outbreak of thunderstorms, which may lead to some quite severe weather in places.

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Quite often the thundery weather is initiated by what you might hear being discussed as a ‘spanish plume’ event. During the summer months high level ‘plumes’ of warm air that originate over the Iberian peninsula can move north, across the Bay of Biscay and through Western France and eventually up into the British Isles. These plumes generally contain high dew points and also notably high temperatures in the first couple of thousand metres of the atmosphere.

The summer of 1976 was the hottest ever recorded in the UK with a CET (mean temperature across representative stations across central England) of 17.8C but the reason it occurred started long before June 1976, which was the first of the three very warm settled summer months. A period of dry spring weather enabled the dry ground to absorb solar radiation very efficiently and heat up rapidly by day as a result. In fact, a warm June is quite an unusual event; we see the hottest day of the year in June only a quarter of the time and there has been little sign of any long term warming trend recently in June; if anything it has become duller and wetter. The hottest June on record in 1976 wasn't that much warmer than the average July or August but nevertheless it is certainly remembered as being hot. This is perhaps partly as a result of the fact that the hottest weather occured in the last ten days of the month but it was quite dry and warm beforehand.

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