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UPDATE AT 10pm on Monday 29th Nov

Bradford Lister park recorded minus 7.5C; the coldest November night since records began in 1908.

Linton on Ouse recorded its coldest November night too with minus 11.2C. Remarkably on November 4th the same station recorded its highest daytime November temperature with 17.6C.

Linton on Ouse also recorded this morning at 9am the deepest November lying snow on record at 15cm.

It's been a remarkable night across our region, and the UK, with records tumbling. I haven't access to the full climate records as I am writing this from home, so I don't know the year in which most of the previous records were set.

But here in Yorkshire, Church Fenton recorded minus 13C. This site previously held the record for the coldest November night on record for Yorkshire as a whole, with minus 11.9C.

Now Topcliffe in North Yorkshire holds that record, having recorded minus 14C last night.

Waddington in Lincolnshire also broke its all time November record with minus 8C.

Data for Waddington and Church Fenton go back to the mid 1940's.

Nationally some very low temperatures have also been recorded overnight, with new records in Scotland at Altnaharra with minus 14.4C and Loch Glascarnoch with minus 12.5C.

In Wales, Trawscoed recorded minus 12.5C, Sennybridge minus 15.6C.

In Shropshire, England, Shawbury recorded minus 13.2C and Newport minus 11.8C.

In Northern Ireland, Aldergrove has recorded minus 9C and that beats the previous November lowest (minus 6.6) back in 1962.

The cold weather will be with us all next week. For Yorkshire and Lincolnshire as a strong easterly wind picks up early next week snow showers will become frequent at times, and could be driven as far west as the Pennines. Severe drifting is expected, especially over the hills in the east.

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It has been the earliest spell of cold weather and snow to envelop the whole of the UK since 1993. But it hasn't been the earliest snow locally; in fact here in Yorkshire we have had snow in November on several occasions since 1993.

And spare a thought for Spain and Portugal. The jet stream will steer very active weather systems through this area, leading to prolonged heavy rain which is almost certain to lead to some flooding, as was the case last winter.

So far snowfall has been confined mainly to more eastern areas of our area with snow showers pushed southwards on the prevailing wind.

A subtle but noticeable change will occur in the next 12 hours though, with the wind changing direction to the northeast.

The source of the air flowing across the UK this weekend in Northern Russia where temperatures are around minus 25C. We have the North Sea to thank for modifying this air mass as it comes south-westwards.

Snow showers are likely to develop readily as this cold air comes across the North Sea. The main area of uncertainty in this weekends forecast is the strength of the wind which will be crucial in determining how far west the showers get.

The chart below illustrates the problem well.

Notice the North Sea, coloured green and blue which indicates the computer expects precipitation to develop. But all models have a weakness in that they are unable to move convective showers at any one grid point with the steering wind flow. Hence all models invariably underestimate the penetration of showers inland.

There could also be small scale disturbances which develop in the cold air/warm sea boundary which could lead to more organisation of the snow showers which is very difficult to predict.

So this weekend expect snow showers (possibly rain or sleet right along the coast) to affect eastern areas, which could be frequent - and at times, as the wind picks up, these snow showers will be driven well inland.

Next week there will be a classic battle between low pressure and milder air in the south, and high pressure and colder air to the north as the chart for Tuesday shows.

Where the 2 meet, significant snowfall is likely. Will the cold air hang on, or will the milder air win? This is very much open to question, with quite a few models disagreeing on this aspect. But expect strong bitter easterlies to develop next week as the battle commences.

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The first wintry night of the season may pose problems for some commuters across parts of Yorkshire and Lincolnshire in the morning.

Showers already running down the North Sea and into coastal areas will gradually move inland through tonight as the steering flow veers more to the Northeast. Most of the showers will be of rain or sleet at first, but turn steadily to snow, even down to low levels.

The exception may be low lying areas near the coast. The sea temperature is still around 10C, and although this will provide a lot of energy for the showers, it will also act, except in heavier showers, to melt falling snow back to sleet or rain at times.

Because of the showery nature of the precipitation, the distribution of snow will differ from place to place. But as a general rule most places away from the coast will wake up in the morning to up to 2cms of snow, with some areas, caught in a line of showers, seeing around 5cms.

Worst hit areas will be in more Eastern parts of the region - parts of the North York Moors and Yorkshire Wolds, for example, where 10cm or more is possible by the end of the night.

Widespread ice will be an added hazard.

Looking further ahead, although further wintry showers are likely through tomorrow and Friday, it's the weekend and early next week that could be more significant.

The chart below for midday Saturday shows low pressure to the south of the UK, with high pressure further north.

It's a classic 'blocking' pattern, leading to an East or Northeasterly wind, coming straight from Northern Russia. The air over the weekend will become unusually cold for this time of the year, with showers of snow even along the coast. Significant snowfall is possible.

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Winter looks set to come early to the UK with very cold air expected to sweep southwards across most areas by the end of the week and into next weekend.

By Saturday, the air will be unusually cold for November and with still relatively warm seas, all the ingredients are there for some heavy falls of snow, even at low levels.

The dark blue line shown on the chart below gives an indication of the thickness, and hence coldness of the air. It is rare to see air any colder than this at our latitude at this time of the year.

The mechanism for heavy snow will be through a process called 'potential instability'.

As deep cold air flows across the warmer sea it forces the warmer air in contact with the sea aloft. The warmer air cools quickly as it rises, condensing into clouds. The precipitation then falls back through the deep cold air, turning quickly to snow.

The activity of the showers that form is directly proportional to the contrast in temperature between the sea surface and the mass of air flowing south, and it is in these very situations that not only is heavy snow produced, but thunder is sometimes reported too, such is the energy of the cumulonimbus clouds which develop.

As ever the devil will be in the detail and will be crucially dependent on the direction of the wind. At the moment eastern coastal counties look most prone to disruption, although it is likely that other areas could be affected too with troughs of low pressure bringing snow showers inland.

Timing of any disruption is unclear at this stage, as the air will get colder slowly from Wednesday onwards. At first snow is likely over hills, but towards the end of the week and into the weekend some snow is likely at all levels.

Most models are suggesting that the atmosphere will become slow moving and blocked with a very cold East or Northeasterly set up likely through much of next week .

Interestingly, early spells of intense cold so early in the season are not a reliable indicator of what the rest of winter may bring.

The old Yorkshire saying 'Ice in November to bear a duck, the rest of winter nowt but slush and muck' has proved to be one of the more reliable of the 'old wives tales' over the years.

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It was claimed by experts following the floods of Autumn 2000 that such rainfall events were a taste of things to come, with increased autumn and winter rainfall a central projection of climate models.

In fact, current forecasts for later this century suggest that parts of Yorkshire will see an increase in autumn and winter rainfall of between 10 and 20%, with obvious implications for river flooding.

And according to a study by Newcastle University, extreme rainfall events have become more frequent and intense over a forty year period across the UK, particularly in Scotland and the North of England. They studied rainfall statistics from 1961-2000.

They also suggest that the five million people who live next to rivers can expect to be flooded more regularly in the future.

The study found that the probability of an extreme five or ten day rainfall event during the 1990s, compared to the previous thirty year period, doubled in Northern England.

Additional analysis showed that extreme rainfall events that are expected to happen every fifty years increased in frequency and size in the North of England, especially in autumn.

The pattern of changes in extremes uncovered by the research matches the predictions made in a number of climate models. Dr Fowler, author of the study at Newcastle University, claims 'the changes in the 40 year period are consistent with the trend we would expect from global warming'.

But Philip Eden, one of the country's leading and most respected climatologists, argues that the claims could be misleading. The problem, he says, is down to the short period of rainfall statistics analysed.

He claims that by taking a much longer time period, for example the whole of the 20th century, the frequency of high intensity rainfall events that we have witnessed in the past 30 years is not unusual.

The eras of heaviest summer downpours have actually coincided with cooler summers, not warmer summers, in particular 1912-1931, and again from 1948-1969.

In autumn and winter, downpours are closely linked with the strength of westerlies, which were very low in the 1960s, the start point of the study, and reached a peak between 1988 and 2002, he continued.

That said there does seem to have been more incidences of flooding in the last couple of decades.

But could it be that this is more a function of urbanisation and flood plain development, than any significant increase in high intensity rainfall events?

And the media could have played their part in making us think that flooding is on the increase.

100 years ago we would have no idea if there had been flash floods in some parts of the country, but 24 news has changed all that and within hours pictures of floods from around the world are beamed into our living rooms.

This all adds to the perception that the frequency of serious floods are on the increase when it could be that its simply the awareness of flooding that has changed - coupled with the extensive flood plain development that we have witnessed in the last few decades.

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It's almost 10 years to the day since large parts of the UK experienced their worst floods on record. My house by the River Nidd in Knaresborough was one of literally thousands that got flooded during a 3 week period towards the end of October and into the first half of November which culminated in the evacuation of parts of York, as fears grew that the Foss barrier in York would overtop.

In fact the Autumn floods were a culmination of several very wet months, through Spring and Summer. April turned out to be the wettest since 1756 - quickly followed by May, the wettest since 1983.

By June the land was already on a knife edge and with further heavy rain through June, many rivers across Yorkshire were put on flood alert. The River Ouse rose to its highest ever June level, with Todmorden and Hebden Bridge suffering flooding from the River Calder.

The rest of Summer was average from a rainfall point of view, but crucially there were no decent dry spells and the land remained wet.

September and October were wet months, with a very mobile westerly pattern of weather becoming established. Atlantic depressions steamed in, with little more than 24 hours between weather fronts towards the end of October.

The North Atlantic was abnormally warm, adding moisture and energy to weather systems as they crossed the UK.

On the morning of Monday October 30th explosive development saw an area of low pressure deepen to 958mb, producing 2 inches of rain across the Pennines. As it departed through the Humber the coastguard recorded a gust of 99mph, with Hurricane force 12 winds in Sea area Humber.

Such was the rapid drop in pressure, snow and thunder were observed simultaneously over the Yorkshire Dales. An already sodden river catchment could take no more; and many of the regions rivers burst their banks.

Flooding was widespread across the UK, but Stockbridge in Keighley won the dubious accolade of having the highest concentration of flooded houses anywhere in Britain - 325. Houses along the River Don were ruined.

The River Ouse in York reached its highest levels since records began in 1642. And the towns of Malton and Norton, which had only just recovered from flooding in March 1999 were inundated once again.

In the end, September was the wettest since 1981; October the wettest since 1903 and November the wettest since 1970. Autumn was the wettest since 1872, and more rain fell in September, October and November than in any other 3 month period since rainfall records began in 1727.

Climatologically it was calculated that Autumn 2000 was a 1 in a 500 year event, assuming a static climate.

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