Christmas Weather 2011 - A White One Or Not?

[Paul]

Latest update to the Xmas forecast now online :smiliz19:

http://www.netweather.tv/index.cgi?action=other;type=xmas;sess=

[The Northern Ramper]

Cold ramper

[johnholmes]

I'll be posting week 11 of my marathon items using the two CFS outputs tomorrow evening assuming I get time, if not then during Thursday.

For those who want to believe in Santa Claus, the chart Paul shows is more or less what the anomaly monthly charts are showing this week. More cold than mild and a surprising number of times with low pressure over or NE of the UK. The current set, see link below show what I mean.

http://www.netweathe...4410a5b8093f86a

Question for Paul?

The anomaly charts have updated, temperature and pressure on almost every day this week-is this usual? I thought they only updated once per week?

cheers

John

Edited November 15, 2011 by johnholmes

[Paul]

That's correct John, they're now updating daily - this isn't just raw output though it's a rolling average from the previous 7 days so it's not jumping about or anything crazy. We'll shortly be bringing some additional features on line with some probablistic forecasts and some ensemble style graphs/maps etc again all using the rolling 7 day data set.

[johnholmes]

That's correct John, they're now updating daily - this isn't just raw output though it's a rolling average from the previous 7 days so it's not jumping about or anything crazy. We'll shortly be bringing some additional features on line with some probablistic forecasts and some ensemble style graphs/maps etc again all using the rolling 7 day data set.

thanks that explains why the last 4 or 5, with minor changes, all seem to be showing very similar type charts. Perhaps I need then to compare a set of temperature and pressure anomaly charts on the same day each week to see how they are changing rather than every day as I do now?

[Paul]

I quite like following the subtle changes, but certainly picking a day a week could be a way to use it too. We'll have some ensemble type graphs and postage stamp maps up soon which will aid in seeing what's changing and hopefully following what the over-riding trend may be.

[Coast]

Bookmakers have slashed the odds of a white Christmas as weather experts forecast the UK will be struck by an Arctic blast of wintry weather throughout December. Ladbrokes have today halved the betting odds of a white Christmas in London from 10/1 to 5/1 and the chances of snow on the ground on December 25 in Newcastle upon Tyne are just 3/1.

Weather forecasters believe the UK's unusually warm November temperatures will be replaced by a polar cold front that will bring with it snow and icy conditions. The most likely regions of the UK to experience a white Christmas are Scotland, the North East of England and the Eastern coast. The Midlands, the South West and Wales are forecast to escape the worst of the extreme conditions.

Ladbrokes spokesman Alex Donohue told ClickGreen that despite the current spell of warmer-than-usual temperatures, the bookmaker's inhouse weather experts were predicting a return to a big chill in December. “This year has been a year of extremes in terms of the weather,†he added. “Our weather team is seeing a change from the beginning of December and that is strongly increasing the chances of snow for Christmas. “As a result the odds of a white Christmas have definitely come in today.â€

And Jonathan Powell, senior forecaster at Positive Weather Solutions, agreed, saying a new weather system was likely to move in over the UK from the beginning of December, which would trigger the start of an icy spell. He added: “November will continue to be mild and dry, but the long-range forecast reveals wintry conditions in the North and the East from the first week in December. “It will likely most affect the North of the UK including the North East of England and the Eastern side of the country. “South of there, through the Midlands and North Wales, should escape the worst of the weather.†“As this polar air moves in to replace the milder conditions, any rain that comes in with it will likely fall as snow. “There is definitely a much greater chance of a white Christmas than usual.â€

http://www.clickgreen.org.uk/news/national-news/122791-odds-halved-on-a-white-christmas-as-weather-forecast-shows-polar-blast-for-uk.html

[I remember Atlantic 252]

cfs on weatheronline suggests now a high pressure dominated Xmas period, high over Scotland on 28th Dec,

[rich1]

cfs on weatheronline suggests now a high pressure dominated Xmas period, high over Scotland on 28th Dec,

If we cant have snow, a bit of anticyclonic frost and fog will suit me fine. Think 1995 was the last time I saw any of that down here

Last year was probably the best year for Xmas weather down here in my memory, a thickish coating of snow and a max of -1 degrees that lay until the 27th-28th. 2009 was chilly and sunny [snow melted on the 23rd], 2004 was cold and sunny [before disgusting mild wet weather invaded before the new year]. A healthy portion of meh describes every other year except perhaps 2000 [turned colder through the day] and 1996 [snow showers in the morning] and 1993 [cold with light snow showers early]

This year? Find some encouragement that people havent given up on December yet, for me its hard to tell but a blocking anticyclone with inversion frosts could be a punt. Will be in Fife this year for Christmas, but a 3rd white Xmas for the north in succession may be a bit of a stretch. First time for everything though, an ENE wind would do the business there

Oh and had just seen Mr Datas historical chart from 1906, which had an even warmer Euro High firmly in control round the 23rd November. That year had a big blizzard setting up on Xmas and boxing day with cold weather lasting to the new year according to reports. Not a believer in pattern matching as such but does show how colder weather this year in December is still very possible at this point

Edited November 16, 2011 by rich1

[johnholmes]

week 11 of the will it be cold/snowy at Christmas and an overall look each day at what the raw CFS output each day suggests for winter.

Also a look at the CFS anomaly charts.

Note the post above from Paul about the change that occurred, I think, this week. They are now issued each day as a rolling set of charts.

For you cold lovers they do give another view of how winter MIGHT turn out.

I said MIGHT-remember all the charts shown on this post come with a very strong jh health warning!

But enjoy anyway.

Week 12 next week and getting near to being able to link in with some of the further out teleconnections to see what they may be suggesting as we near the start of winter officially.

CFS for the winter with jh-issue 11-wed 16nov 2011.pdf

Edited November 16, 2011 by johnholmes

[Stuart]

Not so good

Forecast

Our thirteenth update makes no change to the chances of Christmas snow in the north and south. The weather patterns so far during November have remained blocked, with a mild southerly flow. The mild weather looks set to continue for a while at least, and there are currently few signs of an early winter developing. The current Christmas forecast is for mostly mild to average temperatures with winds coming from the west or south west.

Probabilities of snow falling on Christmas Day

North of Yorkshire / Lancashire: 20%

South of Yorkshire / Lancashire: 15%

Forecast issued

Update 1, 01/09/2011

Update 2, 10/09/2011

Update 3, 13/09/2011

Update 4, 17/09/2011

Update 5, 25/09/2011

Update 6, 01/10/2011

Update 7, 08/10/2011

Update 8, 16/10/2011

Update 9, 23/10/2011

Update 10, 30/10/2011

Update 11, 06/11/2011

Update 12, 13/11/2011

Update 13, 20/11/2011

http://theweatheroutlook.com/forecast/Christmas-weather-forecast

[Coast]

Latest odds from the bookies:

No White Christmas in London:

1/6, 1/7 1/19 and 17/100 from various online sources

Yes to a White Christmas in London:

7/2, 4/1, 7/1 and 24/5 again from various sites.

Belfast gets 1/10 for no White Christmas and 147/50 for a White Christmas

http://www.oddschecker.com/specials/other-specials/christmas-specials/white-christmas/in-belfast

[Paul]

It's that time of the week again, latest Xmas forecast now online :w00t:

http://www.netweather.tv/index.cgi?action=other;type=xmas;sess=

[BlueHedgehog074]

*gives Santa a double shake to ensure he is telling the truth*....... ;')

A 25% chance of snow for here. Not bad.

[johnholmes]

*gives Santa a double shake to ensure he is telling the truth*....... ;')

A 25% chance of snow for here. Not bad.

the chart Paul is using is the one issued on Sunday-this text is using the issue on Monday-just shows how quickly and also how often the raw CFS charts change

for December

_{Soon turning generally mild and unsettled after a mixed start, the mild lasting into 10-11th when a colder spell spread in from the west lasting out to the 14th when again turning milder and unsettled. Mixed and unsettled then until Christmas Eve when Santa decided to please all the cold and possibly snow lovers with a northerly behind a west to east tracking low! Gone by Boxing Day with milder air until 29th, briefly colder then a windy milder end to the year.}

_{full weekly update should be ready tomorrow, each day with the raw CFS for the winter and then the CFS anomaly charts for each month with comments.}

Edited November 22, 2011 by johnholmes

[BlueHedgehog074]

the chart Paul is using is the one issued on Sunday-this text is using the issue on Monday-just shows how quickly and also how often the raw CFS charts change

for December

_{Soon turning generally mild and unsettled after a mixed start, the mild lasting into 10-11th when a colder spell spread in from the west lasting out to the 14th when again turning milder and unsettled. Mixed and unsettled then until Christmas Eve when Santa decided to please all the cold and possibly snow lovers with a northerly behind a west to east tracking low! Gone by Boxing Day with milder air until 29th, briefly colder then a windy milder end to the year.}

_{full weekly update should be ready tomorrow, each day with the raw CFS for the winter and then the CFS anomaly charts for each month with comments.}

Ah, thanks for that. And I have to agree with how much the CFS charts change sometimes. I remember once viewing their Long Range charts a few days ago and the fact they were showing a Northerly for the beginning of December.

Got fingers crossed that something wintry will elvolve near to, or on Christmas day.

[A Winter's Tale]

40% Chance of a White Christmas for Scotland. Hopefully this year will be a third consecutive white christmas - even if it has to come from a brief NWly.

[johnholmes]

Week 12 now available to view.

Raw CFS every day for the whole winter with a summary on each day. CFS anomaly charts for each day with comments at times.

CFS for the winter with jh-issue 12-wed 23 nov 2011.doc

[November13]

I am thinking more an Aussie style barbie this year!

[Weather-history]

Looking at the latest CFS output, no sign of the deep cold of last Christmas, infact that run is unsettled throughout. There wasn't even a short period of anticyclonic weather sat over the UK.

[Stuart]

Forecast

Our fourteenth update marginally reduces the chances of Christmas snow in the north and south. The weather patterns so far during November have remained blocked, with a mild southerly flow, although a change is now taking place. It looks as though December wil l begin with a mobile set up with little sign of a nationwide cold spell. The current Christmas forecast is for mostly mild to average temperatures with winds coming from the west or south west.

Probabilities of snow falling on Christmas Day

North of Yorkshire / Lancashire: 19%

South of Yorkshire / Lancashire: 14%

Forecast issued

Update 1, 01/09/2011

Update 2, 10/09/2011

Update 3, 13/09/2011

Update 4, 17/09/2011

Update 5, 25/09/2011

Update 6, 01/10/2011

Update 7, 08/10/2011

Update 8, 16/10/2011

Update 9, 23/10/2011

Update 10, 30/10/2011

Update 11, 06/11/2011

Update 12, 13/11/2011

Update 13, 20/11/2011

Update 14, 27/11/2011

http://theweatheroutlook.com/forecast/Christmas-weather-forecast

[johnholmes]

A mainly mild

this was my summation of December using the raw CFS output from yesterday.

They do change almost every day with different forecasts of the weather through each winter month and Xmas Day just the same with its changes.

The full update with daily outlooks on both CFS raw and anomaly charts is due on Wednesday evening.

A mainly mild unsettled start to December. Colder air from the west on the 6^th with a northerly developing by the 8^th. A high moving in from the SW on the 10^th brought milder air to all round its northern flank. This dominated the weather as it edged east into the country then SE into southern Europe. A northerly developed on 18-19^th so much colder again with a high to west of the UK. It brought less cold air in at times to the western half of the country but it was only from about 24^th that milder air covered all parts. Colder air, briefly tried to return westwards from the high, by now to the east, but a succession of lows turned it milder and unsettled until New Years’ Eve when northerly winds came round the western flank of the final low.

Edited November 28, 2011 by johnholmes

[johnholmes]

and another week nearer Christmas-the usual look at raw and anomaly CFS outputs daily (when around).

This will be the last one with December data in other than the Christmas Day chart. It seems pointless as by this time next week we will be well into the first week. CFS vGFS is usually a win for GFS at that range!

Next week I'll have my own stab at a forecast for the Christmas period.

CFS for the winter with jh-issue 13-wed 30 nov 2011.pdf

Edited November 30, 2011 by johnholmes

[Stuart]

Forecast

Our fifteenth update increases the chances of Christmas snow in the north and south. Conditions during early December have turned colder, and it looks as though the anomalous mildness which persisted through much of the autumn will probably not return for long periods in the run up to Xmas. The current Christmas forecast is for unsettled weather with showers or longer spells of rain, and mostly average temperatures, although possibly cold enough in the north for some wintry conditions over higher ground.

Probabilities of snow falling on Christmas Day

North of Yorkshire / Lancashire: 24%

South of Yorkshire / Lancashire: 18%

Forecast issued

Update 1, 01/09/2011

Update 2, 10/09/2011

Update 3, 13/09/2011

Update 4, 17/09/2011

Update 5, 25/09/2011

Update 6, 01/10/2011

Update 7, 08/10/2011

Update 8, 16/10/2011

Update 9, 23/10/2011

Update 10, 30/10/2011

Update 11, 06/11/2011

Update 12, 13/11/2011

Update 13, 20/11/2011

Update 14, 27/11/2011

Update 15, 04/12/2011

http://theweatheroutlook.com/forecast/Christmas-weather-forecast

[mountain shadow]

I feel any likliehood of a white christmas will be courtesy of a northerly toppler.