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Paul

Community winter forecasts

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A thread for members of the community to post their winter forecasts for 2015/16. 

 

A wet and potentially wild start looks to be the safe bet, but where will it go from there!

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I am not sure what the weather will be like over the winter period and would really expect an average type of winter with possibly some snow and ice, some rain and wind with the occasional milder day.

 

Any prolonged spells of intense cold and snow appear to have been a rarity these days, so I am not really expecting any different but you never know your luck, a Scandy/Siberian high may establish itself and give us a period of the lovely dry snow with some nice sunny days :) Don't really like the slushy stuff, grey skies and drizzle :(

 

But what I am confident of is that until 15th December the sun will be setting earlier with the earliest time being about 15 hours 51 on that date and gradually the evenings will become lighter, yippee! - roll on Spring.

 

Strangely enough the mornings will continue to get a little darker for about a fortnight after this date.

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My preliminary thoughts on winter:

December:

Slight above temperatures; above average rainfall; very unsettled, predominately westerly winds; stormy, potentially severe; PV southern Greenland; cool beginning but becoming increasingly milder; chance of brief interludes of cold NWly/Nly or crisp settled spells.

January:

SSW early January; continuation of unsettled wet and windy conditions, close to average temperatures; becoming more settled but mild mid month; turning much colder and blocked latter half of month, breaking down before February; below average temperatures overall, slightly below average precipitation

February:

Most difficult month to forecast - messy, damp and dull beginning, becoming unsettled and potentially stormy; quieting down and return of blocking before mid month, breaking down later; quiet, mild and damp end; slightly below average temperatures, average rainfall.

In summary, December is shaping up to be quite an unsettled month, possibly disturbed with a familiar strong El Niño NH set up. Implications in the nature of temperature and weather patterns unclear but I would say a chilly beginning with plenty of wind and rain, becoming milder around days 10-20, possibly beyond possibility of short colder interludes in the latter part of the month.

Early days but there seems to be strong indications that the way this autumn has panned out so far could have interesting implications later in the winter and a SSW is more than a possibility. If an SSW does occur, the timing is up for debate but I think sometime in the first week of January. Possibly a very zonal beginning to January, temperatures difficult to predict with confidence so I'd sit in the fence and say around average. Most Becoming milder with possibly murky conditions as high pressure moves closer to the UK about 10 days. I'm confident a period of sustained blocking will occur in the second half of January with heights centred to the north/north East. I think a messy breakdown would occur by the end of the month with plenty of murky conditions as the Atlantic makes a return.

February is always the difficult month to forecast as it is the furtherest away but the conditions or weather patterns are more difficult to describe. I think an initially quiet, transitional spell of weather to begin with then becoming unsettled with more active Atlantic dominated weather for a time. Before mid month a return of HLB, this time to the NW and breaking down at the end of the month and replaced by a quiet, mild transition to Spring.

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My preliminary thoughts on winter:

December:

Slight above temperatures; above average rainfall; very unsettled, predominately westerly winds; stormy, potentially severe; PV southern Greenland; cool beginning but becoming increasingly milder; chance of brief interludes of cold NWly/Nly or crisp settled spells.

January:

SSW early January; continuation of unsettled wet and windy conditions, close to average temperatures; becoming more settled but mild mid month; turning much colder and blocked latter half of month, breaking down before February; below average temperatures overall, slightly below average precipitation

February:

Most difficult month to forecast - messy, damp and dull beginning, becoming unsettled and potentially stormy; quieting down and return of blocking before mid month, breaking down later; quiet, mild and damp end; slightly below average temperatures, average rainfall.

In summary, December is shaping up to be quite an unsettled month, possibly disturbed with a familiar strong El Niño NH set up. Implications in the nature of temperature and weather patterns unclear but I would say a chilly beginning with plenty of wind and rain, becoming milder around days 10-20, possibly beyond possibility of short colder interludes in the latter part of the month.

Early days but there seems to be strong indications that the way this autumn has panned out so far could have interesting implications later in the winter and a SSW is more than a possibility. If an SSW does occur, the timing is up for debate but I think sometime in the first week of January. Possibly a very zonal beginning to January, temperatures difficult to predict with confidence so I'd sit in the fence and say around average. Most Becoming milder with possibly murky conditions as high pressure moves closer to the UK about 10 days. I'm confident a period of sustained blocking will occur in the second half of January with heights centred to the north/north East. I think a messy breakdown would occur by the end of the month with plenty of murky conditions as the Atlantic makes a return.

February is always the difficult month to forecast as it is the furtherest away but the conditions or weather patterns are more difficult to describe. I think an initially quiet, transitional spell of weather to begin with then becoming unsettled with more active Atlantic dominated weather for a time. Before mid month a return of HLB, this time to the NW and breaking down at the end of the month and replaced by a quiet, mild transition to Spring.

 

 

Quite a mixed winter then...

 

SSW's increase the chance of sustained blocked cold conditions lasting some time - so not too sure about your Feb forecast, but we shall see.

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A simple one from me.

 

North/South split.

 

Cold/snowy North at times; wet, less cold South.

 

PM incursions a frequent occurence this Winter with varying consequences.

 

I dont see any prolonged Wintry spell, aka 10 days plus, in nature.

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Winters 85-86, 90-91, 95-96, 00-01, 05-06, 10-11. None of these winters were mild,perhaps one or two were around average at worst. Taking this sequance on its own the next winter is 15-16.

Many of our best spells at least in my location regarding cold have come in these winters since the mid 80s. I think perhaps for whatever reason its a bit more then just a coincidence. One quirk about these winters was the most potent cold spells and snaps during them came in december and/or february. Feb 86,feb 91,dec 95,potent cold snap end of dec 2000,cold spell end of feb into early march 2001,short sharp snap end of dec 2005,cold spell end of feb into early march 2006 and of course dec 2010.

So not very scientific but based on that I will have a go at a forecast for winter 2015-16.

First half of December well it does look like It will be often unsettled with bouts of Pm air and some milder days,fairly average fare for the time of yr but temps a bit below average overall I would think.

3rd week of december and into the run up to xmas it will turn milder i think and becoming that more settled as the Azores Hp becomes more of an influence.

Last week of the month a sharp cold snap will hit as air comes down from the arctic giving snow in places. Courtesy of some heights around Greenland.

First few days of jan may start cold but I think the pv will ramp up and the first half of the month will overalll be very zonal with temps above average.

Second half of the month it will turn dryer and a little cooler with average temps ,but nothing this month to be interested in if you are a cold lover.

Continuing to cool down however during the first half of Feb with temps a little below average and some dry and frosty weather about.

Second half of the month will be bitter,the coldest period of the winter with very cold air moving west from eastern europe,snow for many.

EDIT:

For what its worth here are some composites I made on the winters I mentioned.post-6445-0-54859900-1448357031_thumb.pnpost-6445-0-53166100-1448357048_thumb.pnpost-6445-0-49166900-1448357063_thumb.pn

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Statistically speaking ...

 

Compared to Jan to Oct 2015, the years 1972, 1863, 1738, 1957, and 1894 are the closest five, in descending order. This is not a measure of temperature but rather the pattern of the anomaly against the 1984-2014 average. Here's the data:

 

post-5986-0-87969500-1448260097_thumb.pn

 

The average extrapolated for November comes in at -0.33, so close to normal. I don't know what this years November CET will be, but looking at the data on the analogues shows no real pattern, so a throw away value. Based solely on this it could've been warm or cold. However, extracting the averages and graphing shows a different story. Here's the chart:

 

post-5986-0-17327900-1448260277_thumb.pn

 

Note the average comes in slightly cooler than 2015 but we'll leave comments on that for a different much scarier thread. You can see that the average does follow this years weather pattern quite nicely (which is exactly what we'd expect to be honest: I used Pearson for the pattern matching, if you're at all interested)  Here's the prediction from this method:

 

post-5986-0-58111300-1448260393.png

 

So going for a warm end to year, followed by cold in the later two months of winter. Not much between Jan and Feb, just cold - and quite significantly, too. If November does turn out to post a significantly high anomaly, then 1894 is the closest. Look at the data above - OMG, snowmaggedon, or, more likely, very cold, high heating bills, and clear blue skies. Hrumph. Much more likely that 1863 is a better analogue, and even that shows cold ...

 

Better than observing squirrels digging up my lawn and playing with their nuts, I guess, but no idea how much better! I could figure it out, but where's the fun it that  .... incidentally, 1972, and 1957 both were strong El Nino years - no idea about the stuff centuries ago.

 

EDIT: Got December's prediction wrong (I used the November average) here's the whole lot, corrected.

 

post-5986-0-44807000-1448261819_thumb.pn

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Now, from the analysis above, if you were to pick all of the closest years that occurred on or after 1948, they came out, in descending order 1972, 1957, 2007, 1968, and 1993. Here's what the composite reanalysis looks like,

 

post-5986-0-27576700-1448264408_thumb.pn

 

Here's the same one zoomed in for Europe,

 

post-5986-0-56777600-1448264644_thumb.pn

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Here's the anomaly charts for the winter, from the analysis above,

 

post-5986-0-92857000-1448264911_thumb.pnpost-5986-0-71216000-1448264917_thumb.pnpost-5986-0-81044600-1448264924_thumb.pn

 

The end of civilization as we know it in February, then ...

 

:cold:  :cold: :cold:  :cold:  

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If we think that, say, the November CET will be 9degC, then that changes everything.

 

The analogue years become 1994,1894,1661,1938, and 1863. Here's data and chart,

 

post-5986-0-89151600-1448269856_thumb.pn

 

Interestingly, 1894 appears on both analysis.

 

The since 1948 analogue years become 1994, 2009, 2011, 1954, 1972. Here's the composite reanalysis,

 

post-5986-0-25468200-1448269903_thumb.pnpost-5986-0-30156600-1448269909_thumb.pnpost-5986-0-93730200-1448269915_thumb.pn

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I know what you're all thinking. Lies and statistics ... how would it have done last year? Well, wait no longer, here it is:

 

The analogue years are 1715,1725,1920,2011,1661

 

post-5986-0-32141300-1448272558_thumb.pn

 

The post 1948 years are 2007,1961,1999,1977,1972, here's their composite reanalysis, and what actually happened:

 

post-5986-0-40261700-1448272965_thumb.pnpost-5986-0-66383900-1448272974_thumb.pnpost-5986-0-38049900-1448272981_thumb.pn

post-5986-0-17725900-1448272986_thumb.pnpost-5986-0-22864900-1448272996_thumb.pnpost-5986-0-32668500-1448273002_thumb.pn

 

So, using post 1948 years only the results are truly terrible.

 

It does get the pattern correct using the whole CET series, though, even though for an actual prediction, we'd need to adjust it, but not quite sure how. I think about best this method can do is suggest whether or not the anomaly is likely to be above average or below - not sure it can even do that.

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My mini area of interest right now is on the effect of SSTs on PM shots. I was interested to see that this weekends front, sourced pretty much in a straight line from Newfoundland, arrives over mainland England/Wales at -6C at 850Hpa. I wish I had time to look into this more, but I just feel this is what I would expect from a PM burst in early February, not late November. Once we get to -7C or -8C from Atlantic sourced air , then I would have thought lowland snow becomes a possibility. So if the cold SSTs are affecting the moderating influence of the Atlantic, and if as one would expect, they get even colder over the next two months, is there a possibility of a major snow event straight off the Atlantic, come January/February??

So sorry, no long range forecast from me due to lack of time, but rather a thought that perhaps our "normal" weather could see an abnormal result!

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I would like to join the congratulations for a well assembled winter report.
I hope there is room on the forum for a second opinion.

First let's look at the hype about this 2015/16 El Nino, and about it being the strongest ever in recorded history   
http://www.radionz.co.nz/news/world/283038/strongest-ever-el-nino-headed-for-nz

which is an extremely bold claim, seeing that Peruvian recorded history of these events dates back 15,000 years 
http://www.latinamericanstudies.org/ancient/nino.htm

But then some mets came out saying it is the strongest only since 1997 
http://www.theage.com.au/business/mining-and-resources/farmers-forced-to-slaughter-cows-as-el-nino-leaves-no-room-for-passengers-20151023-gkgm2x.html

and then even this got drastically modified
http://www.weatherzone.com.au/news/bureau-of-meteorology-says-el-nino-on-its-way-out-widespread-rain-on-the-way-in/398164  

So in going from strongest-ever to almost-gone within 2 months, I do think there is fair justification to challenge the process used to jump to these quickly changing conclusions.
Firstly, because comprehensive satellite data goes back only to 1979, it would be impossible to call any El Nino the worst or strongest 'ever' in modern times.  Secondly El Nino was only named as such in 1982-83, previously called the southern oscillation index (SOI) and then Humboldt Current, and most have forgotten 1965-66 which would be the most destructive El Nino-type condition so far, worldwide. Thirdly, El Nino only ever historically referred to Australia and the variance between SSTs between Tahiti and Darwin, which is how it is still monitored to this day.

 

Solar connection factors 
1.  We have just come through solar cycle#24 which peaked at the end of 2014 and cycle#24 is now in decline. 
2.  El Ninos typically follow solar cycle peaks and minimums. There are roughly 2 El Ninos per decade.
3. The strength or weakness of the solar cycle just before El Nino determines the strength or weakness of the El Nino. 
4.  We have just come through a weak solar cycle - logical outcome: a weak El Nino. 
5.  Weak El Ninos after weak solar cycles have been 1976-78 and 2006-7. 
6.  Strong El Ninos after steep solar cycles have been 1957-58, 1965-66, 1982-83, and 1997-98.
7.  El Ninos reduce cyclones.  A weak El Nino will reduce number and strength of cyclones. El Nino-equivalent years also slow the Gulf Stream. A weak El Nino will slow it only a little.

 

No such thing as an El Nino winter in the northern hemisphere
Science is an exercise that uses language in an approach towards precision. Unfortunately weather is an inexact science, which means it hardly qualifies to be a science at all, and is closer to beinh just a set of informed opinions, which places it nearer to journalism. Neither is there any such thing as an El Nino summer in the southern hemisphere. Due to the solar and lunar cycle of seasons this coming southern hemisphere summer will be long and dry, but that is not what is meant by El Nino, which refers more to the Australian dry season between autumn and spring. El Nino is not a description that applies in summer. The 2015-16 El Nino will be chased away by a spring La Nina around next October and November for Australia. A 'northern hemisphere El Nino' is just a desire to get in on the media excitement. In these days of global warming/climate change hype, El Nino has been added as another fearmongering factor for climatologists to attract research funding from gullible governments and the even more gullible taxpaying public.

 

Ireland winter
As I have been saying all through this year through my website www.predictweather.com and in my Weather Almanac for Ireland for 2016, I estimate that the coming Ireland winter should be fairly mild, with a storm in the first week of January and snow mostly in January and March, with the last snow day likely in May.  Winter is close to being typical for Ireland. Conditions will not be too severe, but with the usual occasional rain and snow. The windiest spell may be in the third week of February.  
The Sun determines the temperature cycle, not the El Ninos, which are part of a lunar cycle of changing ocean current directions. Sometimes in El Nino westerly winds strengthen and direct Atlantic storms on a northerly track across N Europe dragging the jetstream south and over eastern Europe which can mostly miss Ireland.  Of course temperatures will drop in coming weeks, but that is the nature of seasonal change. 
Perhaps the hype about strong El Ninos bringing harsh winters to Ireland is also misinformed.  1982-83 and 1997-98 were strong El Nino years but there were no harsh UK winters then. Even if we allow this winter to be labelled El Nino-like, I would estimate it to be another weak El Nino year. The weak El Niño winter of 2006/2007 was unusually mild in Europe, and the Alps recorded very little snow coverage that season. As forementioned, El Niños typically follow a solar maximum or minimum and we have just come through a weak solar cycle  e.g. the weak El Nino of 2006-7 followed a weak solar cycle.  Alternatively, strong El Ninos follow relatively steep solar cycles e.g. the El Ninos of 1957-58, 1965-66, 1982-83, and 1997-98.   
During the last El Nino of 2009/2010, winter across northern Europe, including Ireland was very cold mainly because there was a deep, long, solar minimum at the same time and basically the sun was asleep.  The same happened during the extended solar minimum of 1962-62, still called one of the coldest winters Ireland has ever had.  A further example was the extended solar minimum during 1932-35.  What happened then? In 1932 the Niagara Falls froze over. In 1933 came the Great Blizzard of February 1933 which was the greatest weather event of the 1930s to struck Ireland, and at the time was reported as being the greatest weather event of the 20th century. Therefore El Ninos must be considered along with depth of the solar cycles they follow. 
Looking ahead, I would suggest that like November, December is again drier, sunnier and warmer than average. There may be fluctuating temperatures with rain in the first and third weeks and a temperature drop around 12-16 December. A frost is likely just before Xmas Day, then on 26 December come cold SE winds followed by wintry rain as temperatures barely climb above freezing.  Therefore expect snow on or near 12 and 28 December.  
January is unsettled in the first half of the month but fairly mild, with stormy rain 9-19 January.  On several occasions temperatures will climb to nearly 15C  and this may feel warm and spring like.  This has happened several times before so  is not global warming, and even though daffodils may start to flower it is just in response to soil temperatures. Chances of snow come around 17 January.  
February is again interesting as regards daytime temperatures.  After 12 February, winds from the south draw warm air up to possibly around 14-15C.  Then it goes windy between 17-26 February and snow is a possibility around 17 February. The month is mostly cloudy.   March is a month of mild temperatures, with about 2/3 of daytime maximums reaching to above 10C, only dipping below 2C on about three days.  Conditions will be good for snow around 3, 10 and 14 March.
April is much colder than the winter months in the last week, with possibility of snow around 18 and 23 April. In the last week in April comes the first decent spell of sunshine.  I would say don't get your hopes too high - summer will be cool and unsettled overall, with some good dry intervals but no prolonged heat waves.
Ken Ring

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How, Ken, are El Ninos part of the lunar cycle? What has the moon got to do with warming the Pacific Ocean?

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Ed, the SOI, from which El Nino was but a media-inspired offshoot, is a function of the lunar declination cycle.

Basically, due to the earth's obliquity, the moon changes (earth) hemispheres on a 27.3 day cycle. This moves huge volumes of water back and forth and correspondingly the changing of barometric pressures. All weather comes from the ocean and most rain ascends from it, with most rain falling back into the sea. Most violent storms are never witnessed by humans. Deep currents produce swells which become surface waves, then SSTs, winds, then varying air pressures. Storms at sea do not come from far off - they originate under your boat. No one ever reported sailing on a calm sea whilst a violent storm raged down from the sky above.

Currents are a lunar consequence, starting first with the transiting moon's daily jostling of the earth's inner core. This is the ball at the centre of the earth's geomagnetic electrical field, which sits at the earth's centre. The transiting moon becomes electrically charged as it passes through earth's outer electrical field. There are then two magnets attracting each other: the moon and the inner core. The moon releases pressure because it is perpetually transiting, but the inner core exerts pressure on adjacent earth and in the direction of the moon, resulting in the daily Land (or Earth) Tide. As a result, up to two thousand kms of vertical displacement of the earth rises and falls every day at every point of the earth's surface, the bulge following the transiting moon. Australia rises and falls 50cm, the equator by about 55cm and NZ and Ireland about 20cm.

The Land tide governs what happens in the ocean, which only averages 2-3kms in depth if shared over the area of the oceans. The currents are a cyclic function of this land displacement, originating from the behaviour of the moon. Otherwise one would have to ask, knowing the existence of the Land Tide, and how the earth bulge follows the moon, how could this 'tide' in the surface of the crust not be traceable to lunar positions? knowing there is a land Tide, and the tiny amount of sea compared to depth of land beneath, how is the coastal tide not answerable to the land displacement?

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Not being funny but the moon making the sea go up and down, back and forth on a regular basis isn't the same as vast ocean currents changing dramatically in temperature. The moon has a regular and predictable pattern, the sun, no matter how active or inactive doesn't change the orbit or gravitational pull of the moon. So, if the sun doesn't change the moon and the moon doesn't behave in an erratic manner, how can either one, or both combined, possibly cause an El Nino?

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You may have already read my winter forecast in the seasonal forecast thread which remains in the weather discussion forum (as opposed to this winter discussion forum).

 

Basically, with some collaboration with Blast from the Past, we expect December to become stormy at some point around the middle to end of the month in particular, there may be variable spells of very mild and near normal or even slightly below normal temperatures but the average is likely to be 1.5 to 3 deg above normal in my opinion (Fred may be closer to near normal).

 

January is likely to become more variable as some European blocking develops and really, the only major difference between our outlook and the NW forecast seems to be that we look for the coldest period to come more like end of January into February. Some period will be below normal but it may not neatly overlap the calendar months, so for those we're expecting just slightly below normal values in both months, however if there is to be a 30-day period that is considerably colder I would expect it to be something like 12 Jan to 10 Feb approximately. So this is when snowfall would be most likely this coming winter.

 

I have looked into cause and effect of El Nino and my findings are a lot different from what was posted earlier. I agree that lunar declination has an effect on ocean currents and may play a role in at least a statistical background sense in the timing of El Nino events. I've noticed that they are more likely to occur around times when the northern declination maximum is at or just after lunar perigee, a factor which would tend to pull water north in relative terms (against the background of daily tidal cycles and weather-event related fluctuations, this can be hard to see in data unless you take long-term statistical averages). However, I don't see much correlation with solar cycles except that strong El Nino events probably occur more frequently in active solar periods. I think there's a third external cause in the solar system magnetic field which is perhaps more directly working on the Pacific oscillation, but I'm not in a position to explain further at this time as it is developmental research (that is quite promising, I have an in-house model that correlates at a very good rate with the SOI based on solar system dynamics).

 

Jethro was probably on the right track with her question, because while the Sun obviously drives our thermal cycles and the Moon interacts strongly with the oceans, they tend to do so in annual and monthly cycles that do not change as much in relative terms as some other external signals. So I find it more profitable to look there since higher variability of signal (even if strength may be weaker) will perhaps be a more significant driver.

 

As to whether this is a strong or weak El Nino, water temperature patterns appear strong to me, but so far I have not seen quite as strong a response in the mid-latitude atmospheric waves as we saw in either 1982-83 or 1997-98. The patterns are somewhat similar this winter, but less dramatic. In early Dec 1982 temperatures in eastern North America were at all time record highs, I remember it being very close to 21 C in southern Ontario around the 2nd and 3rd. Recent mild spells have been more like 10-12 C compared to normals of 6-8 C. There were also some very high daily temperatures in the 1997-98 El Nino across North America. This may still come about in 2015-16 but so far it has been more of a muted response like a 1925-26 or maybe 1972-73 type.

 

My data analysis shows that an El Nino winter in Britain (from the CET) will likely feature blocking around mid to late January but otherwise mostly zonal and rather mild patterns. A strong European high often shows up around mid to late January but some cases you would assess it as being unconnected to the SIberian high, not particularly cold other than its inversion creating properties. Other El Nino winters manage to get a bit of Siberian air west but it's not the best phase of the SO for that to happen.

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Cheers Roger, wondered if I was missing something glaringly obvious as it just didn't make sense to me.

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I may have posted this before, but this is our very own forecast which both me and my friend have writ out and put together ourselves, so here is our winter forecast from the Isle of Wight Weather Community

 

Winter forecast 2015/2016 (December, January and February)

This years forecast is somewhat more confusing than previous years due to conflicting signals.
If you only want to read about the forecast then please scroll down to the bottom of the article but if you want to read about how we put the forecast together then read on!

Producing a winter forecast is extremely difficult, mainly because small scale events (such as an unexpected cluster of thunderstorms over the Azores for example) can lead to a complete change of weather for us in the UK, so whilst we like to try and forecast a general trend, a specific forecast is completely impossible, even with today's level of technology.

So how do we put this forecast together?

We use a whole array of different computer models and forecast models and this combined with real-time data of wind strength and directions from various atmospheric altitudes and latitudes.

Quasi-biennial oscillation
The QBO is a fairly useful tool in predicting the season ahead, especially later in the winter. The QBO is the measurement of wind strength and direction in the upper atmosphere close to the equator. The wind in this area goes through phases, sometimes blowing eastwards, sometimes blowing westwards and this can have a butterfly effect which can impact the weather for the UK.
Currently we are in a westward phase of the QBO which evidence shows can have an effect on.........

Stratospheric Warming
Sudden Stratospheric Warming or an SST can develop at any time during the winter months but more especially later in the winter.
It happens when the upper atmosphere suddenly starts to warm at an unprecedented rate, sometimes rising over 100C in just a few days! This disrupts the normal anticlockwise motion of the upper level winds and this can often propagate downwards which in turn can have an effect of disrupting the usual west to east jet stream wind pattern of the troposphere (the area where all the weather takes place). In turn this can cause the jet stream to meander north and south rather than moving west to east which then causes colder air to drift south into mid latitudes (including the UK).
Now this is the difficult part! Stratospheric warming's take place quite often when the QBO is in a westerly phase BUT this happens more often when the sunspot activity is high. Currently the sunspot activity is very low and this may lessen the chances of a SST developing.

Sunspot activity
As mentioned above the activity of the sun can have an influence on atmospheric weather patterns. We have just talked about how the sun and the QBO go hand in hand with producing warming's in the upper atmosphere but there is another side to the story (a conflicting side).
During high sunspot activity it is often seen that the Jet stream increases in strength which in turn brings nasty conditions such as wind and rain to many places in western Europe whilst a long period of low sunspot activity can lessen the effect of the jet stream over a longer period of time. This contradicts everything we have said above but there is a reason behind it. When the QBO is neutral or in an easterly phase and the sunspot activity is very low it may lead to a general period of cold and once established my last the whole winter whereas a westerly QBO phase (as now) with low sunspot activity often sees the coldest conditions later in winter such as February and March as this is when the highest chance for a SSW may occur.

El Nino Southern oscillation (ENSO)
I expect you have all heard in the news that there is currently a very strong El Nino taking place. An El Nino is the warm phase of ENSO whereas a La Nina is the cold phase.
The warm phase is when the central or eastern tropical pacific ocean warms dramatically and this of course can have a large impact on global weather conditions.
A La Nina is when upwelling cold water starts to cool the surface temperature in the central and eastern pacific ocean.
In the UK during a strong El Nino we often see high pressure developing towards central and northern Europe and this often brings a dry winter season in those areas including the UK. As well as a dry winter season it is often slightly milder than average as a whole, especially early on in the season during the mid/late autumn and often again mid winter.
This year however we have a few conflicting signals which means that although El Nino is likely to have some of the usual effects (drier than average for the UK) the conflicting signals may not keep things quite as mild as the winter develops.

Cold pool in the mid Atlantic
This is something else that has often been mentioned in the news in recent weeks.
A colder than average Atlantic usually has the effect of producing somewhat weaker storm systems due to a slightly weaker Atlantic jet stream and this often means that the low pressure storm systems will either stall out to the west of the UK or reach us in a rather weakened state. Also if High pressure manages to set up to our east it will mean that any rainfall will be deflected as the low pressure systems attempt to move northeastwards around the blocking high pressure area. This also means we may occasionally see a stronger than average Azores high pressure system, especially later in the winter although it is likely to be displaced slightly further south than usual.

North Atlantic oscillation
The "NAO" is the pressure pattern of the north Atlantic.
When it's in a negative phase it means that pressure is higher than usual in high latitudes.
When in a positive phase it means that low pressure is more frequent in mid and high latitudes.
This winter we think that it will be rather neutral overall with a slightly positive anomaly in December and January. We are expecting there to be a somewhat negative anomaly in February and March.
Other data
There are a few other things we take into consideration, one of which is the European pressure patterns during October. Using October as a winter guideline isn't an officially validated method but by using certain markers throughout the 40 days from the end of September thought to the start of November we have found a near 75% correlation between those patterns and the period December, January and February.
The main part of this method is the persistence of a European high pressure cell throughout October.

UK winter forecast 2015/2016

The coming December is a very difficult one to predict due to the mixed signals but current indications point to a fairly average month temperature wise with the potential of one or two cold spells.
We think that any cold weather is most likely at the start of the month and again later in the month. We aren't expecting any long duration cold spells but we think there may be a few fairly strong Atlantic storms, especially mid month, also any cold that develops later in the month may be quite intense although of rather short duration.
Temperature slightly below average
Rainfall slightly below average

January is looking like a rather mixed month with a rather chilly start but also signs of a dry mild period mid (possibly around mid month). Later in the month things may turn colder once again.
A few Atlantic storms are also likely although we aren't expecting severe conditions like previous years.
Any cold spells are likely to be very short lived but possibly quite intense and we certainly wont rule out the odd snowfall although predicting snow at this range is virtually impossible.
Temperature close to average
Rainfall slightly below average

February looks as though it could be rather chilly with a mix of cold dry spells interspersed with wetter slightly milder conditions.
We are expecting a handful of colder periods more especially towards the end of the month.
Temperature below average
Rainfall close to average

Please remember that forecasting a whole season ahead with accuracy is impossible so instead we try to pick up on trends. An educated guess-cast is probably a more accurate way to describe it although there is a fair amount of science behind our predictions and our forecasts have proven to be rather effective with a very high accuracy rating for the 2013/2014 winter of storms and an extremely high accuracy rating for the 2010/2011 winter.

Forecast put together by Jamie Russell and Ryan Trigg of IOWW.

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Not sure why there is so much silence this year it seems.. hardly any members are posting winter forecasts. Do people think it is a done deal or something?

 

Anyhow here is mine for what its worth (based on reading other forecasts and looking at signals and the expected influence of El Nino state and its effects on te stratosphere).

 

Overall - A very mixed winter, with a bit of everything, temps averaging out close to average but masking some potential wild extremes..

 

December - Generally a mild and wet month for many, fairly dry in the SE though, and a bit colder than normal in Scotland and N Ireland.

Starting off very unsettled with bouts of rain from the NW, always the wettest windiest weather reserved for the NW, tropical maritime air for much of the country away from the far north, so mild or very mild for most with little frost. Likely to turn settled in the SE as we move through the second week with high pressure influencing things here, but probably unsettled still for Scotland, N Ireland and N Eng, with further rain but also some colder polar air at times thanks to low pressure moving close to Scotland. Second half of the month, perhaps a continuation of the same theme, high pressure close to SE England but perhaps pulling in a slightly colder continental theme bringing some frost, the north stuck under alternating polar maritime and tropical maritime frontal action. End of the month could see a marked change as the high over the near continent begins to ridge northwards to Scandinavia.

 

January - I'm going with what a few forecasts are suggesting and that is a marked warming of the stratosphere enabling a displacement or split in the Polar Vortex, which by now will have firmly reached its winter peak (earlier than usual). Perhaps starting off with a bit of an atlantic /continent battleground, conversely very mild with southerly winds, however, as we approach the middle of the month, anticylonic conditions win out with strong height development to the NE quickly and the jet is forced on a southerly path. The rest of the month sees northerly/easterly airstream.

 

Feb - A cold month overall but perhaps quite a dry one with anticylonic conditions prevailing for much of the time.

 

If we don't see the stratosphere behaving in such a way to cause a marked cold spell second half of the winter, I don't necessarily foresee a zonal dominated winter, instead perhaps a benign second half with mid atlantic heights/azores high and weak atlantic attacks on occasion, with quite seasonal weather overall, but nothing extreme on the snowfall or cold front, nor silly mild (I'm going against the Net Weather forecast).

 

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