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Winter 2018/2019 - General Discussion

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  • Registered Users Posts: 1,003 ✭✭✭Lucreto


    image.jpg

    So it begins

    Edmonton, AB Canada


  • Registered Users Posts: 13,477 ✭✭✭✭sryanbruen


    UK Met Office Glosea5 September 2018 update for Winter 2018-19 has an above average chance of verifying if you ask me.

    Why do I say this?

    - The Atlantic SST profile favours it
    - QBO will go westerly

    It'd be a mild and wet scenario.

    The Atlantic SST profile is really the main reason why I don't have much faith in this Winter being "the one" of this incoming solar minimum. It has changed very little since I last updated on it here.

    If there's two things I'd say in regards to the QBO going westerly, the early Winter will likely not have much impact from it going westerly as there's a time lag and the expected weak Polar Vortex for November/December could have a say in things too. We shall see.

    GD9711q.png


  • Registered Users Posts: 13,477 ✭✭✭✭sryanbruen


    I see the above post wasn't the news you wanted :p, well remember it's only based on two things; Atlantic SSTs and QBO. I'm gonna further the discussion here on the QBO. Many other things to consider!

    My graph I generated below shows the QBO for every Winter back to 1949-50 up to 2017-18 (y-axis) along with the Central England Temperature for each of the Winters (x-axis). We can see colder Winters (the Winter average is 4.5c) tend to occur relatively more during easterly QBO years than westerly QBO years especially if it's very/extremely cold levels such as 1962-63 or 2009-10. Not impossible to get a severe Winter in westerly QBO, one in particular there stands out like a sore thumb; 1978-79 which contained the last subzero January for the CET and the last New Year blizzard we have had. 1978-79 was very weak westerly QBO though so explains that.

    The QBO is something we can predict somewhat like it's nearly guaranteed to become westerly by New Year (or even late 2018) but it's difficult to predict strength and exact timing of transitions to phases. All the QBO is an index that reflects the strength of the zonal winds in the stratosphere and during easterly QBO phases, it is easier for SSW events to take place but it is not impossible for them to occur in westerly QBOs.

    Late 2010 (November/December 2010) was during a westerly QBO phase (and fairly strong at that) but other factors such as the sun's magnetic field, Iceland volcano, warming over Canada and low speed of the gulf stream, fend off the westerly QBO phase influence until later in the Winter. The QBO is one reason why people are feeling a front loaded Winter is going to take place this year with the coldest conditions either in December or January like 2010-11, 1996-97 and 1981-82.

    Enyj14d.png


  • Registered Users Posts: 742 ✭✭✭Cork981


    sryanbruen wrote: »
    I see the above post wasn't the news you wanted :p, well remember it's only based on two things; Atlantic SSTs and QBO. I'm gonna further the discussion here on the QBO. Many other things to consider!

    My graph I generated below shows the QBO for every Winter back to 1949-50 up to 2017-18 (y-axis) along with the Central England Temperature for each of the Winters (x-axis). We can see colder Winters (the Winter average is 4.5c) tend to occur relatively more during easterly QBO years than westerly QBO years especially if it's very/extremely cold levels such as 1962-63 or 2009-10. Not impossible to get a severe Winter in westerly QBO, one in particular there stands out like a sore thumb; 1978-79 which contained the last subzero January for the CET and the last New Year blizzard we have had. 1978-79 was very weak westerly QBO though so explains that.

    The QBO is something we can predict somewhat like it's nearly guaranteed to become westerly by New Year (or even late 2018) but it's difficult to predict strength and exact timing of transitions to phases. All the QBO is an index that reflects the strength of the zonal winds in the stratosphere and during easterly QBO phases, it is easier for SSW events to take place but it is not impossible for them to occur in westerly QBOs.

    Late 2010 (November/December 2010) was during a westerly QBO phase (and fairly strong at that) but other factors such as the sun's magnetic field, Iceland volcano, warming over Canada and low speed of the gulf stream, fend off the westerly QBO phase influence until later in the Winter. The QBO is one reason why people are feeling a front loaded Winter is going to take place this year with the coldest conditions either in December or January like 2010-11, 1996-97 and 1981-82.

    Enyj14d.png

    I’ll ignore your first post and start prepping for a harsh winter now :)

    But in all honestly while your posts are not always what I want to hear (temporary Ice age event) they are very informative and interesting and I do appreciate the effort you put into dumming it down for some of us.


  • Registered Users Posts: 1,976 ✭✭✭Artane2002


    The September update from the Glosea is painful, we're so close to being under the influence of the HP to our northeast but too far away. Imagine if it shifted west sufficiently and the below average heights went down south a bit. Really it's not that far off a cold scenario. It's nice to see objective posts though rather than being biased towards one side.


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  • Registered Users Posts: 1,976 ✭✭✭Artane2002


    The JMA ensemble mean is hinting at plenty of blocking for the coming winter too but I don't think anything can beat the ECM. It looks a bit risky though.


  • Registered Users Posts: 13,477 ✭✭✭✭sryanbruen


    Artane2002 wrote: »
    The JMA ensemble mean is hinting at plenty of blocking for the coming winter too but I don't think anything can beat the ECM. It looks a bit risky though.

    People have been saying the JMA is similar in vein to the ECM for Winter 2018-19 showing a lot of northern blocking. Yes it does show a lot of it but not in the ideal spots for delivering cold to the UK & Ireland! Looks like a knife edge between a 2009-10 and or a 2013-14. Closer to a 2013-14 type scenario of all the cold being delivered to North America. Not what we want to see!

    iQIj1Pa.png

    If there's going to be cold on both sides of the Atlantic like 2009-10, this is the kind of chart required. It's similar but there are a few factors that made 2009-10 what it was.

    LUl17ou.png


  • Registered Users Posts: 13,477 ✭✭✭✭sryanbruen


    This chart from the GFS today would be a possible scenario in Winter 2018-19 given the Atlantic sea surface temperatures (there's nearly ways around it all the time to get cold, just less likely - it's always probability when it comes to weather). Notice there is still low pressure over Greenland and an Azores High; but a strong Scandi High sending in easterlies.

    M5i6sQP.png


  • Registered Users Posts: 23,370 ✭✭✭✭Kermit.de.frog


    giphy.gif


  • Registered Users Posts: 13,477 ✭✭✭✭sryanbruen


    I think it's time to really begin the analogues on here for Winter. If you'd like to see my first one which I gave due to interest, it can be found here in the Summer discussion thread and it was on Winters following on from warm Junes: https://www.boards.ie/vbulletin/showpost.php?p=107429714&postcount=964

    The signals are still there for an El Niño Modoki event to occur during 2018-19 according to numerical predictions. Therefore, this analogue will be on Winters during past El Niño Modokis.

    If you did not know what a classic El Niño is, it's when warming occurs in the eastern part of the equatorial Pacific i.e. El Niño Southern Oscillation (ENSO) regions 1+2. The below diagram shows you the ENSO regions of the equatorial Pacific. The warming has to involve sea surface temperature anomalies of at least +0.5°C above average over five tri-monthly periods (an example of a tri-monthly period being Jan-Feb-Mar).

    df4d06_c7131fcb168d4b69a62b1d1849889c14~mv2.webp

    Most of the time, this warming occurs in ENSO regions 1+2 but sometimes, you can have another type of El Niño. This type of El Niño is a "central based" El Niño or in Japanese, El Niño Modoki. With this type of El Niño, the warming is focused on the central part of the Equatorial Pacific i.e. ENSO region 3.4 (see diagram above). The diagram below compares the circulation of the classic El Niño and El Niño Modoki.

    df4d06_943d5260667c4deb808da5c777e0b917~mv2.webp

    The 500mb height reanalysis from NOAA of El Niño Modoki Winters shows an area of above average heights just to the north and west of the UK into Scandinavia and ridging over us with below average heights to the southeast of Europe. There looks to be some sort of easterly flow but not a severe one at that and just really anticyclonic. The way the high is aligned suggests that there would be a lot of frosty conditions but perhaps not much snow as the pressure is high.

    df4d06_669bc218dc3e40868ba52350352dbf28~mv2.png

    Following on from the warm Junes analogue, 2009/10, 2004/05 and 1992/93 have appeared again. If you do not know how analogues work, I pick a topic like warm Junes and look at the seasons that followed them or took place during the event. At the end of the analogue season, I bring them all together and put the most common years that appeared in the analogues into one overall analogue for the season and each individual month. For a year to qualify in this category, it must at least appear in 5 of the analogues. These years; 2009/10, 2004/05 and 1992/93, are the most common years to appear in the analogues so far but as we go over more analogues, maybe these will change and become less common or vice versa. Stay tuned for our long season of analogues. I will say that El Niño Modoki combined with other factors like low solar activity make for an epic combination for cold Winters.


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  • Registered Users Posts: 1,976 ✭✭✭Artane2002


    What the CFS is currently showing for December is perfectly reasonable. It shows lots of blocking in Scandinavia and Greenland (+ a dead Canadian PV) but a deep trough in the Atlantic. Unfortunately this drags up a mild southerly and it looks like a wet month. (January and February are much better, especially January).

    12_2018_00z_500.png?cb

    01_2019_00z_500.png?cb


  • Registered Users Posts: 32,634 ✭✭✭✭Graces7


    winter will be hard pressed to equal or exceed the ravages of early autumn... does that follow/ make sense? one extreme season leading to another?


  • Registered Users Posts: 13,477 ✭✭✭✭sryanbruen


    CFSv2 still going for the weak Polar Vortex through Autumn and December.

    https://twitter.com/WorldClimateSvc/status/1042462278841454592


  • Registered Users Posts: 16,551 ✭✭✭✭nacho libre


    sryanbruen wrote: »
    CFSv2 still going for the weak Polar Vortex through Autumn and December.

    https://twitter.com/WorldClimateSvc/status/1042462278841454592

    Is that due to the lag effect of the QBO switching from a east to west state as we go into winter?


  • Registered Users Posts: 7,796 ✭✭✭Calibos


    Lucreto wrote: »
    image.jpg

    So it begins

    Edmonton, AB Canada

    Latitude of Edmonton = 53.5444° N

    Latitude of Dublin = 53.3498° N


  • Registered Users Posts: 23,370 ✭✭✭✭Kermit.de.frog


    tenor.gif?itemid=3534162


  • Registered Users Posts: 13,477 ✭✭✭✭sryanbruen


    Interesting thoughts from the Finnish Weather Service for Winter 2018-19. If we could tap into that predicted cold air sometime over Scandinavia here in Ireland and the UK, would be really cold indeed.
    The Finnish weather service has already put its head on the chopping board and announced that this Winter could be one of the coldest Winters since records began. They are predicting a lot of blocking over the mid to northern Atlantic from October onwards. They have linked this to the Atlantic going into its cool phase and have said that by the start of Winter it will be a whole degree below average. The fact that Greenland sea Ice extent has flat lined too in the Summer, has led them to believe that ice gains this Winter could be the most substantial since the 70's.


  • Registered Users Posts: 13,477 ✭✭✭✭sryanbruen


    Time for analogue #3..... and this one is on solar minimum Winters.

    The 500mb height reanalysis of these Winters shows a blocking area of above average heights over Greenland, Iceland and into Scandinavia with a very deep low over Iberia forcing the winds to come in from an easterly direction over the British Isles. Easterlies in Winter can be bone chillingly cold and create very heavy lake effect snow if the sea surface temperature anomalies are well above average. This is a very snowy and cold reanalysis indeed!

    df4d06_9989dba76b57412d92f0e518f6566d15~mv2.png

    The table below shows the CETs for each of the Winters in the analogue. The brighter the red, the warmer the anomaly. The darker the blue, the colder the anomaly. The diff. row is of the anomaly of the mean temperature all of these Winters combined against the 1981-2010 averages. There are a good few cold and snowy Winters in there but of course as always, there are exceptions. The most notable exception is Winter 1922-23 where each of the Winter months were well above average in terms of temperature resulting in up to 2017-18, the 25th warmest Winter on record for the CET. In contrast, Winter 1878-79 was bitterly cold and snowy with it being one of the coldest Winters ever recorded (also one of the snowiest).

    df4d06_94d2b2b392184d08958106f07a95cc1a~mv2.png


  • Registered Users Posts: 1,976 ✭✭✭Artane2002


    I just read that there's a correlation between -NAO Octobers and +NAO winters? Is there any truth in this?


  • Registered Users Posts: 13,477 ✭✭✭✭sryanbruen


    Artane2002 wrote: »
    I just read that there's a correlation between -NAO Octobers and +NAO winters? Is there any truth in this?

    It does somewhat here on my correlation graph but there is still quite a lot of positive NAO Winters that followed positive NAO Octobers.

    dgnqAtn.png

    Top 10 negative NAO Octobers and the Winters that followed:

    osSNkvX.png

    Top 10 positive NAO Octobers and the Winters that followed:

    yi5WBcm.png


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  • Registered Users Posts: 1,976 ✭✭✭Artane2002


    Interesting Sryan, thanks for the prompt reply! Perhaps that may come in handy as an analogue?


  • Closed Accounts Posts: 796 ✭✭✭Sycamore Tree


    2018 has been an amazing for Ireland weatherwise.

    - Great cold spell with superb snow in the Spring.

    - Amazing Summer. So hot and dry.

    - Storm Ali gave us a storm to remember especially in the west.

    However I think this will make our Boardsie Weather folks (have we a nickname?) even more expectant than ever before, and we are an optimistic bunch.

    We are already certainly expecting a serious cold winter with decent snow and we will get very excited about every storm prediction that comes along. And I also think we will want another decent summer next year again!

    How will we cope if these things don't pan out?


  • Registered Users Posts: 13,477 ✭✭✭✭sryanbruen


    Some striking resemblance between September 2018 and September 1946 in terms of SSTs. Very warm anomalies near the eastern US, warm Norwegian Sea, horseshoe shape cold AMO. Although, PDO was much colder then than now.

    gpyDPjy.png

    This reconstructed cross-section of QBO also shows 1946-47 was a westerly QBO Winter. Taken from the paper attached.

    NNouE7j.png


  • Registered Users Posts: 13,477 ✭✭✭✭sryanbruen




  • Closed Accounts Posts: 1,027 ✭✭✭MidMan25


    2018 has been an amazing for Ireland weatherwise.

    - Great cold spell with superb snow in the Spring.

    - Amazing Summer. So hot and dry.

    - Storm Ali gave us a storm to remember especially in the west.

    However I think this will make our Boardsie Weather folks (have we a nickname?) even more expectant than ever before, and we are an optimistic bunch.

    We are already certainly expecting a serious cold winter with decent snow and we will get very excited about every storm prediction that comes along. And I also think we will want another decent summer next year again!

    How will we cope if these things don't pan out?

    I think there's always something interesting happend during a typical winter even if it's not snow / cold. Looking back in recent winters.

    09/10 - Cold + Snow
    10/11 - Cold + Snow
    13/14 - Lots of storms
    15/16 - Exceptionally mild + wet December
    17/18 - No words needed :)

    That's just what I remember off the top of my head!


  • Registered Users Posts: 1,976 ✭✭✭Artane2002


    Sryan, here's another question (sorry if I have been tiring you with all my questions recently, especially the topic I'm about to bring up): I know the Atlantic SSTs aren't great and can result in unsettled weather but does it necessarily mean that the jet stream will be directed towards us and the UK? Or could it maybe take a path towards France instead depending on other factors?


  • Registered Users Posts: 13,477 ✭✭✭✭sryanbruen


    Artane2002 wrote: »
    Sryan, here's another question (sorry if I have been tiring you with all my questions recently, especially the topic I'm about to bring up): I know the Atlantic SSTs aren't great and can result in unsettled weather but does it necessarily mean that the jet stream will be directed towards us and the UK? Or could it maybe take a path towards France instead depending on other factors?

    Don’t be silly Artane2002 :), that’s what I’m here for.

    I will try answer when I can. I have school today as per usual.

    Katla volcano is set to erupt in Iceland and likely to be worse than the 2010 eruption of Eyjafjallajökull. Something is certainly imminent......

    Edit: Thanks Darwin.


  • Registered Users Posts: 2,655 ✭✭✭Darwin


    Sorry for going off-topic, but seems the Katla story has been exaggerated a tad, the study was not making any predictions that Katla is ready to erupt:

    https://www.news.com.au/technology/environment/climate-change/scientific-community-furious-over-claims-volcano-is-ready-to-blow/news-story/0eb97c60009f8d3a7101ebc797444131


  • Registered Users Posts: 6,235 ✭✭✭Oneiric 3


    Currently showing up on my MSN newsfeed:

    iV0xmhy.png

    New Moon



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  • Registered Users Posts: 18,079 ✭✭✭✭JCX BXC


    Oneiric 3 wrote: »
    Currently showing up on my MSN newsfeed:

    iV0xmhy.png

    I assumed they mistook Met Éireann for Met Madden.


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