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Long-range forecasts for winter 2021-2022

  • 09-10-2021 8:55pm
    #1
    Registered Users Posts: 13,204 ✭✭✭✭ M.T. Cranium


    I thought it might be interesting to gather any and all long-range forecasts (for Ireland) covering the winter of 2021-2022. That would be the period from 1 Dec 2021 to 28 Feb 2022, but November and March outlooks can be included.

    In my own case, still working on an outlook, should have one ready to post within a week or so.

    If you do post a forecast, let us know anything you can about the reasoning or methodology. You may be just reporting a long-range forecast from another source, if so, mention where you came across the forecast. Any forecast meant to apply to Britain can probably be included but see if there is any obvious modification that might apply to Ireland.

    The three main LRF techniques that seem to be commonly in use are these:

    -- teleconnections, a study of certain global or regional parameters, and how those have correlated with Irish weather in the past;

    -- analogue techniques, which broadly speaking include the above, but can be more limited to data analysis for just the local or regional data;

    -- model extensions, based on experimental monthly- or seasonal- scale output of global models.

    In my own case, I attempt to keep files on index values of numerous parameters that I believe may be part of the natural variability of the atmosphere, and update these as the research (sometimes) uncovers new categories. This has provided somewhat of an improvement over random forecast output although some seasonal forecasts have performed better than others. It remains a work in progress and it remains elusive to prove that these index values are the main component of the variability, or just a portion.

    There is also the ongoing trend of milder winters but in statistical terms the increase is only about 10% of the standard deviation so it is hardly overwhelming variability to the extent that we might as well just say "milder than last winter" each winter.



Comments

  • Registered Users Posts: 8,409 ✭✭✭ Danno


    I think with the meandering jet stream that a cold-mild-cold rollercoaster is on the cards, but rather than a zonal flow, we'll see more blocking with occasional topplers coming through.

    Rainfall below average

    Temperatures below average with a few notable mild spells

    Wind slightly below average

    Snow slightly above average (frequency rather than amounts)

    Frost well above average

    Sunshine well above average - possibly record breaking levels.



  • Registered Users Posts: 2,728 ✭✭✭ Rebelbrowser


    Just out of curiosity, I went through the CFS just now out to mid March. No real notable cold but not a particularly mild winter either. The coldest spells (all unexciting) were around 14 Jan, 26 Jan and mid/late Feb. Mid Jan the best with a toppler turning into a little bit of an easterly but temps barely getting to -6/-8s......



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  • Registered Users Posts: 1,860 ✭✭✭ Cork2021


    So from what I’m seeing here is we’ll definitely end up with a storm Emma situation this winter! 😂😂😂



  • Registered Users Posts: 13,204 ✭✭✭✭ M.T. Cranium


    Well that did come at the end of a rather bland winter with a steady downturn in temperatures in late February, a three-day cold spell with lots of snow, and another brief cold spell about two weeks later with limited snow. Long-range forecasting is at a rather early stage of development and is more likely to catch overall trends than very specific events that may not have much persistence. A more spectacular change in the circulation that lasts for weeks, as in late 2010, might be somewhat easier to detect.

    About that warm pool in the north Pacific, its influence is going to depend on the wave shaping -- if we get a shallow trough east of the Rockies and a lot of Pacific air flowing in, then cold shots will be very brief in the east, but it there's a larger amplitude wave pattern with the trough a bit further east than that, a lot of cold air can escape the arctic while milder Pacific air gets directed further north so that places like the Yukon and Northwest Territories get anomalous warmth. That's a fairly frequent La Nina outcome. The correlation with downstream weather for Europe is very weak as Oneiric3 noted.



  • Registered Users Posts: 5,852 ✭✭✭ pauldry


    Ya I'd say until 2022 we won't see cold shots too much here until its supposed to be Spring it will probably be Winter then and be 15c in December



  • Moderators, Science, Health & Environment Moderators Posts: 15,179 Mod ✭✭✭✭ Gonzo


    I'm not expecting this winter to be any different than most winters. Mostly mild or very mild particularly around Christmas and during February. We have generally been on a significantly warmer than average cycle since February 2021 with the exception of April and May. This is turning into a warmer than average Autumn and I expect this to continue into the winter, just more unsettled with plenty of south-westerlies along with some cooler north-westerlies. Best chance of cold probably in January and again in March when winter is over.



  • Registered Users Posts: 958 ✭✭✭ esposito


    Ya Christmas will be mild. It’s a rule at this stage! Wouldn’t be so sure about February though.

    Anyway, what will be will be.



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  • Registered Users Posts: 5,852 ✭✭✭ pauldry


    Ya can't say what will be will be in a weather forecasting forum you've got to speculate!!



  • Registered Users Posts: 981 ✭✭✭ Lucreto


    I am slightly more optimistic of a colder winter. After 2018 snow we had mild Winters but last winter was slightly cooler with more frosts.

    Also a decent cold snap happened either the winter before or after a heat wave. We had one of these this year. I also see the effects of the solar minimum this year.



  • Registered Users Posts: 13,204 ✭✭✭✭ M.T. Cranium


    Bumping this thread as there was a question relating to long-range forecasts in the main winter discussion thread. My own outlook has not changed much and I continue to be somewhat optimistic that we will see one decent wintry episode from blocking high pressure over central Europe or southern Scandinavia but question remains how strong the impact will be this far west. The dry November is overall a positive sign too. But there will probably be some mild or even very mild spells in the winter too, so it may be the case that one decent wintry spell and a few minor cold spells will be about the best we can get.

    As we are getting closer to the actual winter season now, I hope to see a few other forecasts added to those already posted.



  • Registered Users Posts: 812 ✭✭✭ lapua20grain


    Have you already done your winter outlook? I haven't seen it if you have



  • Registered Users Posts: 812 ✭✭✭ lapua20grain


    Never mind I've just seen it in the winter thread



  • Registered Users Posts: 6,122 ✭✭✭ squonk


    Would you mind putting your winter forecast in its own separate thread please MT? I believe you’ve published it somewhere here but I’m damned if I can find it. It would be nice to have a dedicated thread for these long term forecasts from MT please Mods.



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