Winter 2021/2022 - General Discussion

Mild and stormy is my preferred choice. Our winters in recent years have been very benign for Irish winters.

Anything but mild and dry I’m ok with. Mild and dry in winter is so tedious to get through as somebody who loves extremes of all kinds (average blustery conditions or usual rain we get won’t suffice) or just sunny weather as it is usually gloomy, the Christmas holidays of Dec 2018 and Jan 2019 in particular were a chore.

Otherwise, I’m pretty easy to satisfy. Great sunrise and sunset colours like 2019-20 (which made that winter more bearable) I am fine with for example.

Last winter had some great individual days - 6 December ice day with an inversion, 9 January notable severe frost without snow, 24 January localised snow day, 28 February coastal fog which produced a fogbow.

Good analysis @Oneiric 3 I noted similar results in 2018-19; though not as detailed as you've given here, when I last did in-depth winter updates and didn't find the QBO a particularly useful tool to giving an indication towards the future winter but Mets continue to mention it and bring it up.

Sure there'll be another new thing discovered to blame this winter on if it ain't a cold blocked one 😏

I feel we will get a major snowstorm this Winter. Could happen any month and remember if it does it will probably only last a day or two.

Last Winter there was tons of snow in Westport for a day so something more widespread could happen this year.

In general I'd say this Winter will be mild until the new year with the colder weather at the very end.

Usual caveat applies that long range models and teleconnections are notoriously tricky to forecast from this far out.

Everyone has a different variable or element they like to focus on when it comes to long term forecasting guesswork, mine is SSTs. What I'm seeing so far in the long range forecasts for Winter is that the North Atlantic SST profile has a nice warm anomaly, with the large pool of cold which has tended to form between us and Greenland in recent years noticeably absent, and very very constrained once it does appear in the long term forecasts. There is still a small and shallow looking blob of cooler anomalies, but it's far, far more constrained than I've seen it in recent Winters.

Notably, according to Levi Cowan's fantastic analog calculations, the current SST profile globally resembles 2010 most closely. 2017 appears as the fifth closest analog. Both of these Autumns were, as everyone will remember, followed by extreme Winter cold spells in Ireland, characterised by long periods of Northern Blocking over Greenland and the Atlantic, with consequent northerly (Nov-Dec 2010) or easterly (February 2018) spells, respectively.

Here are the anomaly charts for the past month, the same time in 2010 and the same time in 2017:

(Images courtesy of https://www.tropicaltidbits.com/ )

The Atlantic profile is remarkably similar in all three charts, with specific reference to very high SST anomalies surrounding Greenland and Iceland in the far North Atlantic, and warm anomalies directly to our West in both the present and 2010 charts, neutral in 2017. The positive AMO signature is extremely evident in all three charts.

In terms of the Pacific, a moderate to strong La Nina is present across all three charts. The present and 2010 charts feature a negative PDO (that diagonal band of cold anomalies stretching from the US West Coast to Hawaii) while the 2017 chart features a warm (positive) PDO, which had weakened by the time of our Beast in Feb 2018, but not substantially.

The Indian Ocean Dipole is another notable feature - the present day and 2010 featured a negative IOD, while 2017 featured a positive IOD. @sryanbruen pointed out last year that there have been recent tentative suggestions of a correlation between positive IODs and a strong polar vortex, and it's interesting to note that the warm pool in the Eastern Indian Ocean flipped to a cool anomaly in January of 2018, right around the time of the SSW event which ultimately resulted in the gigantic anticyclone that originated over Scandinavia in February of 2018 and drifted Westwards towards Greenland, resulting in our Beasterly. I don't know enough about this correlation to suggest a link between those two events, but it's worth keeping an eye on all the same as our current SST profile would suggest favourability in that area as well.

Obviously the question here is whether these SST patterns will hold over the next few months. I had a look at the CFS and CanSIPS SST forecasts, which are attached below:

CFS:

CanSIPS:

Bit of a mixed bag from these forecasts.

The CanSIPs favours the re-development of the cold pool to the South of Greenland (possibly due to melting ice) while the CFS does not, although it does include a cool blob further south off the coast of Canada. Others who are more knowledgeable than myself can comment on whether the cold anomaly proposed by the CanSIPS to appear off Greenland would be enough to kill the positive potential of these charts, or whether it's too constrained to do so. There are extremely warm anomalies directly below this cool area - I don't personally know how that kind of mixed bag would impact the prospects for blocking, so I'll let others chime in.

As far as ENSO, both charts show a strengthening La Nina, with the CFS switching to a strong event while the CanSIPS doesn't make it as strong, but does extend its reach all the way into and beyond the Nino 4 region in the Western Pacific. La Ninas seem to have a sweet spot with regard to our Winters, wherein a weak to moderate event is ideal while a very strong event leads to storminess - again, others will have to adjudicate on what these forecasts would mean in terms of how strong that La Nina is going to get and what kind of impacts it might have for us.

The Indian Ocean Dipole is difficult to reach from these charts, others can chime in with their thoughts. Looks like an unclear signal in either direction - are Indian Ocean SST forecasts generally this neutral-looking, and does that tend to correlate?

I had a look at the pressure charts (MSLP and 500mb heights) for both November and December in both models, but as each model only shows the anomalies for that period rather than the true values, I'm not sure how to interpret those -  Happy to post them here if anyone else wants to have a go!

From where I'm sitting, this looks like is could be another very interesting Winter of model watching, for those of us who are into our cold hunting!

Pulled from FB.

Yes 😁

It's not ridiculously warm for the time of year. 13 by day, 7 by night would be close to the normal October average.

A long fetch south westerly can give us 15-16C at night as late as December.

We're at the time of year when the seasons are changing rapidly, a few short weeks makes a HUGE difference. By mid-November the ground will be colder, the sun much weaker. Colder nights will happen under any clear calm conditions, even if the temps are still mild aloft.

Watch the temps in the Continent plummet between now and then also.

There's nothing ridiculous about the temperatures. The mean temperature has been about 1 to 2° above average over the past 7 days. That's not unusual when you get a warm source of air for a week or more. To use the term "ridiculously warm" to describe temperatures of only 1° to 2° above average over a 7 day period is what is rather ridiculous and is more akin to the type of language you expect to read in the headlines in The Daily Mail to try make much Ado about something that is not that unusual at all, especially at this time of the year when bigger changes of weather tend to occur.

Had we had northerly winds for the past week and instead of mean temperatures being 1° to 2° above average, they were 1° to 2° BELOW average, would you have described the temperatures as being ridiculously cold?

I spy with my little eye, a CFS run implying higher chances of Atlantic blocking in November and December, and a decidedly easterly looking influence in December :D

One thing that has caught my attention recently is that stubborn warm anomaly over NE Canada/Baffin Bay. It's been there for a while now and seemingly, Incoming Pacific lows aren't strong enough to shift it (yet at least), so... could this lead to a continuation of a relatively stable high pressure zone over that region this winter? If so, then it could help with pushing colder flows further down into our part of the Atlantic.

All just speculation and maybe strong lows will eventually replace that persistent high pressure zone in the nearer future. Who knows.

Is it that time again already :)

Nice bit of navel-gazing from de wannabee national paypurr boy!!!

Snow on Cork rooftops?? Where? All I saw was cigarette ash maybe? :P