The hunt for cold - Model discussion (late November)

[MattStoke]

11 minutes ago, Quicksilver1989 said:

I can think of a few who kept going on about a snowy christmas and severe cold..

Fair enough. Some do get a bit overexcited. The most experienced and knowledgeable posters have always stated late December/early January onwards though. There’s never been much from background signals to support any significant cold from the brief chilly spells we’ve seen so far.

[Derecho]

1 minute ago, MattStoke said:

Fair enough. Some do get a bit overexcited. The most experienced and knowledgeable posters have always stated late December/early January onwards though. There’s never been much from background signals to support any significant cold from the brief chilly spells we’ve seen so far.

If there's one positive to take from the output over the next week its that NE Canada and Greenland are also looking like having temperatures much above average so we may see less of these deep lows passing to the south of Newfoundland. I'd expect the west-east movement of low pressure systems to ease off in the mid to long term as a result.

Problem is we could just get a low pressure system stuck to our west with high pressure to the SE, like in early November. I'd also like to see a drop in SLP over Central Europe. El Nino winters very often tend to be backloaded so I'm looking out for January for pattern changes. They still can't be ruled out for December but the pattern this month is very much what I'd expect for an El Nino year.

Could be worse though, it could be December 2015....

[Mike Poole]

19 minutes ago, bluearmy said:

Can you change the very likely to very possible ??  A split vortex post the displacement remains unclear 

and 80% is way too high for January at this range Mike ...... especially ‘severe cold’. 

Fiona will be even more confused! 

Hi bluearmy. Granted with the first point, but conditional on the split happening in the way that the models are showing, it would bring severe cold in January.  It would be a yes or no question, if it went favourably it would definitely not be a damp squid cold snap, surely.  The uncertainty is all with whether it happens at all, not how severe it would be.

Just to add, I'm not ramping, I genuinely think the chances of a really cold January are now as high as 80%, will apologise on here later if the 20% solution verifies!

Edited December 15, 2018 by Mike Poole

[Frosty.]

6 minutes ago, Mike Poole said:

My 80% figure is from my understanding, such that it is, and what the models are saying, including the long range ones that I have seen.  But you could draw exactly the same conclusion from the Met Office 16-30 day forecast - they would not be so bullish if they weren't pretty damn certain.

Fully agree, feels like it did 8 years ago!..fingers and toes crossed the models start to reflect that wintry extended that mogreps / ec32 / GloSea5 are currently indicating!!!

[snowray]

Well I'm expecting a super dooper 12z, upgrades and more of a block to our north or in the Atlantic by the end of the month.

Something like this.

Edited December 15, 2018 by snowray

[bluearmy]

11 minutes ago, Mike Poole said:

Hi bluearmy. Granted with the first point, but conditional on the split happening in the way that the models are showing, it would bring severe cold in January.  It would be a yes or no question, if it went favourably it would definitely not be a damp squid cold snap, surely.  The uncertainty is all with whether it happens at all, not how severe it would be.

Just to add, I'm not ramping, I genuinely think the chances of a really cold January are now as high as 80%, will apologise on here later if the 20% solution verifies!

I guess it depends if you mean sustained severe cold or a severe cold snap .... sustained is always a tough ask for an island on the western edge of a continent and the eastern edge of a warm ocean .....

[Seasonality]

16 minutes ago, bluearmy said:

I guess it depends if you mean sustained severe cold or a severe cold snap .... sustained is always a tough ask for an island on the western edge of a continent and the eastern edge of a warm ocean .....

Quite, and I like using the example of Sakhalin to contrast. Even narrower than the UK and on more southerly latitudes but with much colder winters due to being on the Eastern edge of the vast Eurasian land mass. 

[East_England_Stormchaser91]

It’s December. Hardly a month renowned for bitterly cold weather, snow and ice. March is by far a better month for getting the goods, despite having more strength from the sun and longer days.

You’ll be hard pushed to find a December with a real vicious dosage of winter. The only ones that come to mind are 2009, 2010 and by the reports and hearings, 1978, that’s about it! 

[Bristawl Si]

7 minutes ago, East_England_Stormchaser91 said:

It’s December. Hardly a month renowned for bitterly cold weather, snow and ice. March is by far a better month for getting the goods, despite having more strength from the sun and longer days.

You’ll be hard pushed to find a December with a real vicious dosage of winter. The only ones that come to mind are 2009, 2010 and by the reports and hearings, 1978, that’s about it! 

For my locality add December 1981.

March? 2018 and......

[Mucka]

1 hour ago, Frosty. said:

Sigh of relief regarding longer term outlook, Exeter shows no downgrade from yesterday..that's a big box ticked!..as I've said earlier, hopefully the operational output improves regarding christmas and longer term..potentially early 2019 could deliver for coldies in the hunt for deep entrenched cold and snow / snaw!

Yes Karl, the only light at the end of the tunnel seems to be MetO and strat forecasts promising better chances of cold in January since GFS has slowly trended to a more zonal outlook over Christmas in line with ECM.

It would take a bit of reversal now to see cold and blocked on Christmas day but just about still a straw to hang on to is the chance of a Atlantic ridge just before the big day.

There have been a few chances of cold in December and some chill in the air with blocking attempting to establish itself but always the Atlantic has overrun it so as usual it is a game of patience waiting for a proper cold spell.

.

Edited December 15, 2018 by Mucka

[East_England_Stormchaser91]

5 minutes ago, Bristle boy said:

For my locality add December 1981.

March? 2018 and......

March 2018 and 2013 left snowdrifts that I’ve never seen before in any other month, not even january 2010 or Feb 2009, which were amazing months for snow by U.K. standards. 

Edited December 15, 2018 by East_England_Stormchaser91

[Bristawl Si]

2 minutes ago, East_England_Stormchaser91 said:

March 2018 and 2013 left snowdrifts that I’ve never seen before in any other month, not even january 2010 or Feb 2009, which were amazing months for snow by U.K. standards. 

2013 was cold but bone dry here.

[Mike Poole]

47 minutes ago, bluearmy said:

I guess it depends if you mean sustained severe cold or a severe cold snap .... sustained is always a tough ask for an island on the western edge of a continent and the eastern edge of a warm ocean .....

Words, huh, they can get you in trouble.  For clarification, my expectation is a more potent version of Jan 2013.

I guess it depends on what I mean by potent? 

Edited December 15, 2018 by Mike Poole

[Mike Poole]

Atlantic ridge evident still on ICON T180, could give that northerly for Christmas day still...

[Bullseye]

Before the 12z run out soon - I have done a brief research of few points that may lead to cold around New Year and Jan. This was on the back of @Steve Murr post in another thread - November AO. Looking at this year we can see the AO for Nov has now come in at -1.116, this adds to following years of sub -1 (per @Summer Sunpost of 2018 value). 

 

When taking this we can compare years which then fall into low solar activity this provides following results - 1952, 1954, 1962, 1965, 1984, 1985, 1995. (I have added in 1984 as this year falls less than 0.5 into -1 for AO in Nov). https://www.spaceweatherlive.com/en/solar-activity/solar-cycle/historical-solar-cycles

Taking these years we can determine which of these years were either decreasing or increasing at stage of low activity per data from above site. We find the following years were still dropping into state of low activity based on monthly sunspots - 1952, 1962, 1984, 1985 & 1995 especially the last 2 years. 

Another one I looked at was the transition of years from easterly to westerly QBO during winter. This was deciding factor as we find that the following years are the closest match - 1954 (although while yr was at low solar activity it was also starting to become more activity solar-wise) and 1984 - this was taken from the Twitter account, credit to gritear. The 3 other years where in a E-QBO phase. 

Both 1984 and 1954 featured warmer than average December against 1981-2010 mean. 2018 also looks to be heading towards much warmer than average month (warmest since the horror of 2015). 

We can also factor in state of play with ENSO region - both years differed to 2018 with both years categorised as weak nina while this year is running at weak nino. https://ggweather.com/enso/oni.htm

Finally, 1984/85 winter also produced a split PV in the first week of Jan 1985 per @feb1991blizzard graph from this week. With continued signs that we may also see split PV happening with continued attacks on PV. Below from Michael.

No doubt I have completely picked this up all wrong and will be corrected! 

 

 

 

 

Edited December 15, 2018 by Bullseye
Correction to years

[johnholmes]

55 minutes ago, East_England_Stormchaser91 said:

It’s December. Hardly a month renowned for bitterly cold weather, snow and ice. March is by far a better month for getting the goods, despite having more strength from the sun and longer days.

You’ll be hard pushed to find a December with a real vicious dosage of winter. The only ones that come to mind are 2009, 2010 and by the reports and hearings, 1978, that’s about it! 

Not totally correct that comment about December

Yes 2010 ranks 2nd since 1659, then 1981 (0.3)ranked 9 th and 1950 ranked 20th (2.0), all in my experience by the way!

To say also that March delivers the goods more then December is probably correct even with the sun higher.

At my low location the 20 years stats show 2 and 3 for days of snow and snow lying in December with March having 3 and 7 respectively. Perhaps a bit of a surprise to some of us?

 

[SMU]

Thanks @Bullseye

Looking at the superensemble mean for the elipses in the stratosphere this morning the score in terms of achieving a split of the vortex ( even when we go negative on the zonal wind & we have a technical SSW ) it was 0 out of 64 runs.

So a displacement is near 100% at the first time of asking...

[Mr Brown]

2 hours ago, Mike Poole said:

My 80% figure is from my understanding, such that it is, and what the models are saying, including the long range ones that I have seen.  But you could draw exactly the same conclusion from the Met Office 16-30 day forecast - they would not be so bullish if they weren't pretty damn certain.

Good point. 

[Weather-history]

18 minutes ago, Bullseye said:

B

 

 

 

 

I don't think winter weather lovers will complain of a repeat of 1954-55, January to March had cold snowy spells of varying lengths and severity, there was even snow the following May but a superb summer was to follow.

December 1954 was very mild. 

Edited December 15, 2018 by Weather-history

[feb1991blizzard]

4 minutes ago, johnholmes said:

Not totally correct that comment about December

Yes 2010 ranks 2nd since 1659, then 1981 (0.3)ranked 9 th and 1950 ranked 20th (2.0), all in my experience by the way!

To say also that March delivers the goods more then December is probably correct even with the sun higher.

At my low location the 20 years stats show 2 and 3 for days of snow and snow lying in December with March having 3 and 7 respectively. Perhaps a bit of a surprise to some of us?

 

You could actually also make a case for January (sounds absurd) not really ever consistently delivering throughout a whole month very often at all during my lifetime, yes i have experienced my biggest dumpings and a lot of my potent cold spells in Jan but a lot of the very best cold spells in Jan did not last very long and i have had an awful lot of zonal Januaries, i think there was even a summary from a respected meteorological organisation once on each month of the year and the average UK conditions and they described Jan as one of the most Atlantic driven months of the year, Feb really is the month of blocking but that seems to have changed the last few decades.

[Mike Poole]

5 minutes ago, Steve Murr said:

Thanks @Bullseye

Looking at the superensemble mean for the elipses in the stratosphere this morning the score in terms of achieving a split of the vortex ( even when we go negative on the zonal wind & we have a technical SSW ) it was 0 out of 64 runs.

So a displacement is near 100% at the first time of asking...

I don't think anyone thinks there will be a split at the point of the technical SSW, Steve?  At least I haven't heard anyone say so.  It is the second time of asking that is of interest...big interest.

[snowray]

UKMO at T144, signs of HP building towards Greenland there. Not too sad.

[Ice Day]

5 hours ago, weathergeek said:

I have to say, I've been an avid reader on here since 2011 and despite having learnt a lot, I still class myself as a novice too. I still may not be an expert chart de-coder BUT I have been through enough cold spells/beasts/potential beasts/fails etc and have read enough of the corresponding posts to understand how these things work and play out..... it shocks me that although I class most members in here more knowledgeable than me, I see the same comments rolled out time after time. We are undoubtedly in a very obvious "flip flop" situation at the moment due to the models not being able to grasp the unique situation we're in. Although I can't guarantee they will all end up showing a Snoasis, we just need to keep looking at the broader theme and watching all the other indicators and not just the run from run ☺

Just catching up today and I loved this post from weathergeek, it's absolutely spot on. We know there's an SSW coming, maybe two, we also know from experience that ALL the models will struggle to get a handle on how these massive stratospheric changes will manifest themselves in the medium term.  Last year there were complaints that the SSW came too late in the season, however this year it's very different, we could be getting two before December's out.  How this pans out for our small corner of the planet remains to be seen, but in my opinion we could not be in a better position for an early 2019 cold spell

[WINTRY WALES]

16 minutes ago, Mike Poole said:

I don't think anyone thinks there will be a split at the point of the technical SSW, Steve?  At least I haven't heard anyone say so.  It is the second time of asking that is of interest...big interest.

When is the second warming scheduled....which hopefully leads to a split?

[snowray]

42 minutes ago, Mike Poole said:

Atlantic ridge evident still on ICON T180, could give that northerly for Christmas day still...

Yup, looks like our best chance for something white over Christmas and wouldn't it be nice if it extended into Greenland as we go into the new year.