If I had to pick a week for the only winter cold spell it would be the week leading up to Xmas. 2010 was pretty good in that regard.

A short update on latest indices.Note that METO in their 3 month outlook for NDF conclude that lower than average temps are more probable than higher than average  values

1ENSO.

Latest NOAA diagnostic discussion goes for  a weak La  Nina for DJF (as dose METO).In METO's words "A La Nina-type state is expected to diminish the strength of the normal westerly flow across the UK inearly winter.

Weak La Nina winters were 1957,60,62,63(No ramping!)67,81,84,8697,02,13,14.

2 QBO

October had 12.83 v 10.48 in September.Now 17 consecutive QBO+ months a new record.However no correlation between QBO and winter NAO.

3.SST's

Meto concludes that SST patterns do not have an important influence on this winter

4.Sunspots

Dropping from 44.7 in September to 333.6 -a slow descent to the solar minima in 2020.

5. Probability Maps.

METO November update not yet available- this update will be of particular interest For what they are worth CFS maps show near average temps for November and mild for DJF.

What happened to the season of 'goodwill to all men'?

But yes, given the choice between MBY or anyone else's I'd choose mine every time. Although, saying that, I genuinely would like the entire UK to be covered in snow.

I have had a look at what the QBO was doing in each of the months from December to March since 1987 which have been significantly below average. Here is what the numbers look like.

The standard measure of the QBO which is quoted is the figure at the 30hPa level. However, data is available for points from 10hPa down to 100hPa as above.

If we look at months where the QBO was heavily negative (easterly) at the 30hPa level we find this was the position in only 12 months out of the 26 cold months highlighted above. In the other 14 cases the QBO was either positive or fairly neutral at 30hPa.

For those 14 months I then looked for other patterns in the QBO data. In four months we find that there very negative readings between 10 and 15hPa. In another 7 months we had very negative data just below the 30hPa level between 35 and 50hPa.

There is one month, March 2016, which does not really show any pattern at all - the numbers are all over the place. This is perhaps not surprising given the QBO this year has done something not seen since 1950 - the easterly QBO tried to develop early this year and then failed to fully propagate down through the atmosphere.

The closest matches in the table to the current QBO phase we are in are December 1992 and December 2010. These show generally positive figures throughout except close to the 100hPa level where they are negative.

In order to get a true reflection of whether the 2016 position is similar to those years I then picked out the October QBO data for 1992 and 2010 and compared it to 2016. What we see is that the 1992 data is not that similar to 2016 but the 2010 data shows a very close match apart from at the extremes at 10hPa and 100hPa. But the signage is at least the same even at these levels.

Now I am not suggesting for a moment that we are going to see a repeat of December 2010. I am just noting that the only time since 1987 we have had a cold month in the winter when the QBO was in a similar state to what it is now was in December 2010 / January 2011. There are of course many other factors that impact whether we see a cold winter.

The 2010/2011 general pattern would certainly fit with what many are saying about what this winter might bring which is that we are more likely to see colder weather in the first half of the winter and perhaps warmer weather later in the winter. The latest EC seasonal model that Gavin P has discussed on his website today supports this general theme.

December 2010 was of course very cold. January 2011 was also a cold month. Overall it was not that cold in January but the first 10 days saw a CET of 3.0C and the period from 18th to 31st saw a CET of just 2.0C. This was offset by one very mild week from the 11th to 17th with a CET of 8.1C.

But overall most of December 2010 and January 2011 was cold or very cold. Could we see something similar this year (albeit probably not as extreme)? We will have to wait and see. There are some other factors that are potentially helpful for this winter including:

• very high snow cover across Scandinavia by the end of October,
• declining solar activity which is continuing to reduce to relatively low levels at the moment,
• strong hurricane season
• potentially weak La Nina conditions (we have had two rolling 3 month periods with ENSO <-0.5 so far)
• sea temperatures rapidly cooling in the NW Pacific (warm waters here in the past 2-3 years may have helped give us particularly warm winters)
• very warm temperatures in the Arctic at present helping to boost the blocking to the East of us and generating a very deep cold pool over Siberia

So plenty of positive indicators and the fact that the QBO at 30hPa is in a positive phase does not in itself preclude some cold weather this winter. Indeed about one-third of the cold winter months since 1987 have been during a strong westerly phase of the QBO.

At the very least it looks like this winter we may see very different conditions to what we experienced over the past 3 years. Impossible to predict whether there will be significant / prolonged cold spells but the chances of that happening look better than average this year.

You'll have to explain that one

That's one of the most insightful and downright useful posts in TWO history there GW, you are truly a legend of our time 

In Dec 2010 we had some brilliant troposphere-stratosphere interaction but with a strong La Nina and not very prominent snow albedo feedbacks, we were always up against it when it came to sustaining the blocked regime with reverse zonality through the rest of the winter. That we fared as well as we did in Jan 2011 was an achievement in itself.

This year we don't have that troublesome tropical forcing and the snow albedo feedback is looking mighty. We also have an exceptionally weak vortex state. So it becomes more a question as to whether we can see such effective stratosphere-troposphere interaction to see some crazy weather in late Nov and Dec to kick things off.

I do have that feeling of impending excitement now, which makes for a nice change 

Just looking at met office CFS updated .

Shows above average temperature s for the UK and most of central Europe around average or below when last month it was the other way around.
Also the northern Atlantic and pacific cools and equatorial pacific warms.
Is this their mild bias? But is this game over for the UK ? Ita showing all the UK? Or is it uncertainty and as alluded to - their mild bias.?

http://www.metoffice.gov.uk/research/climate/seasonal-to-decadal/gpc-outlooks/glob-seas-prob

Well for starters that's not the CFS...That's the Metoffice GLOSEA5 long range model.

Secondly I'd advise not to take much notice of the 2m temperature anomalies on any long ranger as they always seem to be very sketchy. The MSLP anomalies are the most important to me. 

I'd say that (especially in the Jan-Mar period) we see a battleground Britain scenario on the GLOSEA model with the jet diving down through the UK from the N&NW and LP meeting colder continental air to the E.

I find it helps to look at the two category charts.Looking at this;

Pressure shows little variation from the norm except for small areas of  slightly higher than  average HP to the N and NE of the UK

SST's  a large area of lower than average SST's in Mid Atlantic south of Iceland,and broken patches of colder SST' s to north sand NE of Scotland

Precipitation Most of the map covered with normal precipitation.Exception is Northern/Russian  Arctic where large areas strongly above normal precipitation.

Temperature.Resoundingly above average temperatures.

The problem is that the METO had hinted of a winter of two different halves colder first half,warmer second ,so the average could be misleading.

However when you look at CFS charts which have monthly splits mild dominates in every winter month!

The latest Met Office probability maps don't seem to suggest a colder than average winter. I agree that 2m temps can be misleading but 500s suggest a slim chance of lower heights over southern Europe. How would I marry this to the media statements? The only thing I can think of is the probability of a cold December followed by mild January and February. 

That doesn't fit with the 700 hPa anomaly charts, well at least not for Dec... I think that Jan-Feb is a classic case of the model overdoing the low pressure systems in the Atlantic even as and when they undercut the blocking highs. I've seen that many, many times with the model in the past, and the GFS used to be guilty of it at times - less so these days but with the GEFS still susceptible on occasion.

I'd not be surprised if the trough disruption mechanisms typically involved when blocking highs are at large are not able to be adequately resolved by any of the longer-range models, including GloSea5. So with a block to the NW and low pressure undercutting, mild southwesterly winds keep making inroads when in reality the low would be less organised, tending to elongate with a secondary feature splitting off and heading into Europe, so allowing the cold air to remain entrenched.

Now, I'm loathe to post CFS charts given it's dodgy track record, but they're worth a gander for entertainment value:

Blocking, blocking and more blocking. 

Let's just hope we don't end up with a high-latitude b0ll0cking instead 

Following on from my earlier post - I looked at some data going further back, and 1977 turned out to be another strong match for 2016, in fact the 70 hPa level is within 5 m/s of 2016 for the entire period Jan-Oct. Who fancies another blizzard of '78?! 

Hi Brian,

The Metoffice charts that you posted suggest to me that average sea level 500 hpa heights will be higher than normal through the main winter period to our north and over Scandinavia. And these charts tie in quite nicely with the ECMWF seasonal updates which also point to higher than average heights to our north during the winter period. 

My hunch based on the seasonal model outputs that I have seen this far and various winter updates is that December to mid january will see the coldest winter weather this season with the cold moderating after mid January some what.

Whilst I very much doubt we will see a December 2010 scenario this year, I think that we could see a potentially cold December akin to December 2009 and a cold start to January with a moderation of the cold as we head into mid and late January.

I do feel that this winter has a lot of wintery potential especially when you compare it to the last 2 or 3 winters.

Grant

I have to agree. What particularly worries me is that orange shade between the Azores and the Canaries in the topmost chart. A 60-80% chance of higher-than-average heights in that region would scupper any chance of wintry weather for the British Isles. How many times during winter do we comment plaintively that nothing cold is coming our way until that Azores high disappears?

On the plus-side, I don't give these ensemble outputs much credibility at all, whether they're from CFS, MetO or ECM. You only have to look at the gigantic range of solutions in the model output ensembles for Sunday night onwards right now to start feeling dubious about the same spread of results being extended for another 3 months.

Can't argue with that. But still a lot simpler for the British Isles to access cold when there's no ridging in the Azores at all. Rather than hoping the Azores High is tilted NW to SE, I'd prefer some areas of even the weakest low pressure down there, so there's nothing to prevent the jet stream diving south and bringing southerly tracking lows with it.

But I take your point. It doesn't rule out cold, even though it makes it a little more difficult to justify a cold forecast.

Spot on IMO

http://www.cpc.ncep.noaa.gov/products/CFSv2/htmls/euT2me3Mon.html

Just looked at latest CFS monthly forecast maps for temerature As I understand it E1 is the earliest run (which shows mild) whilst E3 is the most up to date which shows a much colder scenario for much of Europe in December in particular.

Is my interpretation correct?

Even managed about 20cm here in the suburbs of London from that event which was better than anything here since and before that had to go back to the "wrong kind of snow" back in 1991 to better it

Long since deleted from TWO but the "Wayback Machine" has a cache of the TWO page from that time showing page after page of snow pictures (where the photo has not been moved).

https://web.archive.org/web/20090204144013/http://theweatheroutlook.com/twocommunity/forums/t/24338.aspx

(slow to load)