oasis

Someone on TWO mentioning that active hurricane season years are more likely to see significantly colder Decembers. Interesting. Here's hoping.

Also what I thought - 1 degree or so ain't gonna do much to an ice day. Unless he's more refering to the Arctic being warmer the last few years, and even then, as you say continental shouldn't be affected.

A true greenland block that we haven't seen for a while, I was wondering what are the rough maximum temperatures (with Arctic temperatures at normal) you'd expect in each month of the year they happen? In, say, Manchester, roughly middle of country. To start, I'd guess 8-9 degrees in late October, 6 degrees in early-mid November, 2 degrees in Early December (was that the rough maxima in December 2010? And mainly ice days from mid December to Mid February? I guess, the main point, I'm making through this, is at what point does extensive northern blocking become "useful". No longer what some would call a waste. That which will give a decent week long snow event, not a morning of wet snow like in late October 2008 (I think it was 08). Can anyone remember a week long snow event in Mid November from extensive northern blocking centred on Greenland?

4-6 degrees projected in this far out scenario. What would such a block give a month later, ice days?

I was struggling to find stratospheric archives, but from what I could see the only really good match on the other conditions is 1996-1997. A winter with a cold December (2.9), and a cold January (2.5). 1956-1957 seems to have been after the solar minimum, not before. For what it's worth, that winter was mild. Though there was a white christmas in places.

The state of the Arctic accepted, there are some potentially interesting parallels to 1962-1963.Adding to what has already been written. ENSO 1963: ENSO neutral in 1963 verging on weak La Nina. http://ggweather.com/enso/oni.htm ENSO 2017: Uncertain. Forecasts range from ENSO neutral verging on weak La Nina, to Moderate La Nina QBO 1963/2017: Both easterly QBO. Solar activity 1963/2017: Both winters taking place in the low part of the solar cycle Stratosphere 1963: From my understanding Canadian warming and subsequent weakening of vortex in early winter 1962. Stratosphere 2017: Zonal wind plot forecasts suggesting polar vortex may start the season weaker than average. http://www.atmos.albany.edu/student/hattard/realtime.php So, there you have it, La Nina could go moderate and render the parallels to 1963 obsolete, the polar vortex could suddenly ramp up strength after a promising start like last year, but interesting nevertheless. How many winters in the last 100 years have met 1963 on all the above conditions? I am a believer in nature "balancing itself out", as it were, and with our recent mild winters streak, and drought in Spain, feel perhaps a winter with lower pressure over Europe is due. I think 1962/1963 gave something like 300% of usual rainfall to parts of the Iberian Peninsula (as did 2009/2010)

so if causes are like soot are a big contributor, would the amount of soot eventually hit a ceiling, and the rate of arctic ice decrease start to slow down, as "just AGW" becomes the main forcing contributing to further ice loss? Assuming industrialisation, coal etc, in Asia has hit a plateau, and feedbacks don't cause runaway melting.

Very interesting. Thanks for that. So if the scandi heights can hold on... Plus what has been mentioned about possible MJO activity, and angular momentum, then I guess potentially interesting times. I recall someone with a lot more knowledge than me - I think Tamara? - saying as well what happens if a spike is put into a vortex which has rapidly intensified in a short period of time. Something about the higher they go, the higher they fall perhaps. Here's hoping - from a cold perspective. Also those composites from Gp earlier. hmmm... Edit: If angular momentum can just stay around neutral, that could help make things more interesting. As Singualrity has pointed out its not falling as quickly as predicted. I suppose the current models are conditioned on the fall in angualr momentum occuring as predicted.

Though some may disagree, if the russian high can cling on a little bit, warm 850s can get pushed into the arctic, then that can be a trigger for the wave 2 action, as mentioned by GP in strat thread. Hopefully such wave 2 action could push back against the downward propagation of insanely high zonal winds. Also of note Anthony Masiello on twitter mentioned that we're in a - EPO state? Which apparently couples well with wave 2 action when it comes to impacts. Seeing the insane push of "green" 850s into the arctic could lead to colder impacts down the line. Edit: The more directly that warm air can go into the arctic, the less the siberian cold pool will be pushed back - I think.

I think Roger Smith deserves a few kudos for his winter forecast. Not entirely accurate, but certainly predicted after new year storminess, along with mid January cold spell. Will the super cold February materialize?