Phil

Uh, no..

Based on the observed, ongoing, and climatologically favored progressions of the tropical forcings, stratosphere, and interactive waveguides, I think the first window (for the western states) is from mid/late December to early January, followed by another window in February.

Haha, it looks quite cold to me, just not historically noteworthy. By historically noteworthy, I mean something like a western version of February 2015. Could be a dry blast if that's significant, I really don't know. Just pointing out the potential.

FWIW, I feel very strongly that as long as February doesn't flip into a +AO/+EPO, there will be a very significant Arctic event that month sometime. Don't want to get too far ahead of myself here, but I think there are a number of indicators that favor such a progression.

Modeling aside, I'm confident in a cooler than average December across the PNW, with an opportunity for a significant lowland snowstorm between December 20th and January 5th, followed by a period of ridging thereafter. I don't see a significant Arctic blast until at least late January, as far as widespread cold is concerned, with February offering the best opportunity for some very cold air.

I've always had hope. I'm just leaning towards something more backloaded overall, given the poor equator/pole synchronization that's manifested over the last 8+ weeks. I do expect a mammoth EPO/AO plunge around the holidays and/or just afterward, with a corresponding Arctic shot over the nation. How that unfolds is still in question.

Energy spills too far offshore.

That's some purrrrrty blocking on the clown range GFS. La la lock it up.

I think the cause/effect jury is still out. There seems to be plenty of literature on both sides of the isle regarding the nature/reason(s) of/for Arctic amplification, and if/how it may either impact and/or arise from changes in circulation. http://www.tellusa.net/index.php/tellusa/article/view/25482 http://onlinelibrary.wiley.com/doi/10.1002/wcc.337/full http://onlinelibrary.wiley.com/doi/10.1029/2010GL044136/full https://www.atm.helsinki.fi/peex/images/Workshop_proceedings_NERSC-Tech-report_290216-MASTER_ESAU.pdf#page=16 http://onlinelibrary.wiley.com/doi/10.1002/2015GL065923/full http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-16-0320.1

Haha, sorry man. Can't seem to get facebook notifications to show up on my new phone.

Thank you. FWIW, my concerns were/are confined to November and early December. I never was nervous about the winter failing.

Minor timing issues aside, I like my winter idea, at least for the time being.

The 00z looks very 1983/84 esque. Under the modeled global progression, most of the country would plunge into the freezer from mid-December right through New Years. Regardless of the current modeling, I think a significant and widespread Arctic blast is likely in late December and/or early January over much of the nation. Exactly where remains to be seen, however.

Anticyclonic breaking does occur in the GOA, however I don't see anything supplementary wavebreaking downstream or poleward of the ongoing break. So, will be tough. Still a better look than anything we've seen since..August?

Yikes..only 96hrs in but can already tell the precursorsory anticyclonic wavebreaking in the NWPAC is much weaker on the 00z GFS. Could be a +EPO or poorly placed ridge scenario if the misalignment continues.

Lol, dude you're the best.

That's a classic -NAMT look. Retrogression would occur within approximately 3-4 days thereafter. I also think that strong Hudson Bay ridge is crucial to obtaining most effective -NAMT assisted retrogression.

Funny how after all the hand-wringing, the modeling is trending right into your typical -ENSO/+QBO climatological progression. Of course, that's party/mostly because the intraseasonal forcing is constructively interfering with/mirroring a Niña Cell..that will change in mid-December, where an EPO spike may be favored before forcing reaches 150E and beyond in late December, which should force another round of NPAC wave breaking.

Or, maybe the warm Arctic was/is a result of the unprecedentedly strong -NAM and weak stratospheric PV regime that's been ongoing since September? A weak equator/pole thermal gradient is something you'd generally expect from a -NAM/weak PV regime, not necessarily a cause. Where the PV has been located (Eurasia), record breaking cold has been observed. Back in early September, the polar stratosphere became heavily perturbed/warm relative to average, and the troposphere followed a few weeks thereafter. No?

The best models runs always roll out when I'm napping. Lol.

The winter weather you experience in Chicago will probably blow away anything you'd experience in the PNW. So, at least there's that.

I'm with you, perfect job for a weather freak. I'm honestly considering staying in the landscaping and tree care business even after I complete my degree. I enjoy it too much, and if/when my body gives out, I won't be able to go back. Also, being way up in trees cured my fear of heights. Therapy by exposure, I guess.

Funny, I currently work for a landscaping/tree care company, and I also love it. Pays my tuition and keeps me in shape.

End of this run shows how a broad/flat NPAC anticyclone is the ideal conduit to an Alaskan vortex/+EPO. Any "Pacific shutdown" is a pipe dream under such a scenario. Need to maintain a poleward displacement of mass to shut down the jet/manage a proper -U wind anomaly.

Doesn't quite get there..Alaskan vorticity about to return as a big anticyclone sets up in the NWPAC. #flatridging