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Something to keep an eye on during the next few weeks, as it appears to be an interesting set-up .

I know you touched on this already, to a degree, but do you have specific research that shows in this semi-new climate era from say 2010, that when November is winter-like then the winter attempts to mirror that outcome in the following March as well ? If anything, it seems winter starts later, taken into account the November head fake and then lingers longer. The linger longer part I imagine has to do with delayed seasonal blocking and any related lag effects from possible PV weakening. Last March many thought it was going to deliver, but it really didn't to the full potential some said it would, but oh boy April was cold. The year before was an epic March I even think the maturing of the event was responsible for the less hot June and July, relatively speaking. Thanks

For someone with Weather Bell access I am not privy to what the Euro ensemble shows for the AO, but the lastest CPC AO forecast shows more spread today. Can't post the 11/7 update here is the link https://origin.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao.shtml

I don't have an answer for this. I know last year Isotherm had mentioned he thought we might be nearing a period of more frequent - NAO cycles. Some research points to the sun effecting the ocean currents in the NAO domain, which can lead to a seasonal - NAO, but in this area I think the lag might be as long as 2 to 3 years. I know HM wrote something a few weeks ago about the NAO , and I personally thought it implied he did not seeing long periods of NAO . Whether he meant that for this month or this coming winter, I am not sure. I would have to search for the post. Here is what Isotherm wrote " There are other factors forcing the mode as well. Furthermore, as a general and practical matter, the descent of the solar cycle tends to force a greater frequency of positive NAO periods. My NAO formula suggests that the mean will be positive for DJF. This is not a deviation from most winters of the past decade. "

Very true. He also highlights on AAM, atmospheric angular momentum and the momentum budget and stuff like that. Hard to say if we go towards his solution. Last year Tom thought we did not need a SWWE , and I believe he might have hedged against a wind reversal and a true SSWE. In the end that did happen. Did it take full responsibility last year for the poor performance of many humans and machines, not sure. Some mets commented last winter the models saw the warming at HL and went with the idea that blocking would indeed develop over the AO and the NAO regions due to the Dec SSWE. It never happened and hence the awesome look by the weeklies and other models never occurred. We have mentioned many reasons why , the pure lack of tropical forcing, the ocean and atmosphere not coupling, the December SOI which was positive not negative. Not what you would expect. The MJO being effected in the warm cycles by the SSWE. The basin wide Nino and the very fast Pac jet, and High pressure in the Central Pac that enhanced a SE ridge. ( Nina like ) Everything went haywire and there was no cooperation and sync if you may. You would have thought the blocking should have descended to effect our sensible weather but many blame the QBO as a road block to that not happening. last Jan. This year we have a more favorable QBO. I also think I read in Tom's winter outlook where he stated in low solar min the NAO is more so positive, not sure but I think I read that, if so, I wonder what makes some solar min winters so freaking cold when I looked at previous solar min winter since 1950.

I liked your post but then I got it ....... so here you go

Looking like maybe we do not lose the trough in the East later in the month. I like the signal for the Kara Sea ridge Also, the consider the MJO as well for later in the month and then continuation of the progression would lead to a warm up in early December.

I don't follow Larry, but I can tell you Isotherm does have a good record at predicting the seasonal trends. His forecast for the next winter is anticipated by many every late Fall.

I post the positives and negatives - for those that wonder why - simply to make sure I am not biased cold and snowy. I love snow, but I attempt to be more realistic as I age. Chatting with bluewave about this November, just like last November we are doing great in terms of almost record high NH snow cover. I use to think that was awesome. What was viewed before as a great signal to a colder winter ( Judah SAI) has waned. We lost the snow last December and might lose the snow again this December if the warm December forecasts are correct. The changing Pac along with lower sea ice and other features are acting to put down rapid snow cover in October leading into November only to fall back versus above normal values in December. Damn I hate looking at those maps. from bluewave: <<< The cold November followed by a mild December has been a very persistent pattern this decade. So the snow extent charts are just reflecting this new regime. >>>

Well you decide. Personally I can see a shot gun of outcomes. What do you think? As HM states, a shoe-in for a warm December , right ? Only a couple mets I follow are going for a normal or colder December.

Pretty impressive SST anomaly and the waters North of Alaska are still ice free. I am beginning to appreciate more and more how climate change is changing the drivers of weather. Not only with recent Novembers but even with how storms are tracking in the lower latitudes. In part from the HC and height field compression .

This is an interesting precip signal from the seasonal . Wonder how active the Northern Jet will be ? Progressive disturbances, versus, do we ever get upstream blocking to develop. Everything last winter either flew by or lacked proper phasing.

Is the EPO loading pattern / low sea ice, other N Pac features forcing these colder Novembers since 2012?

Eh, that stinks and icing on the cake was reading Isotherm's winter forecast. If I didn't value his insights as much as I do I would throw his forecast aside. But, I can't.

Well......... deja vu anyone Just like last year to the date per Bluewave , ( record high NA/NH snow cover ) wonder if we face the same scenario as Dec 2018 come this mid December, when the NH snow cover dropped rapidly. What looked so promising changed so quickly as warmth over spread the land. https://www.star.nesdis.noaa.gov/smcd/emb/snow/HTML/snow_extent_plots.html

I am sure you recall last year, looked great and was great but we hit the middle of December and poof, we lost a lot of the snow cover in the States and in Canada. Notice that dramatic decline in the graph around the second part of December. We would recover eventually, but not till mid Feb. ironic. Wonder if we are destined to the same outcome this year? You would have thought the snow cover might have aided in the delivery of cold air masses into the states, but alas it seems the ones who did benefit the most were the Northern Plains and Northern Maine.

Wow, this is a huge surprise, and then again not so surprised. I value your research and insights, thanks for the time in putting this together @Isotherm Personally I feel we do a generally normal winter but we can revisit this in later March. Isotherm's Winter Forecast http://www.lightinthestorm.com/

Hmm. interesting just apply some pressure and keep it weak. Remember there is talk that the seasonal models may be getting the idea of a + NAO and a + AO from the forecast of a very strong winter PV this coming winter. If that is true, and the PV is weaker instead, we might be a different outcome. Read from BAMMWX that SST models and the data from them that goes into the seasonal models ( and also SST ocean modeling in general ) is prone to significant fluctuations regarding accuracy. Many times the forecast for a certain SST -state months out in the future never really verifies well. BAMMWX stated they studied this and found only about 19 % of the time was the forecast accurate. I am not sure the details and the specifics, but I found that an eye opener. Wonder how much that data effects the seasonal models? Personally, I am sure it does, as the oceans are a huge weather driver.

Glad to hear you think this winter has potential coming up Bob. The eventual moderation and warm up will make many feel bummed, but it is a natural process. Difficult at this time to pin point when we moderate. Rolling forward the phases and the retrogression hopefully not more than a couple weeks warm up. Where last December we broke records for the MJO being in the wrong phases/very high amplitude this December maybe we continue spending the most time in the colder phases. Certainly it has been going that way to a degree. When the pattern reverts back to more winter-like you have to think we might be in prime time. I also read something recently that stated the progression of the PV is ahead of some other analog years that match up and because of that instead of a early Jan severe snow storm, such as what happened a few years ago, we might get pattern in the third week of December after the warm up. Total speculation of course. That speculation of course takes into view the - NAO in December as you mentioned. Also, read in the winter of 02-03 we had a SSWE , I never knew that. I know your stance on those and I agree sometimes they mess things up for us. Meanwhile you hear stories on the media that cattle and livestock froze as they stood in parts of Siberia and other locals because that area took the direct hit from the effects of the SSW. A SSW is like going to AC and thinking you are going to win. ha ... We have had our share lately regarding globally severe generational winter events taking place in the NH. I think the odds this winter will present some crazy stuff going down. Heck, look at Denver recently! Seems the atmosphere is aligning to severe blocks and a convoluted structure. Thanks for your thoughts Bob ! Now that you are back we can rock and roll . Cheers !

I am surprised DT posted this as he loves the Euro, but then again he has a colder winter outlook. In regards to the seasonal as well, wondering what is more difficult for the seasonal models to predict, the precip tendencies or the temps ? I would imagine one is related to the other, and both could be difficult to forecast. The signal for precip has been there along the East Coast. Also, still reading things about the NAO for Dec. As @C.A.P.E. posted. Hearing the spread for a +NAO in December has been reduced. Looks like Jan has the greatest indication of a positive NAO from some sources and hence has strongly shifted . This entire sequence of events is remarkable in itself because if a forecaster can call the turning point of the NAO correctly , or the mild period coming up that can make his or her seasonal forecast golden. Maybe in the NE , including our region, we get the NAO to go negative in December ( still awaiting on HM's call of a more so negative NAO later in month ) That might help if we lose the Pac. If we get the - NAO in December does it then last until early Jan 20? If so, then maybe the Pac improves and lessens the need for the -NAO in Jan . Honestly, if the Pac is as good as it seems like it wants to be this season, well we will not need the help of a -NAO as much . Some here are more interested in the rises and falls of the NAO versus a continuous trip well above neutral. These relates to possible storm periods. All these things enter the picture as to how the month of December, Jan and Feb will go. Interesting times ahead. For every action there is a reaction. Call the first action correctly and then you might be more likely to call the next couple months correctly. I see some professional forecasters are still waiting to release their seasonal forecasts. Why ? I think they are again searching for the sequence and timing the evolution of the current pattern, and the reaction after this anomalous cold period coming up. It is not very easy at all.

This conversation is too good to pass up . Webb makes a good reasoning for us to have a warm December and if we get the ENSO 1.2 to warm well it could get ugly. For every action there is a reaction. @bamwxcom · 41m Replying to @webberweather Things are a lot different this year though. I don’t think we’re looking at the traditional Dec torch. Reasoning is winded but just looking at the PV alone, tropical forcing and QBO/solar cob argues this year has legit chances at atleast slightly colder than normal. BAMWX @bamwxcom· 38m No denying the risk and general climo of course but if I were to bet against all that it would be this year. If ENSO 1.2 can stay cool that will help too along with generally -AAM. That’s our idea atleast hope all is well! -Michael Eric Webb @webberweather· 35m Oddly enough, when you remove the strong NINOs w/ huge NINO 1-2 anoms from that subset, the warm signal gets stronger in Dec. I have a hunch we're probably going to hit a brick wall at some pt once the tropical forcing shifts back into the Indian Ocean. http://atmos.albany.edu/facstaff/roundy/waves/RMMphasecompslp500ht.html… BAMWX @bamwxcom· 32m That is certainly interesting. The correlations since 2000 argue an Eastern Us Trough. The EPS/CFS weeklies also stall the MJO in 8-1-2 largely for DEC. If we torch this year I think it may never be possible to get cold in DEC again Eric Webb @webberweather· 24m MJO phases 8-1-2 are cold at lag = 0 in the east-central US, but w/ positive lag in NDJ, we're often mild or torching. I also have reservations about NINO 1-2 staying negative for too much longer. Eric Webb @webberweather ·22m Interesting forecast nonetheless, I hope I'm wrong because I've gotten completely sick & tired of warm Decembers around here, 8 in a row and counting in NC.

Brilliant ! Bring on the ice age baby ! Its about time Snow Miser gets his damn revenge !

Well now, I see HM mentioned the rubber band theory. I know he reads these boards. I also know for a fact Joel Myers from Accu Weather really did talk about this as a theory way back in the day. Not sure if HM's post means a moderation and change in the weather is a natural process, or whether he believes we can continue cold, or simply the most obvious might be there is no real support for the rubber band theory. Who the heck knows sometimes with Anthony. But, I love his insights ! I imagine eventually a pattern runs its course.

Maybe even the South gets involved. Goes to show you the extent and degree of the cold air mass. However, as Webb mentions, it is still early November, and what is a week among friends.

@poolz1 So much to look at these days, very exciting times. The Strat takes a back seat to sensible weather and real time events but this is worth mentioning. Speculation on my part, but maybe this either decreases any moderation period ( even though the outcome is uncertain and lag period as well ) and potentially increases risk of more significant weather events here. As Tip in NE forum mentioned any strat helped - AO outcome may simply get lost in a season of naturally occurring -AO tendencies. So far, so good.