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Certainly has been a tendency for hotter summers it seems lately, although I wonder the data set regarding Don's research. Are we to possible expect different outcomes this time around due to changes in summer blocking and changes in the base state? Hard to argue that the Atlantic 's warm SSTs are not going to be a factor in the summer and in the early Fall this year. We have not knocked down those ocean temps much this winter at all. I can see implications possibly for the upcoming Hurricane season. Touching on blocking in the NAO domain , in hindsight those who expressed concern about the record - NAO back in the late spring and summer were correct. When the NAO flipped to positive it remained there for about 95 % of the winter beginning on December 1 st.

Wonder whether there is research on the SPV and the TPV in winters such as 2020 and what the next winter evolved into? If the Pac has any influence on the vortex in terms of precursor patterns and weakening, etc. are we looking at stronger winter vortex setting up in future winters ? Seems that although up North has been cold, not so sure this will carry over to any long term benefit though. Certainly the high speed jet circling the NH is remarkable, this image is a great representation. Again, what will be the spill over effects be for the early summer? Some modeling is indicating a somewhat warmer spring. But, but beyond the seasonal vortex weakening and changing wavelengths maybe a more normal summer might await us.

Of the hundreds of snow maps posted during this winter only about .000000001 % ever looked good for us. Snow maps in the medium range and long range have proven to be total BS this winter. Meanwhile .....

You think the new regime that might favor more - NAO gets underway next winter ? Or, is the lag effect longer in your opinion?

Believe @Isotherm went with below average seasonal snowfall, with any significant snowfall in late Feb and March. What about Kieth Allen 's forecast? Thought he went super warm and little snow?

Conflicting signals for spring . We are in a new base state, and to a degree the outcomes for the spring might be surprising, for that matter maybe even the early summer as well. This record +AO and relentless powerful vortex shows no sign in weakening. Another record + push may occur shortly with the AO. Fascinating weather in terms of extremes at the HL. The 12 to 18 month repeating pattern of hyper jet, Pac ridge and little winter blocking continues. The remarkable seasonal associations of using both the the +PNA and the -AO to forecast snowfall so far have been flawless. Never even have to look at a model when you have such an extreme +AO , and such a long duration - PNA combined with a very poor NAM state and little to any - NAO episodes.

I believe SD. It has during the past 6 weeks gyrated significantly between neutral and highly positive. Just as the EPO has been forecasted several times since mid December to go negative only to adjust to positive or neutral, so has the AO reverted back to highly positive or positive after modeling indicated it was going to go back to negative territory.

Have you done any research on the summers that follow winters similar to this one bluewave?

The IOD is not going super negative quickly, that sure is evident here. Actually you could say a stall last two weeks. 20191021,20191027,2.06 20191028,20191103,2.01 20191104,20191110,1.67 20191111,20191117,1.58 20191118,20191124,1.36 20191125,20191201,1.14 20191202,20191208,0.86 20191209,20191215,0.82 20191216,20191222,0.56 20191223,20191229,0.31 20191230,20200105,0.17 20200106,20200112,0.34 20200113,20200119,0.12 20200120,20200126,-0.01 20200127,20200202,-0.06 20200203,20200209,-0.06

Crazy things continue down under and in near by regions. Maybe the lingering effects of the record + IOD.

As you know there have been a few months that have started firmly below average , up to - 8 degrees negative departures, but the warm-ups arrive and the negatives are wiped away. Take for example this past December . Another observation that last decade trend of colder early Decembers followed by the post 12/20 warm-up. Also, a heads up that any positive you see in November and even early December means nothing for the winter ahead. At least for the last two years. Changing signals and false analogs. Just random speculation but many were faked out by this late Fall and early winter. We learn and adjust for next year.

Certainly a plausible scenario. Please, can we get some lower minimums at night, less humid would be great too, so less lawn fungus.

Probable guess, during the + PDO / - EPO driven winter of 2014 - 15 , when Lakes froze, it was a remarkable cold period. I might be off a year but I think one of the months was firmly below normal during met winter.

That might be correct. I have to check.

This year is rather remarkable in terms of the consistent trough in the area of Alaska. Some stations in the Yukon and NW Canada setting some records for the coldest weather in many years. Meanwhile, I believe two days ago, another record set for the jet stream, this time over Green Bay. No changes on the horizon at all, if anything warmer risks more likely I think and a overall warmer March. Also noticed the AO ready for another huge climb up after the recent record over over +6 SD. The recent trends regarding the warmer SSTs in the Eastern Pac also foretell of a warmer March , in addition to the AO modeling. However rolled over the warmer March gives way to a colder April. Wondering too about the summer , as I am hearing varying opinions about the summer weather pattern in the East, ranging from little precip and extreme heat to a cooler summer. I can not even remember the last month around here that averaged below normal.

That would fit Isotherms's window almost perfectly. We will see.

I would enjoy some snow in early to mid March before we ramp up to warmer weather. Maybe we can keep the bugs at bay for a while as well. It certainly is not impossible we get that window you are referring too. Wavelengths certainly may enter the picture as we enter the first week of March. Time some cold with moisture and bingo. Near Atlanta did it recently, so all options are still on the table.

Remarkable, but fleeting, right near the 20th of the month. Once again we see a good chance at a rather intense cold shot later next week, timed almost perfectly with previous months this winter. The vortex vacillation seems to continue the pattern. Another theme this winter at times is the variability and sudden swing in temps including your favorite warm wet and then cold and dry. Cold and dry in this back ground state is typically between 36 to at most 72 hours.

Well now

I wish I was more hopeful, because it will take a lot to break away form this regime, or as Ventrice described it, as a anti-blocking pattern. The jets are zipping along. Huge record breaking event also on the way this weekend in the North Atlantic. Wow

It certainly appears the hope for a back loaded winter are all but gone. Think we have a warmer March along with Don's ideas ( below ) and I feel the opportunity for any meaningful snowfall in March is very, very low. From Don S. morning post today : << Morning thoughts... While attention has been fixed on the record-setting AO+ regime that saw the AO reach a preliminary all-time record of +6.342, another development that has occurred in the eastern Pacific has increased the probability of a warmer than normal March. That development also suggests that any snowfall in the Middle Atlantic region after February could be limited. ENSO Region 1+2 has warmed dramatically over the past two weeks. During the week centered around January 22, the ENSO Region 1+2 anomaly was -0.2°C and for January 2020 it was -0.04°C. During the most recent period (week centered around February 5), that anomaly had risen to +0.8°C. Both the 2/12/2020 0z EPS and GEFS suggest that the AO will return to extremely positive values near or above +4.000 around February 20. In addtion, based on the outcomes following the 1989 and 1990 super AO+ regimes in February and assuming a secondary peak at extremely positive values (+4.000 or above) around February 20 +/- a few days, March will likely begin with a noted absence of blocking in the AO+ region. The evolution of the February AO+ regime would argue that the AO would likely remain positive for much of March. During the 1981-2019 period, there were seven cases where the February ENSO Region 1+2 anomaly increased by +0.5° over the January average: 1989, 1991, 2002, 2006, 2008, 2011, and 2012. Five (71%) of those cases had an AO+ to end February and start March: 1989, 2002, 2008, 2011, and 2012. The March composite 500 mb and temperature anomalies for those five cases are below: Mean March-April snowfall for New York City for those five cases was 0.7" (skewed by 2.5" in March-April, 1989) and 0.5" in Philadelphia (skewed by 2.4" in March-April 1989). >

Impressive + NAO and wide ranging warmth across parts of the NH. Meanwhile...........

The 20th of the month has been a colder time for the past several months and this occurs in what some mention as a vacillation of the vortex which according to HM happens in stronger vortex winters. This time of the month coming up may once again have minor interest. The last three times it happened cold ejected Southward but did not time well with moisture. Not sure this time is any different . Speculation on my part maybe the GEFS is wrong and the current NAM state is more hostile than in November, and December and even Jan. So, maybe the cycle does not duplicate near the 20 th. Of note as well is the GFS:

Makes sense, I know Bob pointed out a few days ago how the control seems to regularly spit out snow storms for our area. Just interesting to note. Another cool seasonal repeating phenomenon, and I think this goes back to last winter as well, the under modeled SE ridge and expansive WAR and how storms always seem to trend NW in time and the scarcity, for the most part, of suppressed systems. Repeating theme, 20 % coastal huger, 70 % cutter and at times a suppressed system 10 % . % are estimated on my part. The seasonal models forecasting of an active STJ was correct but the lack of cold and blocking had always guaranteed rain versus snow. Lastly I believe a record sub sonic flight was set this weekend at an average speed of over 800 mph shaving 1 hour and 17 minutes off a flight leaving maybe NYC and going across the pond. That is remarkable, sorry I can not recall the exact departure and arrival locations. Next up is watching the Atlantic Basin ahead of the hurricane season and the East Coast SST profile. Might be an early beach season if Spring is not cold.

Pretty much the same back ground state since late December, meanwhile the research about the warm West Pac and its role on super charging the jet continues, and is making me a believer. Routine records being set for jet speed across the NH while the vortex remains coupled and strong. No way to weaken it in the background state we are in. March looks less hopeful now, and I feel it averages 1 to 2 degrees above normal . Also, learned during this winter not to trust at all the GEFS when it comes to vortex weakening, and the CFS is totally unreliable and useless. Also, many false hopes could have been avoided if the new GFS was not rushed into action, as it still had a very serious issue with temps and because of that false hope digital snow forecasts galore. Plus, the Euro Control portrays snowfall a few times this winter in the Northern Mid Atlantic when it was not supported by its ensembles or the OP.