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Surreal look at sunrise with crisp Fall like air, yet a milky, smoky sky above. Temp at a remarkable 47 degrees here at 630 AM. What a quick turn around from just a couple weeks ago.

Where have we seen this before. Will be interesting to observe and speculate on the late Fall implications, in conjunction with SST forcing.

Seems like a bottom 2 percentile - EPO is possibly within reach, if so, very remarkable for September post 1948 dataset. .

JMA for next 3 months. If the Nina's most significant measured drop occurs in the period late October to early December, with a possible lag effect , December could indeed be a cold month in the East. Followed by the real winter pattern of warmth dependent on other factors of course. Still feel the positioning on the High pressure in the Pacific will be the driver, and any appearence of HL blocking. GLoSea mean may indeed be skewed. Also as HM stated the model may have sniffed out the extreme + IOD last winter as the driver to little if any NAO and HL blocking during the 19=20 winter. This year is the IOD is opposite, so what to expect is uncertain in my opinion. As mentioned previously, the poleward High and positioning, in a Nina with a + QBO as Griteater mentioned may have a role in our weather. The sample size has to be considered.

I have seen neutral, Nino and Nina comparison snowfall scatter plots for December through February in the Northern Mid Atlantic which shows we tend to achieve the highest snowfall in a moderate to even skewed stronger Nino. Possibly, as you mentioned, in a Northern stream dominated Nina and dependent on where the cool anomalies are located in the Pacific the temp profile in our area versus a Nino may be colder. The image itself lends to confusion and has little value if you ask me. Just as all Ninos are not the same, the same can be said of Ninas. Of course, as mentioned here previously you really need the establishment of NAO and HL blocking for true winter block buster events in a Nina background state.

ALL IN

I have mentioned this before, along with various posts by bluewave. Anthony has an entire series of posts on this. And without a doubt this trend continues. The focus, well the enhanced area of higher heights near the East Coast between May and October during the most recent 10 year period.

Nice work by HM and cool animation

A little more detail From MH AFD .NEAR TERM /UNTIL 6 PM THIS EVENING/... The band of showers associated with the frontal wave, which has lingered over central Delmarva and far southern NJ the last few hours, should push offshore shortly. The cold front which has only made slow southward progress (as these weaker fronts often do) overnight will accelerate southward this morning away from the area. High Pressure building in behind the front over the Great Lakes will foster a dry N-NE flow over the area with dewpoints steadily dropping N-S through the day. Can`t rule out a few showers over the far south this morning (closer to the convergence zone and the better moisture) but guidance has trended more aggressive in drying us out, so confined mentionable PoPs to southern NJ and southern Delmarva.

As the day progresses according to the AFD from Mount Holly . Your area first then me later .

The GloSea5 did well last year. However, to me that means little for this winter.

The morning Mount Holly AFD commented there was better agreement between the Euro and the GFS overnight, and that the front washes away as it nears us Sunday, and the threat of excessive rainfall on Sunday has diminished. Sunday may indeed be dry.

As many here already know, the QBO is currently positive and looks to continue to become more so in the months ahead. There is some research that points out a tendency for a more poleward based and oriented North Pacific Ridge during +QBO winters. HM mentioned that, along with a couple other mets as well. @griteater recently mentioned it too in a detailed and revealing post. I found it so interesting as to share it here. Nice job with this ! Here is the post below : . The QBO is utilized in various ways with respect to seasonal forecasting, but IMO, it's best use with winter forecasting is not so much with the AO/NAO, but rather, with the configuration of the North Pacific High/Ridge that is common during La Nina winters. A North Pacific ridge is almost certain to be present in the mean pattern during Cool ENSO / La Nina winters when the Jul-Oct averaged AAM is negative (which has been the case thus far for Jul-early Sep). Anthony Masiello's findings from 2012 showed that more poleward north pacific ridges were favored during +QBO winters, while north pacific ridges that were suppressed to the south were more favored during -QBO winters. A key element here is that the designation of the QBO for this purpose was in the lower stratosphere (roughly Nov-Feb averaged at 45mb) as opposed to the typical level used with QBO analysis which is at 30mb. While the QBO began to behave much more erratic than normal at the first part of 2020, it appears to have resumed with a more typical progression as the positive QBO has more firmly established itself in recent months in the middle stratosphere and descending into the lower stratosphere. For the upcoming winter, I would anticipate the QBO to average positive for Nov-Feb averaged at 45mb - most similar to the winter of 2010-2011 when compared to other cool ENSO winters. See QBO Charts: NASA QBO Chart Free Univ of Berlin QBO Chart Below is a list of what I have for the last 11 La Nina winters that followed El Nino, along with the Nov-Feb avg 45mb QBO, then the placement of the north pacific ridge averaged for Dec-Mar. La Nina Winter That Followed El Nino Winter / Jan-Feb avg QBO at 45mb / Placement of North Pacific Ridge avg for Dec-Mar 2010-2011 / Positive QBO / north/poleward north pacific ridge (specifically, displaced to the NW) 2007-2008 / Negative QBO / south/suppressed north pacific ridge (specifically, displaced to the SW) 2005-2006 / Negative QBO / south/suppressed north pacific ridge (specifically, displaced to the SW) 1998-1999 / Negative QBO / south/suppressed north pacific ridge (specifically, displaced to the SW) 1995-1996 / Positive QBO / north/poleward north pacific ridge (specifically, displaced to the NW) 1988-1989 / Positive QBO / north/poleward north pacific ridge (specifically, displaced to the NE) 1983-1984 / Neutral QBO / no clear distinction overall in the north pacific 1973-1974 / Positive QBO / north/poleward north pacific ridge (specifically, displaced to the NW) 1970-1971 / Negative QBO / north/poleward north pacific ridge (specifically, displaced to the NW) 1964-1965 / Positive QBO / north/poleward north pacific ridge (specifically, displaced to the NW) 1954-1955 / Negative QBO / south/suppressed north pacific ridge (specifically, displaced to the SW) Of the 11 winters, the only one that didn't follow the QBO/North Pacific Ridge placement theory was the winter of 1970-1971. Here are 500mb Height / U.S. Temperature composites of the Positive QBO winters from the list: And here are 500mb Height / U.S. Temperature composites of the Negative QBO winters from the list (I left off the 70-71 winter): Clearly, the Positive QBO composite with the more poleward north pacific ridge offers more potential for cold air intrusion into the lower 48 east of the Rockies compared with the Negative QBO composite. One other thing to look for is the Oct-Nov 500mb pattern over the NE Pacific / Alaska / NW Canada. Winters with a more poleward north pacific ridge tend to be absent of negative height anomalies in the Bering Sea, Alaska, and NW Canada during Oct-Nov....while, winters with a more southward displaced north pacific ridge tend to contain solid negative height anomalies in the eastern Gulf of Alaska extending up into portions of the Bering Sea, Alaska, and/or NW Canada. Bottom Line: I would expect the upcoming winter to exhibit a more poleward north pacific ridge in the mean pattern as long as: 1) the QBO progression continues in a more typical manner as seen in the past few months, and 2) the Oct-Nov averaged 500mb pattern doesn't contain negative height anomalies in the eastern Gulf of Alaska extending up into portions of the Bering Sea, Alaska, and/or NW Canada

Appears the modeled December to February NMME precip forecast closely resembles that of a typical Nina.

High dew points set to return later this week. I imagine a sustained cooler pattern may not manifest itself until later in the month, or beyond.

Might get a glimpse into the boreal winter pattern and outcomes during the end of Sept and early October according tho Ben.

The Nina winter of 95-96, as you mentioned was very unusual. We had cold air and coinciding active systems, producing an abundance of snowfall. Not your so called typical Nina by any means. Currently this past decade, and even more so the last 5 years summer blocking has manifested and when the winter months evolve the previous blocking from the summer and Fall diminishes, and even disappears. The last couple winters had the AO and the NAO go weeks on end in the positive phase. Snow advance, overall NH snow cover, and November blocking that some had used to forecast winter blocking ahead never took hold. The various cause have been discussed here. Two years in a row we had record high NH snow cover only to suffer January reversals that were sudden and unrecoverable from. Simply though it appears to evolve around the Hadley cell, the basin wide Pacific warmth, especially in the far SW Pacific, the record setting fast Pac jet, and recently you have to contemplate the strange gyrations of the QBO. Things were never in sync to produce extended cold during the last two winters. I would think unless we achieve some intervals of moderate blocking in the HL and help from the extinct winter - NAO we face serious obstacles in achieving even climo snowfall during the 20-21 winter season.

Data...... . more data ..... somewhere among all these model runs there has to be a fantasy snowstorm

Totally agree. However, a colder than normal winter month will occur here eventually. Whether by volcanic eruption on a massive scale, or a simple serendipitous event.

Came across some posts ( research ), maybe BAMMWX, that alluded to a July and August -AO average correlates into a warm December in the East. Eh, whats new.

What ? No way !!!! I don't believe it, unless they hacked Isotherm's formula.

Just pointing out two contributors that might be favorable. But honestly, the correlation is not strong and we are currently out of sync with things that use to work, or could be used in a analog set, or at the least, had exhibited some tendencies to be pro cold for our area versus warm. Challenges continue to mount for useful winter seasonal forecasts.

Speaking of Nina odds. A post by Don S yesterday below. If you are wondering today's SOI is + 22.40 Seems to me a good bet we get some sort of Nina developing by Fall. The one thing that interests me is the backdrop of the solar minimum. And, the eventual outcome of the QBO in Dec . and early winter. < Today, the SOI was +25.73, which was its highest figure since October 14, 2018. In all three August cases when the SOI rose to +25.00 or above and the August ENSO Region 1+2 anomaly was -0.75C or below, winter saw a La Niña. The most recent such case was August 2010. >

I know I read a couple posts by HM on the QBO behavior during the past 6 months, and even recall some insights as well from Dr Amy Butler. Strange year so far for the QBO for sure. Good luck to those whom want to put out a winter forecast for 20/21. I would say the odds of discovering the correct winter drivers at about 33 %. Those who love the warm train might go climo ( 1990 - 2019 ) + 2 degrees. Those cold and snow weenies better hope for a 95-96 repeat. Sure we can get a cold snow event but difficult to see cold lock in with the same issues re-appearing such as the enhanced fast Pac jet and difficulties in achieving properly timed HL blocking ( or any blocking for that matter) along with the elusive -NAO. Speaking of stratospheric oddities.

@psuhoffman Good points on the post above. Analogs post 2010 have become useless to a degree. And, since 2015 you can probably even reinforce that notion with the Super Nino ( residual ocean warming , etc ) and add to that the recent ocean heat waves taking place. A somewhat newer phenomenon. I see even the great Don Sutherland has added something fitting and new to his weather summaries and look ahead monthly forecasts/stats. PSU , see here ( bolded ) from Don's recent post. Since 1990, there have been 11 La Niña events, 6 of which followed an El Niño winter. 10/11 (91%) case saw warmer than normal September. All 6 following an El Niño winter were warmer than normal. September mean temperatures for New York City for those cases were: 11 cases: 69.9°; Subset of 6 cases: 70.8°; Entire 1990-2019 period: 69.0°. The September mean temperature for all La Niña and neutral-cool cases following an El Niño winter (1950-2019: n=13) was 69.9°. Overall, the evolution of ENSO, along with the observed ongoing monthly warming (1.6°/decade in NYC and 1.5°/decade in the Northeast Region during September 1990-2019), favors a warmer than normal September. He is incorporating the new climate warming into his summary, very interesting. For me personally , I see no end to the issues in the Pac this winter that have haunted us the past 3 winters. So many elements in addition to the Pac are negatives for a cold and snowy winter in our part of the world.