Ralph Wiggum

18z GEFS has BN 2m temps thru the entire 384 hr run for the area. At 500mb it also has a respectable look with the WAR/N Atl ridge repeatedly feeding the -AO and NAO region. Aleutian low persists with subsequent ridging along the West coast. All we can ask for at this time as things progress thru late fall. The progression and tendencies of the main teleconnections which affect our apparent weather during the winter month appear favorable for now anyway.

The chart below seems to fit in well with my thoughts as we progress into late Nov. Caveat moving forward is whether this will be a recurring theme this DJF or a flash in the pan with a pattern rollover in Dec. We will know in a few weeks:

PV splitting with the more dominant lobe over Siberia and another slightly weaker lobe near Hudson Bay would not be a bad thing AT ALL. That is IF that scenario in fact occurs. One dominant TPV anchored over the Arctic circle does little good. Nor does the PV remaining in tact and propagating towards Siberia. We also in turn probably dont want to see the main PV anchor itself over or South of Hudson Bay overwhelming the area with cold like a Nina. Looking at the SPV and TPV progs along with SST data in the N Atl, the current state/forecast of ENSO, and low but slowly increasing (forecast) solar activity, I am a proponent of where the overall pattern, especially irt the N Pole, N Atl,and HL Blocking potential is headed over the next several weeks into the New Year.

I'm confident the PV gets a beat down and splits, but not because the GFS says so. I am using solar data as well as SSTs in the N Atl, hemispheric snow coverage, and simplistic recent tendencies. Guess we wait and see what happens and if it is something that might show continuation through late Nov into Dec and down the line.

The interesting part is the SPV seems to be strengthening BUT the TPV is forecast to take a heck of a beating and split in 2 if not 3 by 240 hours. That bubble ridge over the N Atl at the 10hPa layer is wreaking havoc on the forecasting of PV imho.

@Newman Great post! You touched on several of the indices/oscillation teleconnections which I purposely avoided lol. The QBO I dont believe we can count on to determine HL blocking timing and/or placement. Many learned this the hard way last year, myself included. The PAC has more times than not failed us recently BUT we have still managed to get the cold thanks almost solely to the EPO ridge. As you said, a Western displaced PNA/EPO ridge will give many of us fits this winter....but based on progression over recent weeks, things appear headed in the proper direction. The appearance of the Aleutian low after a period of HL blocking over that region is a refreshing and welcoming signal. I've actually been more focused on the Atlantic side in recent years...more specifically the WAR and it's influence or lack thereof on the NAO. Given the state of low solar activity among other factors, the AO should spend a fair amount of time in the neg or neutral territory as we have seen in recent months. This feature is probably the key player on winter weather for you and I as well is the placement/timing of any NAO ridging. Again, it is how the WAR is impacting the NAO which is going to be a key driver once again this season. I'm convinced we get the cold spells (no winter long torch) thanks to the EPO and we will have the neg AO a portion of the time. We will get a blend of snow, thump to rain, and cold rain this winter. Question is, can we can get the holy trinity (-AO/-NAO/-EPO) to work in unison at any point for the KU? Confidence is higher than normal that this is realized at least once.

Want to begin by stating most of the comments in this outlook and stats are being based off of KDYL and not necessarily KPHL proper unless otherwise noted. Coming off of winter 2018-19 where most areas in and around Philly metro nickel and dimed their way to BN seasonal snowfall totals, winter weather enthusiasts can only hope the coming winter of 2019-2020 will be more of a bounceback season in terms of both seasonal snowfall amounts and quantity of snow per storm. Last season featured a fair amount of chances, but the majority of those turned out to be minor/nuiscance coating to 2" type events with just a couple of 3-6" systems tossed in thanks in part to a transient pattern overall and more fropas than actual storm systems affecting the area. With the ENSO currently in a neutral phase and forecast to remain as such (chance for fluctuations towards weak El Nino) thru spring 2020, major hemispheric impacts should be mainly muted. However, there are tendencies for the East and Northeast US to be colder than normal during these phases. Taking a look upstairs into stratosphere, the SPV appears to be relatively stable with elongation over Asia/Siberia and also into the N Central US with a bubble ridge over the North Atlantic and also over the Bering Sea which are putting a 'squeeze' on the SPV. In response, the TPV is taking some damage and looks to undergo some splitting over the next several weeks with (in general) a piece moving into position near Hudson Bay and another near Siberia. Determining IF the TPV continues to show tendencies to remain split as we delve into the winter month is TBD, but seeing the TPV starting to hint at this in November is never a bad signal. In response to the PV activity, the AO/NAO, which have been hanging around the negative overall since summer will have major implications on apparent weather in our region. With the PV having pressure on it to force splitting and the general temp anomalies during a neutral ENSO/weak nino, chances for severe cold outbreaks, ie lobe of the PV paying a visit, is increased during winter 19/20. Soil moisture is expected to increase over the Mississippi River Valley and into the Southeast over the next several weeks which will help carve out a few different storm tracks, one of which is a suppressed look at times (remember that PV plunge pressing South?), one off of Hatteras NNE/ENE, and the other up the Tennessee Valley and just West or over the I95 corridor. The Clipper will pay a couple of visits this winter as well. Of course there will still be other tracks but the primary ones have been laid out. Solar activity is low and appears to have bottomed out. As 2020 approaches, solar/sunspot activity is expected to slowly increase. Historically, there has been 'some' correlation between the period of least solar activity into the subsequent increase and -NAO/-AO sustainability. The exact reasons 'why' are not quite clear to me as I have not studied this particular facet of forecasting as much as I would like, but it is something that I have noted during my limited research on the subject. The WAR which was a significant factor last winter is still appearing to be a player at times. However, there is something invariably different in this feature and model progs over the past several months. Many LR forecast trends had been showing this feature linking up with a SE Ridge every time it has surfaced. Though as lead times lessened, the WAR has, for the most part, remained separate from any subtropical ridging and has either verified as flattening at times OR actually feeding the -NAO. THIS IS CRITICAL and one of the keys to the winter forecast. If the WAR continues to be the catalyst to aid in development/strengthening of the NAO ridge over Greenland, the chances for a larger than usual winter storm(s) in the Northeast and Northern part of the Mid Atlantic region increase. With that said, there is a higher than normal chance for at least one 10"+ type snowstorm for the area. Without delving too much into detail on the PAC, the development and resurgence of the Aleutian Low has been a welcome feature as has been the split flow off the SW US Coast and a linkage at time from the tropical Pacific across old Mexico and into the Southeast US as it undercuts ridging that is apparent in the PNA region. This is likely in part to the ENSO phase specifically the warning recently in the subtropical Eastern PAC regions (weak Nino tease?). The EPO ridge has also been showing itself, and although displaced at times, may become more of a player aiding in CPF emerging and funneling into the Plains then spilling East. So, while some may read this and assume wow, he's all-in on an epic winter, that is hardly the case at all right now. There are many features that look very promising, BUT there are also features that counter those positives such as location, location, location. If the PV split or continues to be pinched/squeezed who is to say exactly where it will go as the pattern becomes convoluted? It could easily dive into the Western Plains as much as it may become displaced over the OV. PV could also fight back and remain one organized entity anchored over the North Pole which would put a wrench in my thoughts. Also, the storm track tendencies mentioned do not assume cut and dry frozen precip every time. And what's to say a PAC firehose won't develop at times like we struggled with last winter? I could go on and on about what ifs, but suffice it to say every forecast, especially seasonal forecasts, have nuances that can significantly affect the outcome. This is no different. With all of this said, my thoughts are for near normal to just above normal snowfall for my forecast area which for Doylestown is right around 30". I dont do the monthly breakdowns as that is just something I've never gotten into. I really cant say with any confidence whether this will be a front loaded or back loaded type of winter (or normal balance). Though if going by sheer pattern evolution, I would be more prone to say December will produce this year. Provided things dont collapse there should be a fair amount of tracking opportunities early. So not the winter to end all winters but certainly not a dud either. Chances for HL blocking are increased which should increase the likelihood of at least one major event (KU??). PV will drop down and give a period(s) of severe cold but there should be some balance with the pattern relaxing and moderating between episodes.

Has the Panic Room opened for free tours yet before the Dec 1 meteorological winter Grand Opening? @WxWatcher007

12th/13th 'event' has all the ear markings of a mid range threat in a relatively progressive pattern that ends up being one consolidated lo farther N than progged with just a fropa for many. Could be wrong but has alot of resemblance to several systems last winter that never materialized.

GEPS is flat, weak sauce, and far enough off the coast to essentially be a nonfactor

But the GGEM shifted S and E

If this were DJF many would be reading the signs and sticking a fork in this one. Whaddya think.....95% of the time we see this, these systems never trend back the right way?

The usual trends have begun....congrats New England and far interior lol. Joking of course but funny to see the jump from the bullseye SE of us now into NE.

GEFS and GEPS close to the coast. EPS oddly enough is the farthest SE and off the coast. Not a bad place to be. Would rather this be 3 or 4 weeks from not but this can definitely happen especially with a fresh cold arctic air intrusion as modeled.

Congrats on next week. Every medium range model has you getting measurable snow now. NJ in the crosshairs less than a week out. What could possibly go wrong?

Front comes thru Thursday maybe some flakes on the backside especially far NW zones. Potential still showing for something around the 12th/13th. Worth keeping an eye on anyway since it could provide the first flakes of the season for parts of the metro area. EpS has been solid on the signal. Lost the bomb that it was showing but overall has a nice look with energy rounding a trof in the East and a wave off the coast throwing back some moisture into a fresh cold air mass. GEFS is trending in the right direction. I am posting the mslp trends over the past 4 runs as well as the 500mb anomaly maps. Note the pna ridge firing out west with each run.

Depends on who you asked I guess.

EPS and GEFS fairly similar irt key features during this period. Ridge bridge over top is nice, PV over the GL with trof along EC, ridging out West (PNA and EPO). Would like to see the WAR start feeding the NAO as we head later into the fall and become a recurring progression.

But did you see the BOMB on the Euro just a bit too far off the coast around the 13th? Something is going down during that period. Same time frame the GFS was dropping Barney's PV into the region for a few runs. And yes, other guidance like the GFS op has a storm but not nearly as organized/consolidated as the Euro. Certainly worth a look over the next several days....see if it has legs.

12z Euro with a weenie run for early/mid November standards.

Euro is slightly more amped digs the trof just a bit more. GFS really isnt that far off tbh. Euro is right in between the eps and gfs OP which if this were 4 weeks from now most of us would be greatly intrigued. Not a bad place to be. Again, something to finally tease us that isnt just the para gfs.

Top is the Euro, middle is the EPS, bottom is GFS:

Some interesting developments on the horizon. Both the GFS and Euro are rather close to something late week (Friday?) with a lp area sliding South and unseasonably cold air hanging around. Would likely favor those climo and elevated areas but who knows? Something to tease us. Then the GFS is showing a chunk of the PV visiting the OV and Northeast around the 13th with some mood flakes (maybe something more?). Again, some things to keep us entertained at least.

New GFS has been great for head fakes thus far anyway: