January 2020 Mid/Long Term Discussion

[Weather Will]

0z EPS probability of 3 inches or more.  Most of the probability in DMV is associated with days 10-15.

[MJO812]

3 hours ago, Ji said:

6 hours ago, psuhoffman said:

It’s ok. The 50/50 is fine. The blocking is fine. But the trough cuts off over Colorado then lifts up near Chicago. That’s the issue. There is cold in front available if it took a good track. 

Euro says no

Check out the gfs

[Ralph Wiggum]

35 minutes ago, Weather Will said:

0z EPS probability of 3 inches or more.  Most of the probability in DMV is associated with days 10-15.

Isnt it 99% always day 10+ though? 

[Weather Will]

10 minutes ago, Ralph Wiggum said:

Isnt it 99% always day 10+ though? 

Seems that way.  I like the probability maps because it helps me to see if there are any trends developing Or not as the case this winter for DMV snow threat.

[Ralph Wiggum]

This day 10 threat is closely resembling the system for this weekend at roughly the same lead time. Guidance showed ridging moving across S Central Canada with an ULL moving underneath. The ridging kept looking stronger for a bit and I remember posting how the surface low couldnt cut. Same setup day 10 now. Someone will assuredly reply how this setup is different and it is contingent on the 50/50 and the ridging I mentioned and that a minor adjustment puts us all in the game. And while I agree, there is the argument that a minor adjustment the other way can take us right out of the game too. In any event, the storm track and base pattern will be the same here as others recently. We've seen this before where the next one looks better, the one after that looks better. Not trying to deb just making my case why I think the long lead system is going to end up not working as we would like. Recent history and very similar setups say primary moves near the GL and secondary develops just a smidge too late. Timing and placement of key features are just a hair off this season for whatever reason. I hope we trend differently but I cant go against what we've seen already.....maybe this can somehow buck the trend and be "the one". Things look ok now on the ens but again, to have this hold or improve over 10 days this season is a tall order.

[CAPE]

2 hours ago, Weather Will said:

0z EPS probability of 3 inches or more.  Most of the probability in DMV is associated with days 10-15.

All these maps do is remind me that I live 150 miles too far south for snow 90% of the time.

[psuhoffman]

@Ralph Wiggum

the longwave pattern is completely different. It’s in transition now as the central pac ridge that has been the main driver begins to shift up through the epo domain and eventually ends up centered in central Canada.

Just like late December was a different pattern from now. Both were bad patterns for snow here. If all you do is look out you’re window to judge then they might seem like the same pattern. But ask anyone in the pac NW and they will tell you how different the last 2 weeks were from the last 2 weeks of December!  

We can fail in lots of different ways because we are not in a location where snow comes easy. It’s not the normal. It’s an anomaly that only happens when we get several variables to line up favorably and even then we need luck. 

One commonality between this past pattern and the coming one is a positive AO. That going to make getting snow an uphill battle here even with other variables shifting around. 

[jaydreb]

6z GEFS not supportive of the Day 9–10 event.  Maybe 1 or 2 members have a hit of some sort, the rest have nothing or rain.  It ain’t pretty right now for snow chances.  

 

[Orangeburgwx]

[mention=4298]Ralph Wiggum[/mention]
the longwave pattern is completely different. It’s in transition now as the central pac ridge that has been the main driver begins to shift up through the epo domain and eventually ends up centered in central Canada.
Just like late December was a different pattern from now. Both were bad patterns for snow here. If all you do is look out you’re window to judge then they might seem like the same pattern. But ask anyone in the pac NW and they will tell you how different the last 2 weeks were from the last 2 weeks of December!  
We can fail in lots of different ways because we are not in a location where snow comes easy. It’s not the normal. It’s an anomaly that only happens when we get several variables to line up favorably and even then we need luck. 
[bold]One commonality between this past pattern and the coming one is a positive AO.[/bold] That going to make getting snow an uphill battle here even with other variables shifting around. 

I went and looked at the latest GFS 14 day interconnections

EPO: strongly positive (of course..)
PNA: Goes positive (bonus)
NAO: dips negative around the 26th
AO: dips slightly negative around the 29th

Get the EPO to tank and we will be in good standing


Sent from my LML212VL using Tapatalk

[CAPE]

15 minutes ago, jaydreb said:

6z GEFS not supportive of the Day 9–10 event.  Maybe 1 or 2 members have a hit of some sort, the rest have nothing or rain.  It ain’t pretty right now for snow chances.  

 

12z GEFS yesterday had an impressive signal for snow for the 25th-30th period. Since then it has deteriorated significantly. The general pattern being advertised is pretty decent overall, but there are little "flaws" showing that shift around between model cycles. 

[Ralph Wiggum]

56 minutes ago, Orangeburgwx said:

 

 

I went and looked at the latest GFS 14 day interconnections

EPO: strongly positive (of course..)
PNA: Goes positive (bonus)
NAO: dips negative around the 26th
AO: dips slightly negative around the 29th

Get the EPO to tank and we will be in good standing


Sent from my LML212VL using Tapatalk
 

 

Dont use the GFS op for forecasting LR teleconnections would be the best advice anyone can offer.

[Ralph Wiggum]

38 minutes ago, C.A.P.E. said:

12z GEFS yesterday had an impressive signal for snow for the 25th-30th period. Since then it has deteriorated significantly. The general pattern being advertised is pretty decent overall, but there are little "flaws" showing that shift around between model cycles. 

It's the see-saw ens pattern we've seen since mid Dec. I have no clue what is causing it but we go 2 days of great looks then swing towards a degrading look then back again in 2 days. And at the end of the day the better looks and 'productive' storm chances are still 10 days+ out.

[CAPE]

Just now, Ralph Wiggum said:

Dont use the GFS op for forecasting LR teleconnections would be the best advice anyone can offer.

I took a peek this morning and the GEFS and EPS both have the AO trending towards neutral, and the NAO going slightly negative. Nothing is locked in up top though, and no signs of a sustained -AO or -NAO.  Look at h5 on the 6z GEFS at the end, and the TPV is over Baffin with a ++NAO look.

[frd]

18 minutes ago, Ralph Wiggum said:

t's the see-saw ens pattern we've seen since mid Dec. I have no clue what is causing it but we go 2 days of great looks then swing towards a degrading look then back again in 2 days. And at the end of the day the better looks and 'productive' storm chances are still 10 days+ out.

This November's head fake, just like November 2018,  was alluring and drew some folks in .

The seasonal models so far are nailing this winter. Too bad they sucked last winter in predicting the epic pattern that did a Pamela Anderson. Bravo so far to Isotherm.

Modeling in the long range this year seems no better than last year in losing favorable patterns. Whether it means the little things that are causing it or larger  scale issues, what matters to me  is that  you can not put any faith in solutions beyond day 6. I know our regional climo sucks for snowfall, but you have to see that there have been some rather large scale busts in patterns in the medium range since November , with incredible swings in the EPS and the GFS.  

 

[frd]

 

If we can get some cold air masses to be present during early Feb, we  will have an active STJ to work with.  However, I can see a lot of ways to lose. Cold air seems to lose out the closer we get to any events so far this season , and sometimes the Pac jet interferes with Western ridging.  But, there is potential, which is better than 70 and sunny on Groundhog's Day.   

 

[frd]

 

A very intense wave breaking cyclonic event next week, wonder the implications for the time period afterwards. Very complex to figure this one out for us. 

 

[psuhoffman]

39 minutes ago, Ralph Wiggum said:

It's the see-saw ens pattern we've seen since mid Dec. I have no clue what is causing it but we go 2 days of great looks then swing towards a degrading look then back again in 2 days. And at the end of the day the better looks and 'productive' storm chances are still 10 days+ out.

You clearly are implying some kind of continuity with the seasonal pattern this year...but in reality we have had none.  The only constant has been consistent change.  So far this winter season we have had 3 very distinct DIFFERENT 2 week patterns.  And we are heading into another 4th different pattern that looks to last...get this.. about 2 weeks, on guidance.  

This pattern

Dec1-15

WAS NOT LIKE THIS PATTERN...

Dec 16-31

WAS NOT LIKE THIS PATTERN...

Jan 1-13

Pattern 1:  The pattern early December was dominated by a favorable EPO ridge but with a very positive NAO.  Had that pattern continued into the core of winter we likely would have done OK.  It's not the best look every but very workable.  But it was a bit too early, we had a few threats and some minor snowfalls during that period but it was too early to really judge its effectiveness as a "snowy" pattern since we don't typically get much snow that early anyways.

Pattern 2: Was dominated by -AO but a AK vortex that lead to a pacific puke airmass overtaking the CONUS.  The Atlantic side was good during this period but the pacific took a dump on us and early in the season its almost impossible to overcome that look in pacific. 

Pattern 3: The worst pattern possible, it's amazing we scored a fluke snowfall (although it was a minor event and those can sneak into ANY pattern with a lot of luck) due to a well timed transient ridge out west... but dominated by a huge central PAC ridge and positive AO/NAO.  This is one of the worst patterns for snow here.

The coming pattern that looks to dominate the next 2 weeks or so looks like this...

Pacific Trough, ridge across Canada (Hudson Bay Ridge) Atlantic Ridge displaced too far south for where we need it... 

This isnt a horrible look...it gives us a MUCH higher chance of a significant snowfall than the last 2 patterns did... (in the cities) but it has warts that could prevent that and right now they are showing on guidance.  I will get into that in my next post.  

 

[psuhoffman]

@Ralph Wiggum

If we break down all the different combinations of patterns...the problem is only like 20% of them are "good for snow" here...and even in one of those "good for snow" patterns we need luck or we can waste it.  The pattern we are going into isnt a "good for snow" pattern...but its not in the "bad for snow" either.  It's kinda a "meh" look... and we sometimes score in those but it will take some things breaking our way.  

If your point is that our odds of a big snow within the next 10 days continues to be low... you are right.  But that would be an accurate statement 95% of the time.  But if you are implying the pattern is not really changing and everything remains the same...that is not accurate.  Different doesn't necessarily mean snow though.  

[frd]

1 minute ago, psuhoffman said:

So far this winter season we have had 3 very distinct DIFFERENT 2 week patterns.  And we are heading into another 4th different pattern that looks to last...get this.. about 2 weeks, on guidance.  

 

Excellent points, goes along what I was thinking about change in general, no one pattern has legs. 

 

[frd]

 

Whether this matters down the road is debatable  , but there does seem to be some indication is a slowing of the zonal winds in the weeks ahead. Not sure how much of that is typical seasonal effects taking hold. ( weakening ) 

Any one know when the new QBO data arrives ?

 

 

[psuhoffman]

53 minutes ago, C.A.P.E. said:

I took a peek this morning and the GEFS and EPS both have the AO trending towards neutral, and the NAO going slightly negative. Nothing is locked in up top though, and no signs of a sustained -AO or -NAO.  Look at h5 on the 6z GEFS at the end, and the TPV is over Baffin with a ++NAO look.

Our fate isnt as dire as some of those snow means indicate.  The guidance across the board did deteriorate wrt the day 10 threat but that is dependent on a single feature...getting a stronger 50/50 to knock down ridging to our northeast... that it could easily trend back on guidance if that one thing changes.  Actually across guidance there was a trend towards squashing that wave because of "too much ridging" up top.  But either way that isnt a high probability right now...but its not completely dead either. 

After that the snow means look pretty ho hum but part of that is due to a scatter shot in the day 11-15.  There are a lot of misses to our south on the GEPS/EPS/GEFS.  Some misses to the north (but not by much) and a few hits.  That scattershot produces a mean that is unimpressive...but is not the same as a similarly unimpressive mean from a consensus that everything will go north of us.  That is a bigger problem and much less likely to change in our favor.  As the pattern day 11-15 gets closer the guidance will converge on where the waves within that period will track and once they do we will see somewhere benefit.  It could end up NC.  It could end up here...it could end up just north of us...but somewhere within that box will likely get snow in that period.  

 

[Ralph Wiggum]

9 minutes ago, frd said:

 

Excellent points, goes along what I was thinking about change in general, no one pattern has legs. 

 

But the pattern concesus no matter what nor how the tellies shift around to change the overall hemispheric look there is almost zero tendency neither this season or last to progress into something that provides meaningful widespread snows. I know parts of this sub had a fluke event 10 days ago but these small windows in between tellie shifts are the only ways we score and even then I would say of the 5 or 6 times the key features transition only 20% of those windows are producing. One of these seasons it will reverse and.the atmosphere will do no wrong. It is just proof again it is so damn hard to get a pattern that produces for more than one of our subs in a particular event. 

[frd]

7 minutes ago, Ralph Wiggum said:

One of these seasons it will reverse and.the atmosphere will do no wrong. It is just proof again it is so damn hard to get a pattern that produces for more than one of our subs in a particular event. 

Of note,  bluewave mentioned this a while back, we have been lacking a Miller A track and even a Benchmark storm(s) in the winter recently . Folks have scored up North but in some unusual ways. The Pac jet the last two years, in varying ways, has interfered with some of our favored windows/threats for us here in the Northern Mid Atlantic, to what degree is debatable, and you can refer to climo, as it just being par for the course.  Some years everything goes right, some not so much.  

[psuhoffman]

After looking over the 3 ensembles overnight... After the day 9/10 threat (that has been covered already) the EPS and GEPS both agree on developing a fairly favorable pattern.  The GEFS is further east with the eastern trough but that could be its bias to press cold too much.  We actually want the trough centered further back. 

We have been in this cycle of 10-15 day patterns with short transitional periods in between since November.  That looks to continue.  The next pattern is starting to show itself as one dominated by a central North American Ridge with the southern Jet undercutting across the  US.  That can work if we can time up a system with a 50/50 low.  It's actually a pretty common look within snow analogs.  It's not a very cold look but get a storm to track right under the blocking ridge and it can work.   But like @C.A.P.E. said right now there are discreet warts showing that prevent that on guidance.  Too much ridging extending to our northeast being the main one.  

I really debated even saying this because I do not want to send this thread off on a tangent... but it's something that I have been kicking around in my head.  There were a LOT of snowstorms in the data set with a look close to what we have coming up.  But they were mostly pretty warm storms...a LOT of storms where we managed to overcome marginal temperatures.  It is not a cold pattern look.  But...looking at some of those storms from the 50's, 60's, 70's, even 80's and 90s....I have to wonder if the atmospheric base state is cold enough right now for that to work.  Without starting a debate about climate change, the fact is the base state is warmer right now...I am not getting into the why or what to do about it debate, there is another thread for that so save it.  And you know who I am talking too.  But would a storm from the 1970s that dropped 8" of heavy wet snow from 1.3 qpf on a day with a high of 35 and a low of 31 even work right now?  And that is kind of the profile of a LOT of the storms in the "Hudson Bay +AO" snow set.  Just a thought... 

As for where we go AFTER this...there are signs again of the pattern starting to shift towards day 15.  Where is unclear though.  There are signs of a trough in the north PAC...where exactly that ends up might be the key.  If that sets up near the Aleutians we might shift into the typical EPO ridge pattern we kind of expected to be setting up this week.  If that presses too far east into North America...we probably get flooded with pac puke unless the NAO flips and there is no sign of that.  Of course phase changes up top tend to happen within 10 days so we probably won't know when its 15 days away.  The MJO is sending conflicting signals in the long range but most of all it seems to be going somewhat dormant after this current wave fades.  But I see no sign of a return to a strong MC signal so that is a positive.  We still have agreement on the long range guidance of an EPO ridge +NAO pattern...but they were advertising that the next 2 weeks and totally missed so how reliable are they at 3-4 weeks?  The only consistent theme this year is variability and a lot of conflicting signals. 

So I guess I am saying I have no freaking clue what happens after this coming 10-14 day pattern.  I wouldn't be shocked if we end up with a favorable look...or end up in another no hope dumpster fire one.  

[psuhoffman]

23 minutes ago, Ralph Wiggum said:

But the pattern concesus no matter what nor how the tellies shift around to change the overall hemispheric look there is almost zero tendency neither this season or last to progress into something that provides meaningful widespread snows. I know parts of this sub had a fluke event 10 days ago but these small windows in between tellie shifts are the only ways we score and even then I would say of the 5 or 6 times the key features transition only 20% of those windows are producing. One of these seasons it will reverse and.the atmosphere will do no wrong. It is just proof again it is so damn hard to get a pattern that produces for more than one of our subs in a particular event. 

about 20% of the time we get lucky and some anomalous feature dominates the winter pattern in a way that makes it favorable for snow here.  Sometimes its the NAO (1996/2010).  Sometimes its the EPO (2003, 2014).  It is becoming obvious this is NOT one of those years.  The rest of the time the pattern is flawed and we will scrape and claw to get any snow and if we are lucky a couple times the winter is at least decent with a couple snow events...or if we fail to get lucky they can end up total dumpster fire years like 2002.  Keep in mind even 2002 had a great period of NAO blocking and a few threats that just didnt work out, one got suppressed, one was slightly too warm in the boundary layer in the coastal plain, one just didnt come together and ended up the only small snow event of the year.  With some luck we get a couple of those to hit and we remember 2002 like a lot of other typical mediocre winters.  On the other hand 2000 had one good period over 10 days where 2-3 storms hit depending on where you were...but only one was really big in 95.  What if that one storm did get suppressed like the guidance thought?  We would remember that like we do 2002.  If this is not going to be 1996/2003/2010/2014...and its probably NOT, then we are going to have to deal with flawed patterns and hope we get lucky a couple times to eek out a mediocre year with some snow.  That is just how it is.  And that is how it is most of the time.  

[frd]

1 hour ago, psuhoffman said:

It is not a cold pattern look.  But...looking at some of those storms from the 50's, 60's, 70's, even 80's and 90s....I have to wonder if the atmospheric base state is cold enough right now for that to work. 

 

We don't need extreme cold for the favored period as you mention. Maybe arctic air waits for late Feb , seriously.  Wonder if we go to a typical Nino pattern in the later stages of the every two week pattern.  If we can flood Canada with super frigid air in mid Feb and then deliver it via an improving NAM state maybe it is possible. The ridge pushing West during Feb fits the Nino progression as you mentioned as well.  

We know during early Feb and on we will have the active STJ . Another time period to note is one that also seems to be on a pattern,  and I am referring to the PV vacillation cycle.....( in  strong Vortex winters ) ...date of the 20th of the month , as HM posted days ago, ( see last two HM posts  ) it has been going on near that date on a regular basis. Wonder if that ties into a significant event for us near Feb 18 th to the 22 nd.  

 

 

 

 

[Ralph Wiggum]

The silence from Bob Chill is telling/deafening.

[Bob Chill]

4 minutes ago, Ralph Wiggum said:

The silence from Bob Chill is telling/deafening.

 

2 minutes ago, Mersky said:

Or possibly he is busy with work??? 

Bingo. Getting crushed this week. I've passed the torch until further notice. As much as I like snow... I like making money better...

[psuhoffman]

@frd

BAMWX is focusing on energy, and that is almost entirely temperature dependent...and given the recent bias and the look of ridging across canada cutting off cross polar flow...I would lean normal to slightly above overall also.  But we are mostly hunting snow which is much different.  We don't need an arctic dump in mid winter to get a snowstorm.  

[jaydreb]

12z GFS looks good .... if you live in Maine.