October/November 2019 Mid/Long Range

[psuhoffman]

45 minutes ago, WxUSAF said:

The cold shots that we’ve had and are about to have seem to have some strat influence, which is limiting the influence of the MJO as it’s moved through warm phases. Last winter, MJO dominated over the strat influence for most of the winter. MJO will get into the colder phases as we move into the 2nd half of the month and it also seems that the strat will continue to get beat up (see Mike Ventrice’s Twitter). So I think there still should be cold air around for much of the month. But what happens in December? Does the MJO heading back into warm phases have an influence? Does the decadal warm December trend happen? Or does the strat continue to help favor some cold air getting down into the eastern CONUS?

It's not a bad sign though imo, that even with some factors not right (like the MJO) we are still getting anomalous cold intrusions into the CONUS.  In really crap years one of the telling signs that the base state is just not good is how difficult it can be to get cold.  

[psuhoffman]

19 minutes ago, Bob Chill said:

One thing we prob all suspect and agree on is a stout relaxation of the current very anomalous Nov cold is coming. I'm sure either late Nov or early Dec ends up being pretty warm for a time. Which is totally normal and happens like every single year and stuff. lol

Dec 2013 was interesting. Cold early, down right hot, and then the hammer. I don't mind December having a sig warm period but I do mind it when it's all the eye can see for 2, 3, or even 4 weeks. I really have no idea what's in store for Dec but I know what to look for. If Dec goes end up cold or at least has a decent duration period of real winter wx in the east then some of the seasonal forecasts aren't going to look so good. 

Frankly I don't mind a 7-10 day warm period in ANY part of winter...so long as its not endless warmth with no end in sight as you say.  Even some of the best winters had a warm period somewhere.  People just don't remember the torch week that happened in between all the snow.  It's extremely rare, like once every 20 years or so, that we get a winter without at least one anomalously warm period somewhere.  Might as well get it out of the way early...

[Bob Chill]

1 minute ago, psuhoffman said:

Frankly I don't mind a 7-10 day warm period in ANY part of winter...so long as its not endless warmth with no end in sight as you say.  Even some of the best winters had a warm period somewhere.  People just don't remember the torch week that happened in between all the snow.  It's extremely rare, like once every 20 years or so, that we get a winter without at least one anomalously warm period somewhere.  Might as well get it out of the way early...

agreed. Especially early on as wavelengths are still transitioning. We can get some nasty warmth/ridging in Dec. It gets much harder in Jan/Feb but Dec has no problem turning on the heater. Dec 2013 hit 80 right? I remember it being insanely warm for a time. Had the windows open and it was too hot in the house. 

[BristowWx]

26 minutes ago, LP08 said:

12z GFS has snow early Tuesday from the NS.  Front pushed through much quicker.

Hopefully that vort gets under us.  Big ask I know.  

[frd]

25 minutes ago, psuhoffman said:

Granted he includes some factors and influences that are above my pay grade into his calculus BUT he is going with a pacific pattern that is opposite of what it is trending towards right now. 

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.

   

[osfan24]

35 minutes ago, LP08 said:

12z GFS has snow early Tuesday from the NS.  Front pushed through much quicker.

Basically no accumulation at all though.

[Maestrobjwa]

7 minutes ago, frd said:

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.

   

Now wait a minute...I thought the solar minimums tended to do the opposite? (neg NAO) Albeit sometimes it would be a lag and not show up until the next winter)

[frd]

2 minutes ago, Maestrobjwa said:

Now wait a minute...I thought the solar minimums tended to do the opposite? (neg NAO) Albeit sometimes it would be a lag and not show up until the next winter)

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. "

[frd]

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

 

 

[Bob Chill]

18 minutes ago, Maestrobjwa said:

Now wait a minute...I thought the solar minimums tended to do the opposite? (neg NAO) Albeit sometimes it would be a lag and not show up until the next winter)

Don't worry about the NAO at long leads. The domain space is very small and slight variations in the upper level pattern greatly affect the calculated NAO. The predictive skill of the NAO beyond just 1-2 weeks is terrible. The AO is different as it covers MUCH more real estate. Solar mins generally mean better chances of a -AO. Sometimes that goes hand in hand with the NAO and other times they are completely disconnected. 

If you pick 1 index to focus on definitely stick with the AO and nothing else. It has the highest correlation (by far) as to how much or little snow the mid atlantic receives on average. Right now the AO looks favorable through most of Nov. If that carries into Dec then we can start drawing some conclusions as a Dec -AO of -1.2 or lower has like an 80% predictive skill of above normal snow. 

The NAO acts more like a traffic cop and is much more unpredictable and volatile. Our biggest storms happen with a -NAO relaxing towards neutral or positive (Archambault event). That's for bigger storms though. The AO controls our snow chances in general. The only thing that can easily override a -AO is a tragic Pacific. 2012 is a great example of the way we can fail even with a favorable AO. If you want to focus on the NAO then you want it to be very volatile with periods of deep negative followed by relaxations repeatedly. A stout -NAO park in place kinda sucks here. The SE loves it but not us. The AO is different in that we just want a stable -AO for as long as possible. 

[Bob Chill]

1 hour ago, leesburg 04 said:

Imho we will know in about 3-4 months for sure

That's if we survive that long. We may be down to half staff before the end of Dec. Iso's forecast already took out the weak.  I'm all in until I'm out

[psuhoffman]

59 minutes ago, frd said:

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.

   

He said that during the solar decline before the minimum the NAO trends more positive, and if we look at the last few cycles the winters leading up to the minimum did feature mostly +AO/NAO winters.  

[psuhoffman]

1 hour ago, BristowWx said:

Hopefully that vort gets under us.  Big ask I know.  

Not thrilled with the current look on guidance but enough time to change.   It's evolving towards the lead northern stream vort being the main player, and that also is trending more out ahead of the main trough meaning the boundary would likely be north of us initially and then we are stuck with the old cold chasing precip and we all know how that works out.  It had more potential when there were multiple waves riding the boundary and we could get one of them to clip us after the cold push.  If the only game ends up that initial vort we are in trouble imo.  But a LONG way to go with such a delicate setup.  But right now its going the wrong way imo.  

[caviman2201]

12Z Euro says nope.

 

[mappy]

that's still a dusting IMBY, that i will happily take in mid-november. 

[WxUSAF]

Ggem and euro both flipped back to a more amplified primary low that cuts inland. Round and round we go. 

[H2O]

Alabama gets more snow than we do.  We clearly live too far north and east and warm and dry

[Bob Chill]

13 minutes ago, WxUSAF said:

Ggem and euro both flipped back to a more amplified primary low that cuts inland. Round and round we go. 

Pretty much what I've been expecting unfortunately. It's exceptionally hard to defy Nov climo. 

[NorthArlington101]

12z GEFS was a fairly significant improvement on the 06z for those trying to find hope. 

while I'm on it, the CMC ens (looking at the individual members is loltastic) also were a significant jump

[BristowWx]

1 minute ago, NorthArlington101 said:

12z GEFS was a fairly significant improvement on the 06z for those trying to find hope. 

while I'm on it, the CMC ens also were a significant jump

No reason to abandon ship just yet..we have more time to take on water.  Euro had snow in KY so just hoping for first flakes now.  Flawed weenie logic. 

[Maestrobjwa]

2 minutes ago, Bob Chill said:

Pretty much what I've been expecting unfortunately. It's exceptionally hard to defy Nov climo. 

Which makes the 1.7 inches we managed last November a monumental event...lol I mean, one look at the snow records over the last 140 years tells ya how hard it is to defy the climo! (By my count, only 15 Novembers on record had snowfall that topped an inch...The highest being 8.5 inches in Nov. of 1938)

[WinterWxLuvr]

35 minutes ago, WxUSAF said:

Ggem and euro both flipped back to a more amplified primary low that cuts inland. Round and round we go. 

The gfs ensemble looked that way yesterday evening imo. Looks pretty much like a cold front at this point. But who knows. And like many have said, it’s very early. Last year was pretty unusual.

[Bob Chill]

4 minutes ago, Maestrobjwa said:

Which makes the 1.7 inches we managed last November a monumental event...lol I mean, one look at the snow records over the last 140 years tells ya how hard it is to defy the climo! (By my count, only 15 Novembers on record had snowfall that topped an inch...The highest being 8.5 inches in Nov. of 1938)

True but I was mostly thinking about the type of setup more than Nov being hostile in general. We'd struggle with this identical setup in Jan/Feb so Nov makes it that much harder. I will say the cold front itself is pretty exceptional for Nov. Record lows might get broken. Getting a wave with a narrow 100mi stripe of precip to line up right is asking a lot. When I first saw this pop up on guidance my first thought was the precip will most likely roll through as rain before the front.

We can't write it off yet as fast moving shortwaves like this typically aren't modeled with accuracy until 72 hours or so. It could pop back up at any time but once we get to 72 hours or less it needs to be either really close or overhead on guidance. 

[WxUSAF]

17 minutes ago, Bob Chill said:

Pretty much what I've been expecting unfortunately. It's exceptionally hard to defy Nov climo. 

 

1 minute ago, WinterWxLuvr said:

The gfs ensemble looked that way yesterday evening imo. Looks pretty much like a cold front at this point. But who knows. And like many have said, it’s very early. Last year was pretty unusual.

I’m rooting for first flakes. Accumulation is major bonus. I’d wager we aren’t done with snow chances for November on next Wednesday. But it is still November.

[Cobalt]

5 minutes ago, WinterWxLuvr said:

The gfs ensemble looked that way yesterday evening imo. Looks pretty much like a cold front at this point. But who knows. And like many have said, it’s very early. Last year was pretty unusual.

We got pretty lucky with that because it was a consistent slug of moisture that was heading our way. We didn't really have to worry about precipitation or rates, just ptype. Even with a pretty unseasonable airmass like that, November climo took over. I hope these potential storms that trend into just light to no precip aren't a general theme this year

[midatlanticweather]

From what i saw, the Euro Ens were better for area wide snow - maybe less for some, but more for quite a few. Clearly - there is no clarity.. except we know this is unlikely to be anything big...  Not saying accumulating snow, but a better feel for snow! Maybe some dust.. maybe the best areas see some white mulch.. or a cartopper

 

 

[yoda]

EPS looked a lil better for snow prospects than the OP IMO

[mappy]

Just now, midatlanticweather said:

From what i saw, the Euro Ens were better for area wide snow - maybe less for some, but more for quite a few. Clearly - there is no clarity.. except we know this is unlikely to be anything big... 

 

so we just wait and see? 

[midatlanticweather]

1 minute ago, mappy said:

so we just wait and see? 

Ya! I guess that is always the case! LOL! In Your Back yard it may be more.. you know.. because.. 

 

[NorthArlington101]

EPS looked a lil better for snow prospects than the OP IMO

something something, lock it up.

Comparing between 0z, Jackpotville lost some snow, as well as a second maximum in SE VA, but overall a little more for most if not just equivalent. Definitely not a run that suggests the threat is over.