Winter 2017-18 Disco

[psuhoffman]

6 hours ago, Bob Chill said:

Hmmm.... Cohen's blog yesterday had a blurb that said pretty much the same thing that I posted a few days ago....lol

"I would conclude that the three factors that I consider favorable for severe winter weather increased atmospheric blocking in the fall, more extensive Siberian snow cover and low Arctic sea ice have become the norm more than the exception over the past decade.  I do believe that the lack of variability in these three factors, likely reduces their utility in winter predictions"

 

I do like this though:

"The latest plot of the tropospheric polar cap geopotential heights (PCHs) shows cold/below normal PCHs in the stratosphere but normal PCHs in the troposphere (Figure 10).   The forecast is for renewed warm PCHs in the troposphere, which would favor an increase in high latitude blocking to close out the month. This could also be signaling a pattern change to seasonable to seasonably cold temperatures across Northern Asia, Europe and/or the Eastern US at the end of October and the beginning of November. Also the longer the warm PCHs persists in the troposphere the more likely is troposphere-stratosphere coupling to become active, which favors a weak PV".

 

We've had nothing but a strong trop and strat PV to kick off met winter since basically 2010 but the last 3-4 years have been really bad. We're still a full month away from getting a bead on how the trop/strat is going to look to kick off met winter. Anything that happens in Nov that favors a weaker PV will be very welcomed. 

You made an excellent catch. I thought so when you pointed it. Made perfect logical sense. And confirmed by the source as a valid theory. Impressive find!  Good job...as usual. 

[BristowWx]

One thing I notice is the op GFS in la la land range has gone from fairly chilly to summer like heat in one run.  Taking 28 Oct, next Saturday, as the example.  Probably means nothing, being an op run,  but a hallmark of last year was fantasy blocking and cold that switched to searing heat in the uber long range which seemed to most often pan out.  Let's see where this ends up.  Now the GEFS tells a different tale for now so I remain with guarded optimism.  

[mitchnick]

39 minutes ago, BristowWx said:

One thing I notice is the op GFS in la la land range has gone from fairly chilly to summer like heat in one run.  Taking 28 Oct, next Saturday, as the example.  Probably means nothing, being an op run,  but a hallmark of last year was fantasy blocking and cold that switched to searing heat in the uber long range which seemed to most often pan out.  Let's see where this ends up.  Now the GEFS tells a different tale for now so I remain with guarded optimism.  

Last year taught me to always confirm the GEFS when they show a trough/cold with with the GEPS. These are links to the latest runs of the GEPS & GEFS @ 384 hrs.  Guess what? Don't buy the GEFS in the long range at this point.

https://www.tropicaltidbits.com/analysis/models/?model=gfs-ens&region=nhem&pkg=z500a&runtime=2017101718&fh=384&xpos=0&ypos=0

https://www.tropicaltidbits.com/analysis/models/?model=gem-ens&region=nhem&pkg=z500a&runtime=2017101712&fh=384&xpos=0&ypos=338

[BTRWx]

4 hours ago, SnowGoose69 said:

Cold Novembers are more a classic mod-strong Nino head fake tendency before things usually begin to torch December onward.  Ninas as you found are usually all over the place.  I thnik some of the stronger La Ninas have shown tendencies for cold Octobers in the East. 

I noticed that favorable and unfavorable winter weak ninas here both tend to produce cold November patterns over this region.  The next challenge is to find a warm weak nina November that was +snow for winter.  I may eta what I find.

eta: The only year I've found is 1964 (17")...Such limited analog anomalies are so fascinating to me!

[psuhoffman]

2 hours ago, BristowWx said:

One thing I notice is the op GFS in la la land range has gone from fairly chilly to summer like heat in one run.  Taking 28 Oct, next Saturday, as the example.  Probably means nothing, being an op run,  but a hallmark of last year was fantasy blocking and cold that switched to searing heat in the uber long range which seemed to most often pan out.  Let's see where this ends up.  Now the GEFS tells a different tale for now so I remain with guarded optimism.  

 

1 hour ago, mitchnick said:

Last year taught me to always confirm the GEFS when they show a trough/cold with with the GEPS. These are links to the latest runs of the GEPS & GEFS @ 384 hrs.  Guess what? Don't buy the GEFS in the long range at this point.

https://www.tropicaltidbits.com/analysis/models/?model=gfs-ens&region=nhem&pkg=z500a&runtime=2017101718&fh=384&xpos=0&ypos=0

https://www.tropicaltidbits.com/analysis/models/?model=gem-ens&region=nhem&pkg=z500a&runtime=2017101712&fh=384&xpos=0&ypos=338

When it snows we often times give the long range guidance too much credit because some of it hinted at snow. There is always some noise in the long range between all the available guidance. So some of it hinted at snow and it snowed.  But I'm sure there was some data saying no snow and that was equally wrong. 

The same happens when it doesn't snow. We say the guidance sucked way more then it did often times. Last year the uber long range only gave a strong signal for a colder pattern 4 times. Mid December. Early January. Late January into early February and in march. 

The rest of the winter we were stuck in torch mode and the guidance picked up on the coming torch periods each time. And all 4 colder patterns hinted at did come to fruition. But the warmth totally outdid the modest cold. In the end the warm periods were torches and the cold were just seasonal. Except march, that was legit cold.  But each of the 4 colder pattern did bring at least one opportunity for snow. None of them really worked out.  I'm December one cut west and was an ice storm then the trailing waves didn't develop.  In early January one missed southeast. I'm late January we had a perfect track and it was just slightly too warm them we had a good setup fall apart when a vort got shredded coming across the Conus then a wave system went just north. Then in march one system got suppressed then a close miss north. But we had 4 windows of legit opportunities and the guidance picked them out 2 weeks out. The details didn't lead to snow but that's not how you use 10-15 day guidance.  And the fact it didn't snow that much in your specific.locations didn't make the guidance awful.  At range the models picked up on each better pattern at day 15 and by 5-7 days out they also were seeing that the first 3 were transient and not going to last and showing signs of a return to warm day 15 again. In terms of general pattern recognition I thought they were decent enough.

they definitely had details wrong. But using day 10-15 guidance to get specifics is crazy. They also overestimated blocking time and again. That did often times cause a "great" look to end up only so so. But that's different from if the models were crying wolf on a pattern change that never came over and over. We had variability. But it was between blowtorch warm and average temps. 

The overall pattern last year sucked. But we also got unlucky. That's how you end up with a total dud. We easily could have lucked into at least one of those storms during the 4 decent periods but we didn't. The range last year was between really awful and just a typical crappy winter. We got unlucky with specific storm tracks so god awful it was. But I don't want to start misremembering how the long range guidance performed. Not getting snow sucked but that's not all I look at. Some I feel only look at snow on the ground when judging things. 

[40/70 Benchmark]

On October 15, 2017 at 9:46 PM, SimeonNC said:

This probably won't mean much but with the negative QBO, I think we do have a higher chance to see some blocking but things can always change and there are other indices that can affect the pattern. But I'm still optimistic about this winter compared to the last two.

Considering the state of the ssts in that region last summer, it probably means something.

I think we'll get some blocking.

[BTRWx]

13 minutes ago, 40/70 Benchmark said:

Considering the state of the ssts in that region last summer, it probably means something.

I think we'll get some blocking.

Imo, very few winters go without any blocking at some point between November and March.

 

[40/70 Benchmark]

20 minutes ago, BTRWx said:

Imo, very few winters go without any blocking at some point between November and March.

 

Well, "blocking" to me implies SUSTAINED, significant +height anomalies at higher latitudes....many winters, including the past few, have not had that.

[showmethesnow]

3 hours ago, psuhoffman said:

 

When it snows we often times give the long range guidance too much credit because some of it hinted at snow. There is always some noise in the long range between all the available guidance. So some of it hinted at snow and it snowed.  But I'm sure there was some data saying no snow and that was equally wrong. 

The same happens when it doesn't snow. We say the guidance sucked way more then it did often times. Last year the uber long range only gave a strong signal for a colder pattern 4 times. Mid December. Early January. Late January into early February and in march. 

The rest of the winter we were stuck in torch mode and the guidance picked up on the coming torch periods each time. And all 4 colder patterns hinted at did come to fruition. But the warmth totally outdid the modest cold. In the end the warm periods were torches and the cold were just seasonal. Except march, that was legit cold.  But each of the 4 colder pattern did bring at least one opportunity for snow. None of them really worked out.  I'm December one cut west and was an ice storm then the trailing waves didn't develop.  In early January one missed southeast. I'm late January we had a perfect track and it was just slightly too warm them we had a good setup fall apart when a vort got shredded coming across the Conus then a wave system went just north. Then in march one system got suppressed then a close miss north. But we had 4 windows of legit opportunities and the guidance picked them out 2 weeks out. The details didn't lead to snow but that's not how you use 10-15 day guidance.  And the fact it didn't snow that much in your specific.locations didn't make the guidance awful.  At range the models picked up on each better pattern at day 15 and by 5-7 days out they also were seeing that the first 3 were transient and not going to last and showing signs of a return to warm day 15 again. In terms of general pattern recognition I thought they were decent enough.

they definitely had details wrong. But using day 10-15 guidance to get specifics is crazy. They also overestimated blocking time and again. That did often times cause a "great" look to end up only so so. But that's different from if the models were crying wolf on a pattern change that never came over and over. We had variability. But it was between blowtorch warm and average temps. 

The overall pattern last year sucked. But we also got unlucky. That's how you end up with a total dud. We easily could have lucked into at least one of those storms during the 4 decent periods but we didn't. The range last year was between really awful and just a typical crappy winter. We got unlucky with specific storm tracks so god awful it was. But I don't want to start misremembering how the long range guidance performed. Not getting snow sucked but that's not all I look at. Some I feel only look at snow on the ground when judging things. 

Please tell me that you write all this stuff down as you go through the winter. Otherwise your great memory recall is depressing considering half the time I can't remember what i had for dinner the night before.

[psuhoffman]

4 hours ago, showmethesnow said:

Please tell me that you write all this stuff down as you go through the winter. Otherwise your great memory recall is depressing considering half the time I can't remember what i had for dinner the night before.

I got very lucky to have a good memory.  Makes me "look" smart sometimes when really all it is is that I remember stuff. 

[BristowWx]

24 minutes ago, psuhoffman said:

I got very lucky to have a good memory.  Makes me "look" smart sometimes when really all it is is that I remember stuff. 

You have both.  Obviously a good memory but also smart enough to pick nearly the best location in our forum for maximum snowfall potential.  This is not by accident, you are a wise man.  And yes, we were unlucky last winter in many ways.  It takes a lot of things to go right for us to get the kind of winter events we enjoy but only a couple of things to go wrong for us to get the shaft.  Margin of error for us is limited.  Its what makes us special.  We suffer for our snow.   

[yoda]

The S word was mentioned this morning in the LWX AFD:

Guidance still shows a cold front and wave of low pressure
moving toward the region early next week, but are a bit less in
sync than last night. The GFS is significantly slower than the
EC in bringing the upper low and its associated surface wave
northeastward into the region, causing Monday to be drier on the
GFS than on the EC, with a faster drying trend as we head into
the middle of the week on the EC than on the GFS. Overall, will
keep chance of showers, and heavy rain remains possible, given
strong wave and potential for training along the stalling front.
Both models also still show a very deep trough digging over the
eastern US behind the system for mid-late week next week. This
is something that would likely end the growing season across
much of the region, while also perhaps trying to get a few snow
flakes flying, especially in our higher terrain. Still, there`s
a long time to watch this.

[NorthArlington101]

Digital snow thread time?

[BTRWx]

2 minutes ago, NorthArlington101 said:

Digital snow thread time?

My response to that should be obvious without going into details about implications, for good reason.

[Bob Chill]

The aluetian ridge is doing some dirtywork in the npac. -PDO signature showing up. I sorta expect a -pdo during a nina but they're usually not a good sign for winter in the east in the MA. I expect some reversal of the SSTA structure through the end of the month if the aluetian trough/goa ridge sets up but I pretty much expect the aluetian ridge to return in Nov. 

 

Nina is still looking pretty weak in general. 

[mitchnick]

4 minutes ago, Bob Chill said:

The aluetian ridge is doing some dirtywork in the npac. -PDO signature showing up. I sorta expect a -pdo during a nina but they're usually not a good sign for winter in the east in the MA. I expect some reversal of the SSTA structure through the end of the month if the aluetian trough/goa ridge sets up but I pretty much expect the aluetian ridge to return in Nov. 

 

Nina is still looking pretty weak in general. 

Not to worry yet. Look at the average SSTA for October, 1995. We'd be having kittens and snowman19 would be running in circles faster than the polar vortex from last year.

[Eskimo Joe]

NWS main account put out a Tweet saying their winter forecast will be released tomorrow.  How much you want to bet they go climo for a Nina or just do a broad brush 'EC'.

[Bob Chill]

Mitch, 95-96 had a +pdo (and a pretty strong one on that chart). That was probably one of the reasons the pattern was good for the east. I'm not saying it's the only reason of course. If the npac looked like 95-96 right now I would be pretty happy. 

[showmethesnow]

Came across this this morning. Take it for what it is worth. First pic is the 500mb anomaly chart for Oct 1 through Oct 15 of this year. Second pic is for Oct 1 through Oct 15 of 1983. Key on where the blocking is located (The higher height anomalies). Extremely good agreement between the two.

 

 

Now I thought I would extend this for a full month from Sept 15 to Oct 15. First pic is this year and the second is 1983. There is still very good agreement with where the blocking is located.

 

 

Here is a comparison of the different indices for September. Pretty good match across the board.

2017   Enso -.5   PDO +.32  QBO -15.28 NAO -.45

1983   Enso -.46 PDO +.91  QBO -7.75   NAO -.95

 

Here is how 1983 played out for Nov and Dec @ 500mb.

 

And before you ask, here are the snow totals for 1983/84.

BWI Nov T  Dec T  Jan 8.4  Feb T  Mar 6.1  Apr T  Total 14.5

Other locations in the east.

Boston 43 total

New York 29.2 total

Philly 21.6 total

DC 8.6 total

Looks as if we were on the southern edge of the snow totals as places to our north fared much better.

Temps? Dec and Jan were below average where as February absolutely torched. And for those hoping for an early spring 1983 is not it. March was way below and April came in below not to mention we saw snow in both months.

Again, take the above for what it is worth but I did find the similarities between these two years striking at this point in time.

 

 

[mitchnick]

4 hours ago, Bob Chill said:

Mitch, 95-96 had a +pdo (and a pretty strong one on that chart). That was probably one of the reasons the pattern was good for the east. I'm not saying it's the only reason of course. If the npac looked like 95-96 right now I would be pretty happy. 

I know the pdo ended up great in 95/96, but it was extremely cold in the southern Gulf of Alaska in 10/95 which would have given me pause without the benefit of hindsight. But this year is still close enough to break our way, which is all we can ask for at this point. 

[mitchnick]

2 hours ago, showmethesnow said:

Came across this this morning. Take it for what it is worth. First pic is the 500mb anomaly chart for Oct 1 through Oct 15 of this year. Second pic is for Oct 1 through Oct 15 of 1983. Key on where the blocking is located (The higher height anomalies). Extremely good agreement between the two.

 

 

Now I thought I would extend this for a full month from Sept 15 to Oct 15. First pic is this year and the second is 1983. There is still very good agreement with where the blocking is located.

 

 

Here is a comparison of the different indices for September. Pretty good match across the board.

2017   Enso -.5   PDO +.32  QBO -15.28 NAO -.45

1983   Enso -.46 PDO +.91  QBO -7.75   NAO -.95

 

Here is how 1983 played out for Nov and Dec @ 500mb.

 

And before you ask, here are the snow totals for 1983/84.

BWI Nov T  Dec T  Jan 8.4  Feb T  Mar 6.1  Apr T  Total 14.5

Other locations in the east.

Boston 43 total

New York 29.2 total

Philly 21.6 total

DC 8.6 total

Looks as if we were on the southern edge of the snow totals as places to our north fared much better.

Temps? Dec and Jan were below average where as February absolutely torched. And for those hoping for an early spring 1983 is not it. March was way below and April came in below not to mention we saw snow in both months.

Again, take the above for what it is worth but I did find the similarities between these two years striking at this point in time.

 

 

Personally,  you can keep 83/84! Except for the March clipper surprise, it sucked at BWI. 

[Bob Chill]

Just now, mitchnick said:

Personally,  you can keep 83/84! Except for the March clipper surprise, it sucked at BWI. 

I don't remember 83/84 that well. Something in the back of my head is telling me it was one of those years where if a couple missed ops panned out it could have changed everything. 

[mitchnick]

1 hour ago, Bob Chill said:

I don't remember 83/84 that well. Something in the back of my head is telling me it was one of those years where if a couple missed ops panned out it could have changed everything. 

The only thing I can remember from that winter was a frigid Christmas and the March clipper surprise. The problem with the winters from pre-internet days, is first, they are 20+ years ago and second, without the internet there wasn't as much hype or social awareness save TWC. Before TWC, there was nothing on that score. So basically,  what I'm saying is,  I remember diddly from that winter other than Christmas and the clipper.  Lol

[GramaxRefugee]

1983 set the record low temp for Christmas at 0f.

I recall some sneaky cold hanging around that winter.

[40/70 Benchmark]

Yea, I like that analog....'83-'84.

[40/70 Benchmark]

9 hours ago, mitchnick said:

Not to worry yet. Look at the average SSTA for October, 1995. We'd be having kittens and snowman19 would be running in circles faster than the polar vortex from last year.

'95-'96 had a pretty classic tripole.

[gymengineer]

11 hours ago, Bob Chill said:

I don't remember 83/84 that well. Something in the back of my head is telling me it was one of those years where if a couple missed ops panned out it could have changed everything. 

It was one of the more extreme gradient seasons (like 92/93) with IAD going over 22" contrasting with DCA's pitiful seasonal total. You would have enjoyed January 10-22 that season. We had two moderate snowfalls followed by a severe cold wave.  The first one was a rain to snow event that actually worked out, and the second one was a somewhat surprise cold 6" deal in our backyards. In the severe cold wave (the second of the season after the Christmas cold blast), IAD set its all time low of -18F in an ideal radiation night that hasn't been challenged since.

March was well above average snowfall-wise, starting with the clipper bomb early in the month paralyzing traffic very similarly to 1/28/11. It was a 4-6" blitz in our area, followed by a rare mid-March freezing rain event. Then the month ended with a sub-970 mb low passing over the Delmarva causing plenty of coastal flooding but also a 4" snow in our area. 

 

[mitchnick]

5 hours ago, gymengineer said:

It was one of the more extreme gradient seasons (like 92/93) with IAD going over 22" contrasting with DCA's pitiful seasonal total. You would have enjoyed January 10-20 that season. We had two moderate snowfalls bookending a severe cold wave.  The first one was a rain to snow event that actually worked out, and the second one was a somewhat surprise cold 6" deal in our backyards. In the severe cold wave (the second of the season after the Christmas cold blast), IAD set its all time low of -18F in an ideal radiation night that hasn't been challenged since.

March was well above average snowfall-wise, starting with the clipper bomb early in the month paralyzing traffic very similarly to 1/28/11. It was a 4-6" blitz in our area, followed by a rare mid-March freezing rain event. Then the month ended with a sub-970 mb low passing over the Delmarva causing plenty of coastal flooding but also a 4" snow in our area. 

 

Your description of it sounds a whole lot better than the BN snowfall of 14.5" that fell at BWI,  6.1" of which was the March clipper (it's possible the clipper was closer to 4" and the later system was the other 2", but I don't think so.) The March clipper did have thunder with it, but I remember being unimpressed after the Megolopolis storm the year before having hours and hours of it....spoiled weenie!  Lol

[WxUSAF]

NOAA winter outlook is out. Ninatastic as one would expect. AN temps (although lowest color shading above equal chances) and EC on precip.

[mitchnick]

3 minutes ago, WxUSAF said:

NOAA winter outlook is out. Ninatastic as one would expect. AN temps (although lowest color shading above equal chances) and EC on precip.

It would seem like Siberia around here compared to last year if that panned out. lol