December Medium/Long Range Discussion

[Chris78]

2 minutes ago, clskinsfan said:

I mean he is just pointing out that the setup is perfect for a big storm. Trying to nail down the day it happens from 10 days out is laughable. 

He was woofing for the 14 - 18th time period back at the end of November/ Beginning of December. He nailed that. 

Everyone in this subforum would of liked the final results to be further south but their was a major winter Storm in the East during the time frame he was woofing.

[osfan24]

11 minutes ago, clskinsfan said:

I mean he is just pointing out that the setup is perfect for a big storm. Trying to nail down the day it happens from 10 days out is laughable. 

That's fine, but he was woofing for the swing and a miss in early December, and saying it's the best look since 1996 is ridiculous. No credible met would say that.

[psuhoffman]

11 minutes ago, CAPE said:

I don't wanna hijack the thread, but I am saying that if there been a block leading in, and with better confluence/ more of a suppressive mechanism, the evolution would probably have been different enough that the surface low/850 low tracks would have been further SE, and the temp profile colder, thus a better outcome for places further south and east. Nothing to do with HECS, just in general, underscoring the importance of a -NAO/ 50-50 combo, making the timing less critical. Ofc there are other aspects(upstream) that had it played out a little differently, could have also led to a better outcome.

I think we might be differing based on perspective of location.  I was analyzing based on 95 but that’s different from the eastern shore in coastal synoptic events. We did have a -NAO and a 50:50. The NAO wasn’t perfectly centered but how often is it?  The high was still located near Montreal as the storm turned the corner in SC. To me that’s not a problem.  The surface track ended up fine. That crazy up the bay track didn’t verify. It tracked east of VA beach then NNE to just off cape may. Of course that’s inside of where you want it but honestly you need a completely different look then west of the bay.  You either need a progressive wave look or in the case of an amplified coastal setup a damn near PERFECT setup to score. With a coastal track a 3-6” to mix event in DC is mostly rain for you.  But 95 has had warning events with the track that verified before. A slightly colder airmass and they would have this time. Or a slightly better mid level phased system.  I can’t stress enough how anomalous that disconnect between the surface and mid levels was. It is NOT common to get 30-40” along the PA NY border from a surface system that tracks outside VA beach and Cape May. Their perfect track would be tucked up the Chesapeake Bay!  There is a reason those areas don’t typically get 20”+ snowstorms. They are usually too far inland to benefit much from coastals. Or had that exact setup been in Jan/Feb with cooler SST even with the disconnect I doubt we see as fast a warm surge. With that mid level track we were never getting a HECS but could have had a warning level mix event into 95. But like I said...for the eastern shore not so much.  It’s super difficult there. So much has to go exactly perfect that I get where you’re coming from. 

[SnowGoose69]

3 minutes ago, psuhoffman said:

I think we might be differing based on perspective of location.  I was analyzing based on 95 but that’s different from the eastern shore in coastal synoptic events. We did have a -NAO and a 50:50. The NAO wasn’t perfectly centered but how often is it?  The high was still located near Montreal as the storm turned the corner in SC. To me that’s not a problem.  The surface track ended up fine. That crazy up the bay track didn’t verify. It tracked east of VA beach then NNE to just off cape may. Of course that’s inside of where you want it but honestly you need a completely different look then west of the bay.  You either need a progressive wave look or in the case of an amplified coastal setup a damn near PERFECT setup to score. With a coastal track a 3-6” to mix event in DC is mostly rain for you.  But 95 has had warning events with the track that verified before. A slightly colder airmass and they would have this time. Or a slightly better mid level phased system.  I can’t stress enough how anomalous that disconnect between the surface and mid levels was. It is NOT common to get 30-40” along the PA NY border from a surface system that tracks outside VA beach and Cape May. Their perfect track would be tucked up the Chesapeake Bay!  There is a reason those areas don’t typically get 20”+ snowstorms. They are usually too far inland to benefit much from coastals. Or had that exact setup been in Jan/Feb with cooler SST even with the disconnect I doubt we see as fast a warm surge. With that mid level track we were never getting a HECS but could have had a warning level mix event into 95. But like I said...for the eastern shore not so much.  It’s super difficult there. So much has to go exactly perfect that I get where you’re coming from. 

As far as I know this was only the second storm on record where BGM and ALB recorded 20 plus inches and NYC also had 10 or more.  3/3/93 was the only other case

[psuhoffman]

1 minute ago, SnowGoose69 said:

As far as I know this was only the second storm on record where BGM and ALB recorded 20 plus inches and NYC also had 10 or more.  3/3/93 was the only other case

Not surprisingly Imo. That disconnect between the mid levels and the surface while limiting big totals on the southern area also created a HUGE expense of significant snow. The initial WAA fgen snowfall band set up for a time where you would expect with that surface track. But the mid levels ended up driving the forcing WAY further NW then typical. 

[CAPE]

13 minutes ago, psuhoffman said:

I think we might be differing based on perspective of location.  I was analyzing based on 95 but that’s different from the eastern shore in coastal synoptic events. We did have a -NAO and a 50:50. The NAO wasn’t perfectly centered but how often is it?  The high was still located near Montreal as the storm turned the corner in SC. To me that’s not a problem.  The surface track ended up fine. That crazy up the bay track didn’t verify. It tracked east of VA beach then NNE to just off cape may. Of course that’s inside of where you want it but honestly you need a completely different look then west of the bay.  You either need a progressive wave look or in the case of an amplified coastal setup a damn near PERFECT setup to score. With a coastal track a 3-6” to mix event in DC is mostly rain for you.  But 95 has had warning events with the track that verified before. A slightly colder airmass and they would have this time. Or a slightly better mid level phased system.  I can’t stress enough how anomalous that disconnect between the surface and mid levels was. It is NOT common to get 30-40” along the PA NY border from a surface system that tracks outside VA beach and Cape May. Their perfect track would be tucked up the Chesapeake Bay!  There is a reason those areas don’t typically get 20”+ snowstorms. They are usually too far inland to benefit much from coastals. Or had that exact setup been in Jan/Feb with cooler SST even with the disconnect I doubt we see as fast a warm surge. With that mid level track we were never getting a HECS but could have had a warning level mix event into 95. But like I said...for the eastern shore not so much.  It’s super difficult there. So much has to go exactly perfect that I get where you’re coming from. 

Yes there was a -NAO numerically. It wasn't a block though. Seeing red at h5 up over GL does not equal a block. 50-50 lows don't go racing into the NA unimpeded if there is a block. A block, as you said, will slow down/trap a 50/50 underneath. We did not have that for this past storm, and I was just using it as an example. I was AGREEING with the key point of your initial post. Remember? 

[SnowGoose69]

5 minutes ago, psuhoffman said:

Not surprisingly Imo. That disconnect between the mid levels and the surface while limiting big totals on the southern area also created a HUGE expense of significant snow. The initial WAA fgen snowfall band set up for a time where you would expect with that surface track. But the mid levels ended up driving the forcing WAY further NW then typical. 

I remember thinking the models were going to blow it because I didn’t understand the disconnect up in NJ given how far south the whole transfer and development happened.  In the end they did end up blowing how far north the surface low would get by NJ before it kicked east.  This caused the CCB feature to impact the NYC metro more than any guidance suggested 

[psuhoffman]

My bigger worry for the post Xmas threat is a miller b screw job not cutter. I’m talking about the Dec 28 period. Anything after that is way too far out to worry about. 

[PivotPoint]

4 hours ago, frd said:

 

For once I can say that is starting to look better.  Models are still catching on to the blocking scenario and eventual outcomes at the lower latitudes. 

Also, I have not seen this blocking signature for some time, evident by the temp anomalies to our far NE via the Canadian 10 day mean. 

 

 

 

 

This is a signal for cold dry alternating with warm and wet, imo. The anomalies in western Canada is a result of troughing below AK and that split flow that Ralph mentions below. So I see this as cold periods followed by an undulating PNA, which isn’t horrible but won’t allow amplification without a steady PNA that drives to dig south.

4 hours ago, Ralph Wiggum said:

The trof is in the Aleutian chain. Thats not a horrible look with a split flow off the West coast.

Yea, it looks like (to me) that the axis of the entry point of the northern branch is at too high a latitude for us to see the streams merge where we need them to. We need that ridge to be closer and further down in the west coast, and the ak trough to migrate so it stops squeezing that west coast ridge. That will pump up heights in the middle of the country which gives us that alternating cold dry, warm wet.

[psuhoffman]

3 minutes ago, CAPE said:

Yes there was a -NAO numerically. It wasn't a block though. Seeing red at h5 up over GL does not equal a block. 50-50 lows don't go racing into the NA unimpeded if there is a block. A block, as you said, will slow down/trap a 50/50 underneath. We did not have that for this past storm, and I was just using it as an example. I was AGREEING with the key point of your initial post. Remember? 

My bad 

[CAPE]

2 minutes ago, psuhoffman said:

My bad 

lol no worries.

[psuhoffman]

5 minutes ago, PivotPoint said:

This is a signal for cold dry alternating with warm and wet, imo. The anomalies in western Canada is a result of troughing below AK and that split flow that Ralph mentions below. So I see this as cold periods followed by an undulating PNA, which isn’t horrible but won’t allow amplification without a steady PNA that drives to dig south.

Yea, it looks like (to me) that the axis of the entry point of the northern branch is at too high a latitude for us to see the streams merge where we need them to. We need that ridge to be closer and further down in the west coast, and the ak trough to migrate so it stops squeezing that west coast ridge. That will pump up heights in the middle of the country which gives us that alternating cold dry, warm wet.

It’s not our most typical look but it’s worked before

[Maestrobjwa]

4 minutes ago, psuhoffman said:

My bigger worry for the post Xmas threat is a miller b screw job not cutter. I’m talking about the Dec 28 period. Anything after that is way too far out to worry about. 

Count on it...none of of our bigger snows have come between Dec 25th and New Years...something always seems to happen (i.e. Dec. 2010.) It's just a time where the atmospheric dice don't roll right, lol

[PivotPoint]

26 minutes ago, osfan24 said:

That's fine, but he was woofing for the swing and a miss in early December, and saying it's the best look since 1996 is ridiculous. No credible met would say that.

Yea, I never understood woofing and calling out HUGE dates like a 96 storm. Those storms are just so rare and anomalous, it’s like when you put that out there you’re encouraging people to amp a “possible” storm and promote ideas that almost NEVER happen. It’s a little sensational, imo.

I like the period coming up after xmas cutter. But there’s a lot of issues I see too, for example an unstable PNA regime, East based blocking. Doesn’t seem that we have a lot of cold air around either. Each year that goes by seems harder and harder to generate the surface temps we need for a good snow storm. 

[psuhoffman]

Wrt my h5 post from 2000 above one key to getting that to work is the extension of the east based NAO ridge west into the Hudson Bay region.  

[PivotPoint]

4 minutes ago, psuhoffman said:

It’s not our most typical look but it’s worked before

Doesn’t that kind of suggest a more horizontal flow and less amplification for us? That WAR too is the type of confluence we’d like either, correct?

[psuhoffman]

Just now, PivotPoint said:

Doesn’t that kind of suggest a more horizontal flow and less amplification for us? That WAR too is the type of confluence we’d like either, correct?

That’s the H5 from the end of January 2000. 

[psuhoffman]

Euro doesn’t dive enough energy far enough south to do much for out Xmas wave idea. Just some flurries after the front unless you’re in the extreme NW parts of the region. 

[Weather Will]

WB 12Z EURO now in line with GFS with arrival of cold on Christmas.

[Weather Will]

I have zero expectations for more snow before Christmas but the models have not figured it out yet....compare WB 0z EURO to 12Z Friday 1 am.

[Huffwx]

26 minutes ago, psuhoffman said:

That’s the H5 from the end of January 2000. 

We have high heights over Greenland but the block extends to near the Azores. 

[Maestrobjwa]

2 minutes ago, Weather Will said:

I have zero expectations for more snow before Christmas but the models have not figured it out yet....compare WB 0z EURO to 12Z Friday 1 am.

Yeah to me seems to be enough ambiguity to deem Christmas flakes as a toss-up right now...I wonder if this is one of those ones where details that are usually ironed out Day 3 or sooner could give us a chance!

[nj2va]

52 minutes ago, psuhoffman said:

My bigger worry for the post Xmas threat is a miller b screw job not cutter. I’m talking about the Dec 28 period. Anything after that is way too far out to worry about. 

I haven’t seen the surface maps but 12z Euro has a monster closed 500 low off ACY for 12/30. 

ETA:  Great Lakes low jumps off the coast of DE and strengthens as it heads to the cape.  Slams interior upstate NY.   Block exerting its influence on the GL low.

[Amped]

Can we buy a 50/50 low?

[snowman19]

4 minutes ago, Amped said:

Can we buy a 50/50 low?

You also need to buy a +PNA....there’s a full latitude trough on the west coast

[Maestrobjwa]

15 minutes ago, nj2va said:

I haven’t seen the surface maps but 12z Euro has a monster closed 500 low off ACY for 12/30. 

ETA:  Great Lakes low jumps off the coast of DE and strengthens as it heads to the cape.  Slams interior upstate NY.   Block exerting its influence on the GL low.

Alright I'm a bit confused here...GL lows are bad, right? And can't they impact a Miller B screwjob? My thoughts on this are a bit jumbled because all I can remember is the March 2018 Heartbreakers where that dang low dove down and screwed up the timing or something. @psuhoffman perhaps you can clarify what happened there?

[Maestrobjwa]

4 minutes ago, JakkelWx said:

Don't invest in anything dude...lol

[chris21]

1 hour ago, psuhoffman said:

It’s not our most typical look but it’s worked before

There are a lot of people jumping to conclusions re: H5 looks that I don’t think are necessarily correct. If you read the extensive research PSU has some on the subject, you will find that more often than not... the pattern does not need to be perfect to get snow. In fact, most of our decent snow events do not have all of the following (+pna, -EPO, -NAO, -AO). The H5 looks being thrown out the GFS and the Euro in the extended are very workable, and with a few minor adjustments could really lead to a special period. I’d highly recommend everyone read PSUs research on the subject.

[MJO812]

8 minutes ago, JakkelWx said:

Mean has a low along the coast  with blocking up top.

[JakkelWx]

4 minutes ago, MJO812 said:

Mean has a low along the coast  with blocking up top.

Yeah I saw the EPS mean. Banana high over top. I broke my own rule looking at the OP and not waiting for the ENS to come out