January Long Range Disco Thread

[PhineasC]

We will be shoveling feet of epic pattern soon. 

[CAPE]

Just now, PhineasC said:

We will be shoveling feet of epic pattern soon. 

If you are up north none of this stuff matters very much.

Here we scratch and claw and hope all the stars align.

[psuhoffman]

5 minutes ago, LP08 said:

Better all the way around.  Still tries to dump the trough out west near the end but it was a solid step towards the GEFS compared to 0z eight the EPO.  We live to fight another day.

I actually like the end and about to show why. 

[PhineasC]

6 minutes ago, CAPE said:

If you are up north none of this stuff matters very much.

Here we scratch and claw and hope all the stars align.

The winter has been pretty lame up there too. In a relative sense, of course. My 50” and current 5” OTG are firmly below average. Temps have been really pedestrian as well. It basically hasn’t been all that different from a good far western burbs winter so far. 

[CAPE]

8 minutes ago, psuhoffman said:

I actually like the end and about to show why. 

Other than a more pronounced EPO ridge, I like the look in the NA.. stronger -NAO and lower heights off of the Maritimes.

[Weather Will]

WB 12Z EPS keeps hope alive if you can wait 10 plus days.  It will be very interesting to see if a distinct threat comes inside 10 days by the end of this upcoming week.  One extra ray of hope is the numbering of heavy hits slightly south of us in the extended period.  We are not in the  Southern edge of all the heavy hits.

[JakkelWx]

Another bingo square crossed off!

[CAPE]

Just now, PhineasC said:

The winter has been pretty lame up there too. In a relative sense, of course. My 50” and current 5” OTG are firmly below average. Temps have been really pedestrian as well. It basically hasn’t been all that different from a good western burbs winter so far. 

Yeah my friend in Conway says its really sucked there, and even though he is in a different world compared to where you are, I can imagine its been frustrating in a relative sense for most of that region.

[Isotherm]

On 1/8/2021 at 2:48 PM, frd said:

 

@Isotherm  Tom does this mean anything , enough to sway you that the event, although not a 5 day reversal, still might be considered major.  Any thoughts would be appreciated. 

 

 

 

 

 

The second dip and z10 split w/ mean zonal wind reversal for several days+, if it verifies, would attain the definition I described for major. As far as the real-world impact: it would aid in prolonging the +GP action center near Greenland, countervailing any increased SE-ridging resistance via the almost inevitable retraction of the upstream ridge by the end of January. The conducive north atlantic paradigm would thus maintain favorability in the Northeast/Mid-Atlantic beyond an ephemeral/short term window and potentially extend possibilities through the end of January. As it stands, these stratospheric outcomes do not alter my overarching thinking that mid-late January will provide heightened potential for snowfall in the Eastern US. Details remain indeterminate given the highly stochastic nature of snowfall, but I do not see any reason to abandon the notion that January will eventually produce wintry weather, to varying degrees depending upon locations.

[psuhoffman]

I like the end of the EPS run. 

That NAO/50/50 configuration is ideal.  I couldn’t draw it up better.  Would make it really hard for anything to cut.  Yes the main trough is west but the SE ridge is suppressed and flat and enough cold should bleed east under the block in that look.   That trough will also help eject energy that can slide under the blocking  

Look at the temperature and pressure profile

Thats really good.  The gradient is to our south but it’s not suppressive and the polar boundary is just to our north.  Plenty of cold to tap.

The mean SLP is screaming this kind of result imo!  

[cbmclean]

8 minutes ago, CAPE said:

Yeah my friend in Conway says its really sucked there, and even though he is in a different world compared to where you are, I can imagine its been frustrating in a relative sense for most of that region.

Given the NA temp anomalies since November I'd be surprised if there is anywhere in the US where the snow is "good" compared to their climo.  Unless its some mountain area where they are getting more moisture than usual.

[psuhoffman]

21 minutes ago, PhineasC said:

We will be shoveling feet of epic pattern soon. 

Keep it up and we’ll be shoveling something...

[psuhoffman]

17 minutes ago, PhineasC said:

The winter has been pretty lame up there too. In a relative sense, of course. My 50” and current 5” OTG are firmly below average. Temps have been really pedestrian as well. It basically hasn’t been all that different from a good far western burbs winter so far. 

 

14 minutes ago, CAPE said:

Yeah my friend in Conway says its really sucked there, and even though he is in a different world compared to where you are, I can imagine its been frustrating in a relative sense for most of that region.

Not that uncommon for a high lat blocking pattern. What’s uncommon is there wasn’t the snowy response further south. There was the response in the storm track but it was just rainstorm after rainstorm. 

[CAPE]

For those who like to use snowfall means as a reference, 12z EPS is a big improvement over 0z, and almost identical to the 12z GEFS.

[psuhoffman]

1 minute ago, CAPE said:

For those who like to use snowfall means as a reference, 12z EPS is a big improvement over 0z, and almost identical to the 12z GEFS.

Shockingly this would make the 3rd time this cold season the EPS caved to the GEFS wrt long range longwave pattern.  The op GFS has been awful with synoptic details in the medium range lately but the GEFS since it’s major upgrade has been extremely good with pattern recognition. 

[PhineasC]

11 minutes ago, psuhoffman said:

 

Not that uncommon for a high lat blocking pattern. What’s uncommon is there wasn’t the snowy response further south. There was the response in the storm track but it was just rainstorm after rainstorm. 

It hasn’t even been cold up here though. Like 10-20 above average. I am fine with shunting the storm track south if I am cold as balls with upslope snow. But that’s not what happened. It’s like it’s still November. 

[nj2va]

21 minutes ago, psuhoffman said:

I like the end of the EPS run. 
 

That NAO/50/50 configuration is ideal.  I couldn’t draw it up better.  Would make it really hard for anything to cut.  Yes the main trough is west but the SE ridge is suppressed and flat and enough cold should bleed east under the block in that look.   That trough will also help eject energy that can slide under the blocking  

Look at the temperature and pressure profile

Thats really good.  The gradient is to our south but it’s not suppressive and the polar boundary is just to our north.  Plenty of cold to tap.

The mean SLP is screaming this kind of result imo!  

As a visual kinda guy, these posts where you mark up the maps is really helpful to look for things I don’t even know to look for sometimes.  Appreciate the time you put into stuff like this.

[PhineasC]

If my lows are averaging in the upper teens/low 20s way up in the north this time of year (normal is around 3 degrees), there isn’t much hope of it being cold enough to snow down there for you guys. We got the mega-blocking pattern but there is just no cold air. 

[aldie 22]

2 minutes ago, PhineasC said:

If my lows are averaging in the low 20s way up in the north this time of year (normal is around 3 degrees), there isn’t much hope of it being cold enough to snow down there for you guys. We got the mega-blocking pattern but there is just no cold air. 

Stunning revelation...thanks

[CAPE]

1 minute ago, PhineasC said:

If my lows are averaging in the low 20s way up in the north this time of year (normal is around 3 degrees), there isn’t much hope of it being cold enough to snow down there for you guys. We got the mega-blocking pattern but there is just no cold air. 

Pacific puke is real.

Low of 27 here this morning was the first sub 30 low in at least a week?

It has been generally chilly though, with highs in the upper 30s-mid 40s. Very modified Pacific like.

[PhineasC]

1 minute ago, leesburg 04 said:

Stunning revelation...thanks

LOL enough salt for Cinco de Mayo at the local taco joint and then some. 

[PhineasC]

Just now, CAPE said:

Pacific puke is real.

Low of 27 here this morning was the first sub 30 low in at least a week?

It has been generally chilly though, with highs in the upper 30s-mid 40s. Very modified Pacific like.

Yeah, it’s hasn’t been warm up there. Just little variation. Basically 20-30 and overcast for days on end. 

[cbmclean]

Just now, CAPE said:

Pacific puke is real.

Low of 27 here this morning was the first sub 30 low in at least a week?

It has been generally chilly though, with highs in the upper 30s-mid 40s. Very modified Pacific like.

Oddly enough it been seasonal or maybe slightly below down here in NC.  This has me mostly happy because 10 days ago it looked like a pure torch for us.

[CAPE]

16 minutes ago, cbmclean said:

Oddly enough it been seasonal or maybe slightly below down here in NC.  This has me mostly happy because 10 days ago it looked like a pure torch for us.

I might be off here, but the oddity with this blocking pattern is the split Pac jet- where it has been cutting to our south but also straight across Canada, and keeping Polar air well north. We generally don't need major cold for snow when we have a -AO/NAO, but temps are not typically way above normal up in NNE. All the Polar air has been bottled up wayyy up north because of  the Pac air infiltration. Difficult to get relatively cold, dry air in place ahead of a storm with that setup, which is sort of the bread and butter of a HL block.

[SnowDreamer]

promising signs out of 12Z ensembles for the 18-20 threat window. GEFS control has a solid storm on the 19th and EPS shows some support (centered on the 20th). 

[Rvarookie]

Shout out to @CAPE and @psuhoffman for carrying the torch this year. At least it’s been better to read posts this year 

[psuhoffman]

43 minutes ago, PhineasC said:

It hasn’t even been cold up here though. Like 10-20 above average. I am fine with shunting the storm track south if I am cold as balls with upslope snow. But that’s not what happened. It’s like it’s still November. 

Blocking patterns aren’t always cold. Often they are quite mild north of the storm track. This year has been to the extreme though. 

[CAPE]

7 minutes ago, psuhoffman said:

Blocking patterns aren’t always cold. Often they are quite mild north of the storm track. This year has been to the extreme though. 

Agree, but read my most recent post. This seems a bit different than what we typically see. Maybe I am wrong though.

[CAPE]

24 minutes ago, Rvarookie said:

Shout out to @CAPE and @psuhoffman for carrying the torch this year. At least it’s been better to read posts this year 

Thanks, but what makes this fun is everyone contributing and sharing info and getting different perspectives. It's a group effort.

[psuhoffman]

10 minutes ago, CAPE said:

Agree, but read my most recent post. This seems a bit different that what we typically see. Maybe I am wrong though.

It just depends. Not all blocking patterns are the same. But a -NAO split flow isn’t uncommon and usually a good thing. It’s not a cold pattern.  Feb 2010 was one. The Polar jet was directed across Canada by the trough in the pac but the southern stream was splitting into the SW and coming across the gulf coast.  But the pac jet wasn’t as intense and the profile in Canada wasn’t as awful to start. But it wasn’t cold. Actually north of us was very mild. And even here it would have been 45 that week had there not been snow.  It’s a pick your poison thing. A split flow cuts off the polar air but normally in winter we can develop a just cold enough airmass under the flow to get snow with a good track. This year that didn’t work out. A -EPO -NAO non split flow is much colder but it can be a dryer pattern if storms dive in too far north to amplify under us and the STJ is cut off in that case. So there are pros and cons to both. FWIW the split flow option accounts for a lot of our HECS storms.