December 2021 Medium/Long Range Discussion Thread

[Weather Will]

WB 0Z EPS…45 please 

[Weather Will]

Early morning update from Sterling NWS…

Beyond Sunday, forecast becomes far too uncertain to get too
far into details. However, there does appear to be a chance for
a coastal low pressure system nearby early next week with some
cold air potentially lingering in portions of the area. This
pattern would generally lend itself to wintry precip potential
primarily being over the higher elevations, but will have to
evaluate further as the threat comes closer into focus. For now,
have some mention of rain/snow on Monday. Exact timing is also
subject to change of course as guidance picks up on this
potential system. For now this system just needs to be monitored
for future updates.

[Weather Will]

WB 6Z GFS low still to track…

[midatlanticweather]

Looks like we are starting to see the trend again. System less amped, further south. Colder, yes... But this reminds me of the last potential. Slowly cutting back on totals. Hard to get wet systems in La Nina 

[North Balti Zen]

1 minute ago, midatlanticweather said:

Looks like we are starting to see the trend again. System less amped, further south. Colder, yes... But this reminds me of the last potential. Slowly cutting back on totals. Hard to get wet systems in La Nina 

Wut. It’s 7 days out. There is no trend. Yesterday afternoon there was nothing. 24 hours ago there was a hint of something. It’s a week out. These are all phantoms. 

[WinterWxLuvr]

24 minutes ago, midatlanticweather said:

Looks like we are starting to see the trend again. System less amped, further south. Colder, yes... But this reminds me of the last potential. Slowly cutting back on totals. Hard to get wet systems in La Nina 

Ji type analysis here

[CAPE]

A couple things looking at the latest ensemble runs. The High that settles in after the weekend 'event' brings temps back to around normal for Monday. It also is on the move east as the system of interest approaches. As of now it looks like a decent chance for a coastal low to develop, but exactly where and how close to the coast is uncertain. The degree of interaction with the NS low is a big unknown- GEFS has a more prominent low and the EURO much weaker. Still lots to sort out with the primary features. As for chances of frozen just looking at the big picture at this juncture, not surprising that it favors inland at elevation, but at 6+ days out, this is obviously subject to some significant changes.

 

 

[mappy]

31 minutes ago, WinterWxLuvr said:

Ji type analysis here

i lold. 

[H2O]

Next week storm is 100% Polar Express type thing.  If you can't hear the bell it won't snow.

[Solution Man]

14 minutes ago, H2O said:

Next week storm is 100% Polar Express type thing.  If you can't hear the bell it won't snow.

We all know where this is headed

[Tar Heel Snow]

I’m going to be in NC for Christmas, so I’m certain it will actually snow up here next week lol

[Tar Heel Snow]

https://twitter.com/webberweather/status/1470566092523270145?s=12

[WinterWxLuvr]

When do you guys think they’ll issue warnings?

[Solution Man]

16 minutes ago, WinterWxLuvr said:

When do you guys think they’ll issue warnings?

Brine Watches definitely 

[Scarlet Pimpernel]

23 minutes ago, WinterWxLuvr said:

When do you guys think they’ll issue warnings?

Don't we usually get the "Watch List" first, and then the "Reaper Call"??

[StormchaserChuck!]

The last 3 times the PNA was <-1.00 in December, the rest of the Winter was -NAO, -PNA, I've seen that these types of things play out in real time vs later. Before then you have to go to the 1990s to have a -PNA December. 

[BTRWx's Thanks Giving]

It's kind of strange how the MJO is being modeled to race toward the null circle and then back out.

[psuhoffman]

2 minutes ago, BTRWx&#x27;s Thanks Giving said:

It's kind of strange how the MJO is being modeled to race toward the null circle and then back out.

It's not actually a linear thing like those charts imply.  There are conflicting areas of convection that are both calculated into mapping those charts...as the one near the MC dies out the wave in the Pacific takes over as the dominant factor in mapping those charts and so you suddenly see the wave move towards phase 8.  

[frd]

Cool animation.  Like Webb states, far from perfect,  but shows one possible progression moving forward. 

 

 

[frd]

 

This is unusual.  It did happen in Jan 1980.

 

 

[midatlanticweather]

3 hours ago, WinterWxLuvr said:

Ji type analysis here

LOL! How about that 12z run? Is there a trend now?

https://www.pivotalweather.com/model.php?rh=2021121412&fh=165&dpdt=loop&mc=&pwplus=1

 

[psuhoffman]

I don't waste a lot of time digging deep into synoptic details of storms past day 5 but one thing I have noticed is that the runs that have a better storm eject the northern stream system further south out west.  The runs that eject that feature further north end up without much of a storm at all.  It seems the STJ isn't capable of getting it done alone, and this would be typical so believable in a nina.  We're probably going to need the NS to phase in and at a far enough south latitude for this to work.  

As for a "trend" that feature seems to be bouncing all over run to run on the guidance.  But the preponderance of evidence is north/no good.  But there is a large enough minority clustering of guidance with a further south NS feature not to completely write it off yet.  But its more complicated than just "north or south" trend since there are two features here and we actually need a south trend with one of them in order to get a north trend with the other.  

[87storms]

1 minute ago, psuhoffman said:

I don't waste a lot of time digging deep into synoptic details of storms past day 5 but one thing I have noticed is that the runs that have a better storm eject the northern stream system further south out west.  The runs that eject that feature further north end up without much of a storm at all.  It seems the STJ isn't capable of getting it done alone, and this would be typical so believable in a nina.  We're probably going to need the NS to phase in and at a far enough south latitude for this to work.  

As for a "trend" that feature seems to be bouncing all over run to run on the guidance.  But the preponderance of evidence is north/no good.  But there is a large enough minority clustering of guidance with a further south NS feature not to completely write it off yet.  But its more complicated than just "north or south" trend since there are two features here and we actually need a south trend with one of them in order to get a north trend with the other.  

yea, both systems are running in tandem, but too much separation.  need a diggier northern stream instead of a continuation of what we've seen for the last month or two.  at least we've gotten a few days of sunshine.  i'll take that over what we had for the last month even if it takes us out of the clipper game...because that wasn't working anyway.

[Wonderdog]

31 minutes ago, midatlanticweather said:

LOL! How about that 12z run? Is there a trend now?

https://www.pivotalweather.com/model.php?rh=2021121412&fh=165&dpdt=loop&mc=&pwplus=1

 

I was just going to give you kudos but you beat me to it.

[North Balti Zen]

Quote

Is there a trend now?

no

 

You are big mad because a 7 or 8 day phantom may or may not be there and emotionally want to handle your disappointment by being excited to be the first to say "SEE I TOLD YOU IT WAS A PHANTOM"

Be better than this.  Post better. Read more. Etc. 

[Heisy]

41 minutes ago, psuhoffman said:

I don't waste a lot of time digging deep into synoptic details of storms past day 5 but one thing I have noticed is that the runs that have a better storm eject the northern stream system further south out west.  The runs that eject that feature further north end up without much of a storm at all.  It seems the STJ isn't capable of getting it done alone, and this would be typical so believable in a nina.  We're probably going to need the NS to phase in and at a far enough south latitude for this to work.  

As for a "trend" that feature seems to be bouncing all over run to run on the guidance.  But the preponderance of evidence is north/no good.  But there is a large enough minority clustering of guidance with a further south NS feature not to completely write it off yet.  But its more complicated than just "north or south" trend since there are two features here and we actually need a south trend with one of them in order to get a north trend with the other.  

Exactly, unfortunately 12z runs thus far just skimming the northern S/W across the lakes, no digging or chasing, won't cut it. 

[jaydreb]

At least we still get Torchmas?

[Ji]

The storm on the 18th went a ton more north than other runs....first bad sign

[BristowWx]

6 minutes ago, jaydreb said:

At least we still get Torchmas?

I knew this would be posted.  Op runs are wrong this far out....unless of course

[CAPE]

Some of y'all might have a better idea about the 'trends' if you stopped looking at op run surface maps.