November Medium/Long Range Discussion

[psuhoffman]

15 hours ago, WxUSAF said:

^yeah, GEFS and EPS both have a strong +PNA/-EPO developing around Thanksgiving with our -NAO fading away. My instinct is that the PNA+EPO ridging is more useful for our early season snow chances since it’s a more effective cold air delivery mechanism and we need more anomalous BN temps in early December to snow. 

The monthly snowfall composites back that up 

[psuhoffman]

4 hours ago, Ji said:

No but I’m sure you did

I predicted slightly above normal snowfall this year 

[Eskimo Joe]

30 minutes ago, psuhoffman said:

I predicted slightly above normal snowfall this year 

[Eskimo Joe]

 

 

[WEATHER53]

1 hour ago, Eskimo Joe said:

 

 

The fatal word of “delay”

[TSSN+]

Exhilarating 

 

[Steve25]

I don’t hate this. Not as cold as some are advertising out there, but seems to like an active storm track

[Eskimo Joe]

4 hours ago, WEATHER53 said:

The fatal word of “delay”

Grit is famous for building in a 5 to 7 days delay on any pattern change. This is a wise choice.

[Chris78]

1 hour ago, Steve25 said:

I don’t hate this. Not as cold as some are advertising out there, but seems to like an active storm track

A December 5th snowfall would be great...

[Eskimo Joe]

11 minutes ago, Chris78 said:

A December 5th snowfall would be great...

Give us this: snow all along Appalachia: https://www.raymondcmartinjr.com/weather/2010/05-Dec-09.html

[Eskimo Joe]

 

 

[Eskimo Joe]

CFS for December is lit! Advocating above normal precip and below normal temps. That can only mean ONE THING! We torch for the first two days of the month and rain like heck, then flip to cold and dry while the weenies cry. /s

 

 

[frd]

 

I don't give a crap about the Canadian warming later in the month, say what you want, I just like the pretty colors. 

 

 

[Stormchaserchuck1]

Long range models around the turn of the month are wanting to develop some kind of 500mb low north of Hawaii, +PNA under the -EPO/-WPO. There really no sign of a RNA pattern. That's why I think the 3-4 week CPC outlook put out today, Euro weeklies, and seasonal monthlies for Dec (CFS, CanSips) are wrong having the cold in the Upper Midwest, and a SE ridge, above average in the SE, US, and average in the Mid Atlantic. MJO could be holding strength going into 7-8-1 around the 1st half of December, and I think it's a below average temperature pattern everywhere east of the Rockies, at least for the 1st half of the month. 

[Stormchaserchuck1]

18z GEFS  hr384

[Stormchaserchuck1]

14 minutes ago, frd said:

I don't give a crap about the Canadian warming later in the month, say what you want, I just like the pretty colors. 

If the peak is Nov 25-30, history says strong -NAO correlation, based around Dec 30 - Jan 4.  

[frd]

3 minutes ago, Stormchaserchuck1 said:

If the peak is Nov 25-30, history says strong -NAO correlation, based around Dec 30 - Jan 4.  

What are your thoughts on the SST profile in the NW Atlantic, North Central Atlantic outside of the MJO, QBO and strat in regards to the appearence of the warm, cold, warm tripole shown in this image below ? ( - NAO )  Is it significant, or will it change in a week or two and be meaningless ?  

 

[Stormchaserchuck1]

10 minutes ago, frd said:

What are your thoughts on the SST profile in the NW Atlantic, North Central Atlantic outside of the MJO, QBO and strat in regards to the appearence of the warm, cold, warm tripole shown in this image below ? ( - NAO )  Is it significant, or will it change in a week or two and be meaningless ?  

I've found that N. Atlantic SSTAs for Wintertime NAO pattern have a real strong correlation the leading May - August. I think later in the Fall and the Winter is more a product of the pattern, but there are pretty high correlation numbers at this time of the year as well. I think the Summer when things stabilize, subsurface temps can be seen in the surface SSTA profile. There is data that allows us to plot a list of 75-analog years to something like following Winter NAO conditions. In May-Aug the correlation goes up to +0.5 (75%)! but in Nov-Dec it's +0.25 (62.5%). Still a pretty strong correlation:

You really want to see cold water off the East coast from NC to off of New Foundland. Which I guess we have to some extent. The above map is default positive, so a negative NAO goes to the opposite of those anomalies. 

The tripole pattern pattern actually holds a future NAO state pretty well. 

The same tripole pattern works for Jan-Feb to March-Apr NAO, and really throughout the year. Pretty high leading pattern here, given how secondary SSTs are. 

[CAPE]

51 minutes ago, Eskimo Joe said:

CFS for December is lit! Advocating above normal precip and below normal temps. That can only mean ONE THING! We torch for the first two days of the month and rain like heck, then flip to cold and dry while the weenies cry.

 

 

Click bait. WB CFS is useless. That's a single run. That model is volatile af and changes like the wind. Only somewhat useful when averaged over several runs. If you look at it on Tropical Tidbits it is the average of the last 12 runs.

[Eskimo Joe]

16 minutes ago, CAPE said:

Click bait. WB CFS is useless. That's a single run. That model is volatile af and changes like the wind. Only somewhat useful when averaged over several runs. If you look at it on Tropical Tidbits it is the average of the last 12 runs.

...it was a joke  

[CAPE]

3 minutes ago, Eskimo Joe said:

...it was a joke  

Always hard to tell with you lol.

The point stands.

[Eskimo Joe]

16 minutes ago, CAPE said:

Always hard to tell with you lol.

The point stands.

Fair point. It's an online setting. I added the /s.

[poolz1]

Nice to see the GEFS today at the end of its ens run show the pattern the weeklies have been showing.  Always the risk of a can kick.  My biggest concern has been that the trough gets stuck in the west and delays the cold coming east.  Seems that risk is slowly decreasing.  The 5-10th once cold is established it may be game on.

 

[Stormchaserchuck1]

16 minutes ago, poolz1 said:

Nice to see the GEFS today at the end of its ens run show the pattern the weeklies have been showing.  Always the risk of a can kick.  My biggest concern has been that the trough gets stuck in the west and delays the cold coming east.  Seems that risk is slowly decreasing.  The 5-10th once cold is established it may be game on.

Love that deep trough NW of Hawaii. You don't can kick when the players are in position - it would take a whole re-alignment of the N. Pacific 500mb pattern, which is a little bit beyond the average model error. 

I think the wild card is the MJO and what it does. Seems models are betting on it staying strong. 

They want to have more of a -PNA pattern if the MJO goes weak, but I'm not seeing it: 21 of the last 29 months have been +PNA [CPC], and since the 23-24 Strong Nino flipped to negative-ENSO, 12 out of 19 months have been +PNA. 

[CAPE]

10 hours ago, poolz1 said:

Nice to see the GEFS today at the end of its ens run show the pattern the weeklies have been showing.  Always the risk of a can kick.  My biggest concern has been that the trough gets stuck in the west and delays the cold coming east.  Seems that risk is slowly decreasing.  The 5-10th once cold is established it may be game on.

 

 

10 hours ago, Stormchaserchuck1 said:

Love that deep trough NW of Hawaii. You don't can kick when the players are in position - it would take a whole re-alignment of the N. Pacific 500mb pattern, which is a little bit beyond the average model error. 

I think the wild card is the MJO and what it does. Seems models are betting on it staying strong. 

They want to have more of a -PNA pattern if the MJO goes weak, but I'm not seeing it: 21 of the last 29 months have been +PNA [CPC], and since the 23-24 Strong Nino flipped to negative-ENSO, 12 out of 19 months have been +PNA. 

There could easily be some error at this range in the exact positioning/orientation of the long wave features. I wouldn't call it a can kick but given the currently advertised position of the Pac trough and the downstream ridge over AK towards D15, its not hard to imagine a western US trough for a time at the beginning of Dec.

[Weather Will]

Latest EPS and GEFS extended MJO both head into Phase 7 by the end of the month after a long stall in warm Phase 6.  Question:  DT states 7 is still a warm phase in December while JB says 7 is ok in December.  Anyone have data on this topic.  If 7 is still warm we will wait until mid December for Phase 8.

[87storms]

From the latest ENSO PPT (backloaded winter vibes?)...

La Niña conditions are present.* Equatorial sea surface temperatures (SSTs) are below average across the central and east-central Pacific Ocean. Atmospheric anomalies over the tropical Pacific Ocean are consistent with La Niña. La Niña conditions are present and favored to persist through December 2025 - February 2026, with a transition to ENSO-neutral likely in January-March 2026 (55% chance).*

[leo2000]

13 minutes ago, Weather Will said:

Latest EPS and GEFS extended MJO both head into Phase 7 by the end of the month after a long stall in warm Phase 6.  Question:  DT states 7 is still a warm phase in December while JB says 7 is ok in December.  Anyone have data on this topic.  If 7 is still warm we will wait until mid December for Phase 8.

Yes, nothing awful about MJO phase 6 in December so of course phase 7 would be even better. 

 

 

Phase 6, La Nina DEC

[bncho]

3 minutes ago, leo2000 said:

Yes, nothing awful about MJO phase 6 in December so of course phase 7 would be even better. 

 

 

Phase 6, La Nina DEC

that's a LOT better than i'd expect

[TSSN+]

39 minutes ago, Weather Will said:

Latest EPS and GEFS extended MJO both head into Phase 7 by the end of the month after a long stall in warm Phase 6.  Question:  DT states 7 is still a warm phase in December while JB says 7 is ok in December.  Anyone have data on this topic.  If 7 is still warm we will wait until mid December for Phase 8.