Part II, Thanksgiving week transient cold shot and the pattern beyond

[weathafella]

I think this will be a transient pattern change with the PNA spike EPO dip but no real sign of the AO or NAO flipping.

Why does that make it transient? We certainly have had stupendous winter periods with a positive NAO.

[ORH_wxman]

so snow on thursday?

The inverted trough on the weekend looks half decent. That will at least be a pretty sharp cold air mass even if it doesn't snow.

I like the pattern developing near the 10th of december on the Euro ensembles. It has some potential. The lower height anomalies from the +NAO are starting to press southeast from Davis straight into NE Canada like they did in Dec 2007.

[Ginx snewx]

I think this will be a transient pattern change with the PNA spike EPO dip but no real sign of the AO or NAO flipping.

93/94 transient lasted 2.5 months, why do you think its transient and what do you make of the ENS AO progged and current extreme drop

[40/70 Benchmark]

Why does that make it transient? We certainly have had stupendous winter periods with a positive NAO.

Yea, the lack of NAO\AO in and of themselves do not make it transient...we have built entire winters that way.

[OKpowdah]

I think good blocking waits until mid Jan...until then, its gradient city.

Still have good confidence that we see a SSW in the first few days of January that sends us all running to make fires in the public library

[40/70 Benchmark]

The inverted trough on the weekend looks half decent. That will at least be a pretty sharp cold air mass even if it doesn't snow.

I like the pattern developing near the 10th of december on the Euro ensembles. It has some potential. The lower height anomalies from the +NAO are starting to press southeast from Davis straight into NE Canada like they did in Dec 2007.

Exactly.

Steve, just bustn', bro.

[Ginx snewx]

Yea, nothing wrong with that pattern...not optimal, but not a dead ratter, either.

Steve, I guess we just semntics each other to death...not far off in actuality.

Very much the same thoughts, no matter what you will get your 80+, beat Kevin. Man the global snowcover is nuts and that will help the pattern down the road.

[OKpowdah]

The inverted trough on the weekend looks half decent. That will at least be a pretty sharp cold air mass even if it doesn't snow.

I like the pattern developing near the 10th of december on the Euro ensembles. It has some potential. The lower height anomalies from the +NAO are starting to press southeast from Davis straight into NE Canada like they did in Dec 2007.

That's what I'd really like to see

[Ginx snewx]

Exactly.

Steve, just bustn', bro.

Yep and me too, some stuffed shirts around so I gotta be careful who to bust with.

Ya know I still am thinking and have been thinking about that Dec 03 storm in a crappy pattern. That GFS run last night for day ten sure brought back that memory. Will be interesting to see if the 8-10th time frame pops a coastal, full moon zone.

[weathafella]

Yep and me too, some stuffed shirts around so I gotta be careful who to bust with.

Ya know I still am thinking and have been thinking about that Dec 03 storm in a crappy pattern. That GFS run last night for day ten sure brought back that memory. Will be interesting to see if the 8-10th time frame pops a coastal, full moon zone.

Ginny gale ftw?

[skierinvermont]

Why does that make it transient? We certainly have had stupendous winter periods with a positive NAO.

Yea, the lack of NAO\AO in and of themselves do not make it transient...we have built entire winters that way.

I don't mean that we won't see snow.. in mid-winter most of NE can see snow from any pattern that is not a complete torch. I just mean I don't see sustained blocking coming up and the +PNA is probably transient as is common in Ninas.

EDIT: Wes just posted in the main forum a couple minutes ago about how he thinks it will likely be transient as well.

[Ginx snewx]

Still have good confidence that we see a SSW in the first few days of January that sends us all running to make fires in the public library

tearing up library of congress books, ripping up furniture, boys crying for their Mommas?

[CoastalWx]

I don't mean that we won't see snow.. in mid-winter most of NE can see snow from any pattern that is not a complete torch. I just mean I don't see sustained blocking coming up and the +PNA is probably transient as is common in Ninas.

Wes just posted in the main forum a couple minutes ago about how he thinks it will likely be transient as well.

As long as we can get ridging in the Aleutians to be amplified enough to help dump the cold se...we don't have to depend on the -NAO like the MA does. That's what we need to be on the lookout for. We don't want the ridging to weaken as it pulls west, otherwise the se ridge will flex once again.

[Ginx snewx]

Ginny gale ftw?

I was really hoping it snowed on your birthday, when was the last time you had a bonafide birthday snowstorm?, damn OT, but what the heck.

[weathafella]

I don't mean that we won't see snow.. in mid-winter most of NE can see snow from any pattern that is not a complete torch. I just mean I don't see sustained blocking coming up and the +PNA is probably transient as is common in Ninas.

EDIT: Wes just posted in the main forum a couple minutes ago about how he thinks it will likely be transient as well.

1993-94 had a hostile NAO and was one of the coldest and snowiest if my life. I think most patterns in early and mid December are transient.

[weathafella]

I was really hoping it snowed on your birthday, when was the last time you had a bonafide birthday snowstorm?, damn OT, but what the heck.

Never happened. Perhaps the closest was December of 1957 with about a foot a few days later.

[skierinvermont]

1993-94 had a hostile NAO and was one of the coldest and snowiest if my life. I think most patterns in early and mid December are transient.

yes but 93-94 you had a huge -AO and -EPO to work with. I think the -AO is pretty unlikely any time soon.

Not saying it can't happen but I see a reversion to +EPO -PNA +AO +NAO as probable. Even then can still snow CNE and NNE though.

[toronto blizzard]

What do the ooz Euro ensembles show by the end of the period (after 240 hours to 360 hours)?

[Organizing Low]

The only thing we need to watch out for is the PNA and EPO at the end of the run. The PNA may fall again, especially as the ridge retrogrades towards the Aleutians. If that is the case, then we will need that ridge to be amplified, otherwise the se ridge will flex.

that negative PNA is a real piece of ****

that PNA going negative is pretty much what ended last winter (for you guys, never began here)... if i recall properly?

[CoastalWx]

The GEFS are going berserk with the MJO wave in phase 4. Just mouse over NCPE and NCPB and you'll see what mean. The other models aren't nearly as strong as the GFS and ensembles. Might lower confidence in GEFS, but the MJO isn't always accurately de[icted anyways.

http://www.cpc.ncep....clivar_wh.shtml

In either case, the models seem to want to go to phase 5 and 6 and sort of rot there. At least the Euro ensembles do.

Phase 5 and 6 have some similarities to the upcoming pattern, but we are just entering December, so these posted composites below may not be totally correct, but it gives the idea. Phase 6 would be nice.

P5

P6

[ORH_wxman]

Phase 6 looks like the Euro ensembles in the long range...a few details aside, pretty close.

[toronto blizzard]

The GEFS are going berserk with the MJO wave in phase 4. Just mouse over NCPE and NCPB and you'll see what mean. The other models aren't nearly as strong as the GFS and ensembles. Might lower confidence in GEFS, but the MJO isn't always accurately de[icted anyways.

http://www.cpc.ncep....clivar_wh.shtml

In either case, the models seem to want to go to phase 5 and 6 and sort of rot there. At least the Euro ensembles do.

Phase 5 and 6 have some similarities to the upcoming pattern, but we are just entering December, so these posted composites below may not be totally correct, but it gives the idea. Phase 6 would be nice.

P5

P6

Would this be for DEC 10th or so timeframe or early december?

[weathafella]

yes but 93-94 you had a huge -AO and -EPO to work with. I think the -AO is pretty unlikely any time soon.

Not saying it can't happen but I see a reversion to +EPO -PNA +AO +NAO as probable. Even then can still snow CNE and NNE though.

Why is it probable?

[CoastalWx]

Would this be for DEC 10th or so timeframe or early december?

Yeah like Will said...Phase 6 on the composite isn't unlike what the euro ensembles show. There is still time for it to trend for the better or worse, so lets hope it holds going forward. We haven't really taken any steps back over the last few days, so hopes of this continuing are decent I suppose.

[weathafella]

yes but 93-94 you had a huge -AO and -EPO to work with. I think the -AO is pretty unlikely any time soon.

Not saying it can't happen but I see a reversion to +EPO -PNA +AO +NAO as probable. Even then can still snow CNE and NNE though.

AO was far from huge in 1993-94.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/monthly.ao.index.b50.current.ascii.table

[ORH_wxman]

AO was far from huge in 1993-94.

http://www.cpc.ncep....ent.ascii.table

All else equal, we'd like a -AO/NAO, but we have had many good periods in the past without it. Dec/Jan '75-'76 is one. '56-'57 and '07-'08 are two more. Lets not forget the blockbuster winter of '92-'93 which had an absolutely putrid AO/NAO configuration.

At any rate, the type of pattern that the Euro ensembles show in the LR is one we can cash in on. Doesn't mean it will happen, but its not a bad pattern for us. We'll hope it continues to show it as we get closer and hopefully a few threats materialize.

[weathafella]

All else equal, we'd like a -AO/NAO, but we have had many good periods in the past without it. Dec/Jan '75-'76 is one. '56-'57 and '07-'08 are two more. Lets not forget the blockbuster winter of '92-'93 which had an absolutely putrid AO/NAO configuration.

At any rate, the type of pattern that the Euro ensembles show in the LR is one we can cash in on. Doesn't mean it will happen, but its not a bad pattern for us. We'll hope it continues to show it as we get closer and hopefully a few threats materialize.

Oh I agree.....would rather neg AO/NAO but you can't use it's current state to support a transient EPO IMHO.

[Logan11]

Well the depressing reality is we have to wait a solid week to possibly get a normal or below normal day...... Jerry's 12/10 is getting closer and closer.

All else equal, we'd like a -AO/NAO, but we have had many good periods in the past without it. Dec/Jan '75-'76 is one. '56-'57 and '07-'08 are two more. Lets not forget the blockbuster winter of '92-'93 which had an absolutely putrid AO/NAO configuration.

At any rate, the type of pattern that the Euro ensembles show in the LR is one we can cash in on. Doesn't mean it will happen, but its not a bad pattern for us. We'll hope it continues to show it as we get closer and hopefully a few threats materialize.

[Clinch Leatherwood]

Well the depressing reality is we have to wait a solid week to possibly get a normal or below normal day...... Jerry's 12/10 is getting closer and closer.

Yep and the goalposts slowly are moving.

New GFS at least through 165ish has calmed down from the uber outbreak to a more seasonal cooling period up to that point. Chances center around 12/3 and 12/6, and then....

[weathafella]

Yep and the goalposts slowly are moving.

New GFS at least through 165ish has calmed down from the uber outbreak to a more seasonal cooling period up to that point. Chances center around 12/3 and 12/6, and then....

Who has moved the goalposts? The modeling has been pretty stable and the pattern change shouldn't begin for real until 12/10. It's pretty rare to get decent snow prior to 12/15 if you go back through the past 50 years clime records.