November Weather Discussion

[CoastalWx]

NAM too

 

I don't think it's really a squall type situation perhaps. Seems like some frontogenesis and lift...not exactly a strong line along the front and then stratiform precip behind it, if you know what I mean. Maybe that's why those types of models don't see it? Or they could be right...lol.

[CoastalWx]

Yeah I think even a flip results in a slow cool down. Definitely looks mild but I think there's light at the end of the tunnel.

 

Yeah that's about how I view it too.

[weatherwiz]

It would be great to get some cold air to build up north and sustain itself so we eventually have something to tap into besides crap airmass

[Typhoon Tip]

I'm getting fairly confident of a positive AO winter...most signs point to that right now. However, that doesn't mean we still cannot have fun. 2007-2008, 1992-1993, 1983-1984, 1975-1976, and 1956-1957...and believe it or not 2004-2005 and 2008-2009 were slight +AO winters as defined by DJF...but 2005 had a big -AO in March if you include that month.

 

Keep the big ugly vortex away from the EPO region, and we can still have our fun...esp with latitude.

 

What are those ?

 

I don't think so -- but then again, I'm particularly horrible at seasonal outlooks.   My skills are in intra-season affairs ... picking out tele modalities, and their potential implications on igniting specific events.   Not sure why that doesn't translate into season outlooks but...whatever. 

 

Anyway, I respectively disagree.  The multi-decadal, linear tracking of the AO has reversed phase over the last 10 years... This is cyclic across 20 to 30 years.  The last nadir was in the 1970s, and there was an apex in the 1990s, and now 15 to 20 years later we are descending again. 

 

Though we are in a solar max, it has been dim compared to typical maxes.  (Although just this last week things sparked up a bit with X class flares).  Still, stratospheric ozone population is above normal.  This image appears to have glitched upon the last update ...

 

 

still, we get enough impression here that the positive anomalies out-weight the current negative regions, suggesting a surplus ozone load.  As we know ... ozone presence tends to correlate with SSW events -- though this statement does not bear any QBO correlation.   SSW's don't characterize whole seasons, no.  

 

The QBO does side with your thinking though.   So you got that -- perhaps the root of your thinking.   The correlation is modest in December, but strengthens somewhat into January, before interestingly, ...becoming rather incoherent in February.  The problem there is, February and March can often bring the goods to New England as we all well know.  

 

But, as Cohen and other works have shown, +AO Octobers tends to flip phase going into DJF.  There's lots of theorized reason there, but that's the gist.  On a kind of spatial level, it's hard to have the index stay biased longer than 40 to 60 days, just based purely on Rossby re-ordering influencing domain spaces.  

 

I don't know ... I guess if the QBO is the end-all/be-all driver than according to the CDC's correlation matrix, the QBO has a 1.0 positive coefficient relationship with the AO in Dec, maturing to 2.0 in Jan, before going to -0.03 in Feb.  Otherwise, the ancillary environmental factors that I am looking at might suggest more negative AO.  

[CoastalWx]

John I also agree with Will. The QBO, SAI, new OPI, current stratospheric state etc all argue for it. But (and this is a big but) you can stil get away with some sort of dateline or even PNA ridging with a +AO. It also does not mean the AO or NAO won't have a stage where it goes negative...hell it could do that for a month of we have a SSW or wave breaking event. I'm no expert myself, it's just my guess. I've seen some thoughts that the early acceleration in snow cover over Siberia could bring a December -NAO and then we switch, HM touting a possible -NAO for a time in December, and also a back end winter with a possible SSW.  Sounds like the consensus for now isn't high confidence, but it seems like we may have an overall +AO.

[Typhoon Tip]

John I also agree with Will. The QBO, SAI, new OPI, current stratospheric state etc all argue for it. But (and this is a big but) you can stil get away with some sort of dateline or even PNA ridging with a +AO. It also does not mean the AO or NAO won't have a stage where it goes negative...hell it could do that for a month of we have a SSW or wave breaking event. I'm no expert myself, it's just my guess. I've seen some thoughts that the early acceleration in snow cover over Siberia could bring a December -NAO and then we switch, HM touting a possible -NAO for a time in December, and also a back end winter with a possible SSW.  Sounds like the consensus for now isn't high confidence, but it seems like we may have an overall +AO.

 

 

I am admittedly less learned about the correlation (or why...) of the "SAI" and "OPI".  I'll have to check that out!  

 

But I don't agree the the current stratospheric state argues for that.  I just pointed out the ozone presence, which is conducive to warming events/suppression.  The wick so to speak, is primed.

 

Also, I'll go ahead and point out the fragility of the QBO's correlation:

The QBO's positive phase is normally weaker than the negative phase, and that intuitively, if not a-priori exemplifies it has more disconnect during the positive phase..  In other words, I would be more expecting a -AO during -QBO, then necessarily a +AO during a +QBO.  If there is going to be a statistical break-down, it is "somewhat" more likely during the positive phase(s).

 

Case in point, in August of 2010, the QBO switched from negative to positive, and remained that way through April of 2011.  During that time, through January, the AO was negative the majority of time.   In fact, that winter had that 45-day, 60" thing if you might recall.  

 

But again, the SAI and OPI may very well signal some environmental factors.  

[CoastalWx]

John I also agree with Will. The QBO, SAI, new OPI, current stratospheric state etc all argue for it. But (and this is a big but) you can stil get away with some sort of dateline or even PNA ridging with a +AO. It also does not mean the AO or NAO won't have a stage where it goes negative...hell it could do that for a month of we have a SSW or wave breaking event. I'm no expert myself, it's just my guess. I've seen some thoughts that the early acceleration in snow cover over Siberia could bring a December -NAO and then we switch, HM touting a possible -NAO for a time in December, and also a back end winter with a possible SSW.  Sounds like the consensus for now isn't high confidence, but it seems like we may have an overall +AO.

 

I will also add that it doesn't mean it will avg out to +3SD or something. It could be something like 0.5 when averaged out DJFM. Obviously the latter would be a lot better for us.

[CoastalWx]

I am admittedly less learned about the correlation (or why...) of the "SAI" and "OPI".  I'll have to check that out!  

 

But I don't agree the the current stratospheric state argues for that.  I just pointed out the ozone presence, which is conducive to warming events/suppression.  The wick so to speak, is primed.

 

Also, I'll go ahead and point out the fragility of the QBO's correlation:

The QBO's positive phase is normally weaker than the negative phase, and that intuitively, if not a-priori exemplifies it has more disconnect during the positive phase..  In other words, I would be more expecting a -AO during -QBO, then necessarily a +AO during a +QBO.  If there is going to be a statistical break-down, it is "somewhat" more likely during the positive phase(s).

 

Case in point, in August of 2010, the QBO switched from negative to positive, and remained that way through April of 2011.  During that time, through January, the AO was negative the majority of time.   In fact, that winter had that 45-day, 60" thing if you might recall.  

 

But again, the SAI and OPI may very well signal some environmental factors.  

 

Yeah I see the ozone argument and that could help down the road. What I meant was that the eastern Siberia region at 50mb is progged to be ice cold, and per "skierinvermont's" work done looking at November temps at 50mb in this area and the following winters..it also argued for a +AO. It very well may not work out....just saying what it showed.

 

Also, the QBO is slowly in the process of changing and I also saw some work showing the process of the QBO flipping aids in a -AO/-NAO so that does add to your argument. It will also depend on how quick this flip occurs and obviously we don't know yet.

 

I'll say it again...we still could have a prolonged period of a -NAO or perhaps it's just a weakly +AO...both would be welcomed. We are in the -NAO cycle so naturally you think -NAO as a background state, but you can have some + years thrown in during a predominant -NAO regime.

[HoarfrostHubb]

Actually some tstms south of Maine right now.

Blizz mentioned a chance of them

[CoastalWx]

Blizz mentioned a chance of them

 

What can I say, he's the most interesting man in the world.

[Snowstorms]

Yeah I see the ozone argument and that could help down the road. What I meant was that the eastern Siberia region at 50mb is progged to be ice cold, and per "skierinvermont's" work done looking at November temps at 50mb in this area and the following winters..it also argued for a +AO. It very well may not work out....just saying what it showed.

 

Also, the QBO is slowly in the process of changing and I also saw some work showing the process of the QBO flipping aids in a -AO/-NAO so that does add to your argument. It will also depend on how quick this flip occurs and obviously we don't know yet.

 

I'll say it again...we still could have a prolonged period of a -NAO or perhaps it's just a weakly +AO...both would be welcomed. We are in the -NAO cycle so naturally you think -NAO as a background state, but you can have some + years thrown in during a predominant -NAO regime.

 

 

There's a chance we could a see a SSW development later in the Winter season around late January-early February in my opinion. This may allow a prolonged period of cold anomalies and perhaps snowy conditions to persist longer than normal, again like you said, it depends how the QBO behaves and so forth.  

 

I still like my original idea of a Mid-late December through much of January warm period across the East in general. The AO is extraordinarily high right now and its been a while since we have seen such an anomaly, could it be a sign of what's to come in the winter?  I like a 07-08 and 08-09 mix for this Winter. Those analogs are key in respect to whats been happening this year thus far. 

 

What do the Euro ensembles show in 10-15 day period? thanks! 

[OKpowdah]

Makes some sense that polar ozone would be at a surplus since we've been in this very prolonged Nina regime -> suppressed Pac convection and less water vapor punching into the stratosphere to destroy ozone. So the BDC has had full loads to drop off at the poles.

[jamesnichols1989]

I think it's fascinating trying to figure out the nature of the winter's teleconnection regime pattern.  It's a lot of educated guess work, but I'm interested in the nature of the Eastern Pacific Oscillation index and the pattern that it involves, because it has a downstream effect on the ridging in the PNA region.  PNA ridges have an effect on the kind of snowstorm that hits New England.

[weathafella]

Regardless of duration or even forecast veracity, AO on ensemble products is tanking in the extended.

[CoastalWx]

Makes some sense that polar ozone would be at a surplus since we've been in this very prolonged Nina regime -> suppressed Pac convection and less water vapor punching into the stratosphere to destroy ozone. So the BDC has had full loads to drop off at the poles.

 

Nice, never realized that. Thanks for dropping in.

[moneypitmike]

Really meh winds today.

 

44.5/32 with a gust recorded at 15mph. 

[jamesnichols1989]

I'm interested in the next trough that moves through the Northern US, that starts off near the West Coast of the US and then moves eastward through the Northern Plains, Great Lakes and then eventually the Northeast come near Thanksgiving.  There are some temps over the central US at around 850mb that reach -20C.  Now that is frigid air.  Of course that is if the models are right in the medium to long range.

[CoastalWx]

There's a chance we could a see a SSW development later in the Winter season around late January-early February in my opinion. This may allow a prolonged period of cold anomalies and perhaps snowy conditions to persist longer than normal, again like you said, it depends how the QBO behaves and so forth.  

 

I still like my original idea of a Mid-late December through much of January warm period across the East in general. The AO is extraordinarily high right now and its been a while since we have seen such an anomaly, could it be a sign of what's to come in the winter?  I like a 07-08 and 08-09 mix for this Winter. Those analogs are key in respect to whats been happening this year thus far. 

 

What do the Euro ensembles show in 10-15 day period? thanks! 

 

The euro ensembles show an interesting late 11-15 day. It's got a short wavelength pattern in the Pacific...that is ridge moving into the Bering Sea, trough in AK and then another ridge just off the west coast of the US. Full latitude trough develops from Hudson bay to the Gulf of Mexico with the pipeline of cold ready to move into the Plains. We look to be on the edge here in new England, but looks more volatile during that time. We may see the cold move in if we were to extrapolate beyond hr 360.

[jamesnichols1989]

NAM in agreement with the GFS on the evolution of the vorticity maximum associated with the arctic front.  Still some time before this Wednesday, but time is running out on potential storm, even though it's mainly out to sea right now.  I think models are still changing on overall evolution of the trough over the eastern US.

[jamesnichols1989]

I see the week of Thanksgiving as a volatile pattern setting up as we sit in the edge of the trough, storms could move over our region in that time period.  However models are in disagreement this far out which is to be anticipated.  Some warmth comes in after Thursday of this upcoming week.

[CoastalWx]

NAM is really dry until the last minute where it pics up moisture along the south coast.

[Baroclinic Zone]

Today has that look on models of maybe some low topped convection in places..One of those deals where maybe a bolt or two of lightning and some small hail and gusty winds under a few cells..particluarly in Ri and E Ma

Blizz mentioned a chance of them

Convection yes. Any hail or gusty winds? And off by a couple hundred miles.

[Snowstorms]

The euro ensembles show an interesting late 11-15 day. It's got a short wavelength pattern in the Pacific...that is ridge moving into the Bering Sea, trough in AK and then another ridge just off the west coast of the US. Full latitude trough develops from Hudson bay to the Gulf of Mexico with the pipeline of cold ready to move into the Plains. We look to be on the edge here in new England, but looks more volatile during that time. We may see the cold move in if we were to extrapolate beyond hr 360.

 

Sounds like an interesting pattern but the only problem is that its in the 11-15 day period. Up until then starting around Wednesday/Thursday we should get some SAB (slightly above normal temperature anomalies) to above normal.

 

By the looks of it, im assuming it shows the PV sliding south across Canada towards Hudson Bay, right? This might subside the effects of the SE ridge further south, building a tight gradient. For now, we want the West to stay cold and build a strong snow cover depth as the cold across the north isnt as important as the anomalies further south. The colder arctic this year amongst previous years may help retain stronger cold shots when they punch south.

 

Seems like a battle going on in the Pacific as the EPO begins turning negative and the PNA tries to revert to a more positive state, interesting. I still like my original idea of a cool down in and around the last week of November through early December. 

[CoastalWx]

Sounds like an interesting pattern but the only problem is that its in the 11-15 day period. Up until then starting around Wednesday/Thursday we should get some SAB (slightly above normal temperature anomalies) to above normal.

 

By the looks of it, im assuming it shows the PV sliding south across Canada towards Hudson Bay, right? This might subside the effects of the SE ridge further south, building a tight gradient. For now, we want the West to stay cold and build a strong snow cover depth as the cold across the north isnt as important as the anomalies further south. The colder arctic this year amongst previous years may help retain stronger cold shots when they punch south.

 

Seems like a battle going on in the Pacific as the EPO begins turning negative and the PNA tries to revert to a more positive state, interesting. I still like my original idea of a cool down in and around the last week of November through early December. 

 

Well the PV itself is still way up by the arctic, but a piece of cold air slides south.

[Snowstorms]

Well the PV itself is still way up by the arctic, but a piece of cold air slides south.

 

Yeah my apologizes should have worded it better...sounds interesting.

 

http://weather.gc.ca/forecast/city_e.html?nu-27&unit=i

 

At least much of the cold anomalies are on this side of the globe thus far this year. May bode well for strong cold shots whenever they occur in the Winter season. 

[Typhoon Tip]

I am less familiar with "Skierinvermont" 's analysis, but fwiw -- the current observation from the GFS initialization has modest, 50 hPa positive T anomalies in and around the Siberian regions...

 

 

And forecast that to remain at least modestly so out to D10 ...

 

 

As others have rightfully indicated... a -EPO/+AO is not a disaster, either.     

[CoastalWx]

I am less familiar with "Skierinvermont" 's analysis, but fwiw -- the current observation from the GFS initialization has modest, 50 hPa positive T anomalies in and around the Siberian regions...

 

 

And forecast that to remain at least modestly so out to D10 ...

 

 

As others have rightfully indicated... a -EPO/+AO is not a disaster, either.     

 

I was talking about the forecasts, but those forecasts for strat temps aren't all that accurate either.  Also noting these temps cooling once we lost the typhoon recurves.

 

[Clinch Leatherwood]

Lightning out of this complex moving over cape cod right now

[CoastalWx]

Lightning out of this complex moving over cape cod right now

 

Yeah just saw on my detector here.

[Clinch Leatherwood]

Yeah just saw on my detector here.

Only saw one bright flash, thunder was really delayed so it was nowhere close but first in a long time here