January 2015 Pattern Discussion

[ORH_wxman]

Gotta be careful how I phrase the question, but at this point what factors, if any, point toward the PV being dislodged in such a way that it would cause the NAO to go negative? Are there any current atmospheric parallels to the flip in 2005? Are there any current atmospheric parallels to 1994/95? Or, is it just plain different from either?

 

I'd like to know how the NH atmosphere looks today in comparison with those years.

 

We aren't going to know much fo anything about the chances of the NAO flipping until the first week of January. I'd suggest not worrying too much about it until we know how strong the stratospheric warming is in early January.

[40/70 Benchmark]

Yes. This season has certainly resembled more favorable El Ninos in the N PAC. We briefly broke down the AK ridging in December this year, but it has come back and looks to be with us for the foreseeable future.

 

The Atlantic has been putrid though, no sugar coating that. But years like 2004-2005 and 1957-1958 had similar Atlantic patterns early on but were able to flip it around. The difference is that 2004 was able to sneak in the 12/26 and early January snow events despite that Atlantic pattern...this year and 1957 were skunked.

 

I think we will rally this winter for sure in the snowfall deparment, but the NAO will probably be the difference between a 1957-1958 type rally and a more muted rally.

I agree 100%.

 

Another disparity between the background of this season, and those horror films the likes of 1995, is the configuration of the el Nino. Not only did 1995 have a vastly different November, which correlates to the winter in el Nino seasons, but the el Nino was strongly east based, while this one has become increasingly west based.

[CoastalWx]

The pacific pattern is also probably more conducive to helping a warming event as well, especially if heights lower in the Aleutians again.

[40/70 Benchmark]

The pacific pattern is also probably more conducive to helping a warming event as well, especially if heights lower in the Aleutians again.

I was just about to say that I believe the configuration of the el Nino and the overall Pacific regime, even the NAO, are all related, and I said as much in my outlook.

I'd be surprised if the NAO didn't budge.

[Damage In Tolland]

Well if that is the case plan on weeks long torches occurring at times this winter. EPO may not get it done alone and EPO and neg PNA is definitely possible at times.

We heard that last year and had no prolonged torches. Or really any for that matter

[weathafella]

We heard that last year and had no prolonged torches. Or really any for that matter

This year so far doesn't closely resemble last year or you'd be posting pics of your driveway snow piles or at least the shady side of your street.

[Damage In Tolland]

This year so far doesn't closely resemble last year or you'd be posting pics of your driveway snow piles or at least the shady side of your street.

The EPO was neggy all of last winter which is why December was a winter month and we had frigid snowstorm after frigid snowstorm . This year it's been POS until very recently. Hence the pattern change. 

[CoolMike]

The NAO currently sits at -1 SD.

 

Take a look at the CPC NAO chart.  Whats weird to me is the "sharpness" of the curve from today's observed NAO to the predicted future NAO for the next few days.  There is a discontinuity here in the analytic sense - ie - the curve is not smooth and is therefore non-analytic.

 

I'm not sure the very near term plays out exactly as predicted - I'd guess the observations come in much smoother than the predictions.

 

Edited to remove images which is now out of date.

[ORH_wxman]

That current -NAO is what's left of the ridging near Greenland/Iceland from the failed wave-breaking event on Christmas...the 12/27 system that went way NW of us sort of enhanced that ridge a little more...but this is all transient. We were hoping a week or two ago that the Xmas event would cause a big -NAO block and completely change the pattern in the Atlantic...but instead we got this brief transient ridge.

[Typhoon Tip]

The NAO currently sits at -1 SD.

 

Take a look at the CPC NAO chart.  Whats weird to me is the "sharpness" of the curve from today's observed NAO to the predicted future NAO for the next few days.  There is a discontinuity here in the analytic sense - ie - the curve is not smooth and is therefore non-analytic.

 

I'm not sure the very near term plays out exactly as predicted - I'd guess the observations come in much smoother than the predictions.

 

 

While the curve will probably verify a little "smoother", if you work your way back along the graph there are other inflections that were almost as sharp.  The index can change quite quickly.  Because of it's smaller domain size, perturbations rippling through the domain space can disrupt a signal across just a couple days in some cases where said disturbance is largely anomalous.  

 

I think the more impressive aspect about that graph is the tight agreement among the various ensemble members.  

[ORH_wxman]

Guidance is beginning to converge on our first legit arctic outbreak of the winter sometime in the Jan 5-7 range if we are counting the airmass later this week as more of a "glancing blow" of arctic air . The past couple of days has seen ensembles from multiple models trend in this direction.

 

Some guidance brings it in two waves...first around the 5th and then perhaps another wave around the 7th or 8th with a potential storm system in between in the northern stream...but those details are too far away to be worked out. The idea of some sort of arctic airmass affecting our region is looking pretty likely now. The EC ensemble mean has 850mb temps around -18C over the pike region in SNE at day 8. That is pretty impressive for that far out.

 

The strong -EPO block north of AK is driving this as the PV in Canada has nowhere to go.

[Typhoon Tip]

Guidance is beginning to converge on our first legit arctic outbreak of the winter sometime in the Jan 5-7 range if we are counting the airmass later this week as more of a "glancing blow" of arctic air . The past couple of days has seen ensembles from multiple models trend in this direction.

 

Some guidance brings it in two waves...first around the 5th and then perhaps another wave around the 7th or 8th with a potential storm system in between in the northern stream...but those details are too far away to be worked out. The idea of some sort of arctic airmass affecting our region is looking pretty likely now. The EC ensemble mean has 850mb temps around -18C over the pike region in SNE at day 8. That is pretty impressive for that far out.

 

The strong -EPO block north of AK is driving this as the PV in Canada has nowhere to go.

 

That's usually where the storm occur ... sort of at the book-ends of successive waves.  

 

almost like a quasi Archembault argument there. 

[weathafella]

The EPO was neggy all of last winter which is why December was a winter month and we had frigid snowstorm after frigid snowstorm . This year it's been POS until very recently. Hence the pattern change.

Look hemispherically. The pattern does not resemble last winter period. California is much wetter, niño regions are warmer, orientation of EPO is not the same, it's a different pattern beyond the slice of heaven called Tolland, CT.

[CoastalWx]

Just got a look at the models. They look pretty good IMO overall. Can't find a ton to complain about overall.

[CoastalWx]

Oh yeah, and As We Fooking Thought about the weeklies last week.  They looked suspicious and now changed their tune and keep ridging into western Canada through week 4. More of a +PNA look. We still have a +NAO and some SE ridging, but that look could be interesting. 

[TalcottWx]

5th-10th looks like the time when all systems go. Nothing much has changed with expecting that.

[CoastalWx]

The GEFS really want to keep ridging into AK while the EC had been weakening it and trying to build higher heights near and just off the west coast. Truth might be somewhere in between. Either way, you can see storminesss potential.

[CoastalWx]

Aside from inside runner potential, I like the overall look.  It's a high stakes pattern..kind of like last year at times. The cutters sucked, but the storms were fun. If we can get the ridge axis closer to the west coast, it could be money.  But it's likely we'll have at least one storm moving west of us or over us, so hopefully nobody complains. This includes the weekend.

[CT Rain]

Aside from inside runner potential, I like the overall look.  It's a high stakes pattern..kind of like last year at times. The cutters sucked, but the storms were fun. If we can get the ridge axis closer to the west coast, it could be money.  But it's likely we'll have at least one storm moving west of us or over us, so hopefully nobody complains. This includes the weekend.

 

I guess I'm a bit more concerned south of the Pike with the pattern. Should be fine C/N New England but I think we'll need a bit more luck for good snows. We certainly have a big risk for inside runners over the next couple weeks and given the monster +NAO it's not the most pleasant look. 

 

I could see us getting screwed south of the Pike for a while while places just north really cash in. 

Definitely has a cold look though in between said cutters. 

[40/70 Benchmark]

I guess I'm a bit more concerned south of the Pike with the pattern. Should be fine C/N New England but I think we'll need a bit more luck for good snows. We certainly have a big risk for inside runners over the next couple weeks and given the monster +NAO it's not the most pleasant look. 

 

I could see us getting screwed south of the Pike for a while while places just north really cash in. 

Definitely has a cold look though in between said cutters. 

Hopefully it won't too disheartening a period for those south of the pike.

[CoastalWx]

I guess I'm a bit more concerned south of the Pike with the pattern. Should be fine C/N New England but I think we'll need a bit more luck for good snows. We certainly have a big risk for inside runners over the next couple weeks and given the monster +NAO it's not the most pleasant look.

I could see us getting screwed south of the Pike for a while while places just north really cash in.

Definitely has a cold look though in between said cutters.

It probably will depend in how the overall ridge axis behaves heading into the 11-15 day. I guess for me, I just like seeing those highs even on an ensemble mean. It's tough to comment in the specifics this far out, but it does look stormy. Hopefully people understand the risks.

[BostonWX]

Hopefully it won't too disheartening a period for those south of the pike.

 

 

I think the pike region can cash in this setup. Certainly messy storms, but we should thump at least on the front ends in a pattern like this. I think the south coast is a different story and down through NYC.

 

[40/70 Benchmark]

I think the pike region can cash in this setup. Certainly messy storms, but we should thump at least on the front ends in a pattern like this. I think the south coast is a different story and down through NYC.

 

Yup.

[ORH_wxman]

I think the pike region can cash in this setup. Certainly messy storms, but we should thump at least on the front ends in a pattern like this. I think the south coast is a different story and down through NYC.

 

 

When talking about patterns, it's all about probabilities. N of pike is most likely to cash in, people further south are less and less likely the further south you go...but of course, we can't pretend that a storm couldn't pull a 1/21/14 and smoke the southern areas while we are choking on exhaust north of the pike...that's a detail that is impossible to forecast.

 

But given the propensity for a SE ridge in this pattern, we can say it is less likely you'd see that type of storm versus something that favors CNE/NNE.

[Damage In Tolland]

I guess I'm a bit more concerned south of the Pike with the pattern. Should be fine C/N New England but I think we'll need a bit more luck for good snows. We certainly have a big risk for inside runners over the next couple weeks and given the monster +NAO it's not the most pleasant look. 

 

I could see us getting screwed south of the Pike for a while while places just north really cash in. 

Definitely has a cold look though in between said cutters. 

Why would you post something like that? That leads to those posts from Ray who thinks he's in some kind of a special snow spot in this pattern and is going to jackpot lol

We aren't going to go snowless. I will say a place like BDL will get 8 inches or more by Jan 15th

[40/70 Benchmark]

Certainly NNE jackpots....no way I would.

I'm just happy to see a piece of the action.

 

I wish we could say the same is likely to be the case a bit to the south.

Hopefully we all get to share in.

[CT Rain]

Why would you post something like that? That leads to those posts from Ray who thinks he's in some kind of a special snow spot in this pattern and is going to jackpot lol

We aren't going to go snowless. I will say a place like BDL will get 8 inches or more by Jan 15th

 

It's a pattern discussion thread and this is part of the pattern.

 

I'm not terribly enthused about how this pattern looks for our area. I think once you get north of the Pike the pattern quickly turns quite good. With no blocking and a flexing SE ridge I think we risk a few inside runners. 

[Damage In Tolland]

It's a pattern discussion thread and this is part of the pattern.

 

I'm not terribly enthused about how this pattern looks for our area. I think once you get north of the Pike the pattern quickly turns quite good. With no blocking and a flexing SE ridge I think we risk a few inside runners. 

Well there is a difference though. I took it to mean you were thinking 0 snow the next couple weeks. Inside runners very often can lead to snow to ice events for us..similar to what we're looking at this weekend. Are we going to get copious amounts of snow in this pattern..probably not..but neither is anyone in SNE..If I was Dendrite on north I'd be amped for tons of snow. 

[BRSno]

January forecast on AccuWx has 21.4" for the month in BOS. Lock it in 

[CoastalWx]

Well there is a difference though. I took it to mean you were thinking 0 snow the next couple weeks. Inside runners very often can lead to snow to ice events for us..similar to what we're looking at this weekend. Are we going to get copious amounts of snow in this pattern..probably not..but neither is anon in SNE..If I was Dendrite on north I'd be amped for tons of snow. 

 

Really? LOL