Ending out December with a Potential Pattern Change

[40/70 Benchmark]

Ray, what are your two new analogs? I'm guessing '99-'00 is one of them even though that was not a Nino. That had a fun period during Jan. My guess for the other would be some random 80's winter that I know nothing about lol.

No way ...nothing like that. No need to go there as of yet, but it would just imply toning things down a notch or two.

[mahk_webstah]

The chances of it being strong and cutting over DET are very low. The pattern right now is not one for big , wound up storms.

 

This is also why when you piss away the month of December that you can't have an epic winter. You lose a full month and are only left with 2 possible good ones.

The pattern change that we want is producing the strong wound up storm.  I didn't say large storm over Detroit...you were arguing no phase.

 

We probably need the pattern change storm, as Scott has been suggesting.  It is the modelled change in Pacific flow that produces a good wound up storm. We need that to happen as it reshuffles the deck.  Root for the stem winder.  If it somehow is able to redevelop off the coast before flooding us with warmth that would be cool.  Would be awesome if some blocking/confluence would form to our north and east and force damming or redevelopment, but wouldn't that interfere and slow down the pattern change?

 

Very frustrating.  15-20 miles to my NW it is very wintery with 6-12 on the ground and in the trees.  I thought we'd have 4 feet by Jan 1, that is looking tough as we only have 20 now.

[CoastalWx]

The Christmas storm doesn't have a whole lot

To do with whatever happens this weekend. Euro had a decent storm yesterday and it still sucked.

[Damage In Tolland]

The pattern change that we want is producing the strong wound up storm.  I didn't say large storm over Detroit...you were arguing no phase.

 

We probably need the pattern change storm, as Scott has been suggesting.  It is the modelled change in Pacific flow that produces a good wound up storm. We need that to happen as it reshuffles the deck.  Root for the stem winder.  If it somehow is able to redevelop off the coast before flooding us with warmth that would be cool.  Would be awesome if some blocking/confluence would form to our north and east and force damming or redevelopment, but wouldn't that interfere and slow down the pattern change?

 

Very frustrating.  15-20 miles to my NW it is very wintery with 6-12 on the ground and in the trees.  I thought we'd have 4 feet by Jan 1, that is looking tough as we only have 20 now.

I'll go out on a limb and say we don't even get a cutter..more of a weak low that goes from mix to rain and temps in the 30's.

[mahk_webstah]

that is a thin limb but you are super lean so who knows?

[Hazey]

I think we almost need a whopper of a cutter just to re shuffle the deck. It just sucks that it happens to be at the worst time. Oh well.

[weathafella]

We haven't had wound up storms? Well I suppose if you discount the one last week and thanksgiving lol..

[CoastalWx]

We haven't had wound up storms? Well I suppose if you discount the one last week and thanksgiving lol..

Yeah, QPF out the ass.

[ORH_wxman]

65" is a figure that's been accomplished in 19 of the 124 seasons on record at BOS(By my quick skim of the totals column, might have missed a year or two but that's about right), so right around 15%, yeah maybe a bit too high of a percentage for blockbuster(Didn't go back through and count, but I'd guess going to 70" would knock about half of those out), but certainly a top tier winter IMO.

 

Now, when you get inland, and climo is right around 70", 150%(105" at ORH), is a blockbuster, only two winters have ever passed the 105" mark there(1992-93 and 2004-2005), two more are between 100" and 105". Goes back to a discussion earlier in the season about how interior is generally going to be closer to climo on the whole on both extremes, while the coastline can be really really bad and also really really good relative to climo.

 

 

ORH has had 5 winters greater than 105"

 

1. 1995-1996...132.9"

2. 1992-1993...120.1"

3. 2002-2003...117.3"

4. 2004-2005...114.3"

5. 2012-2013...108.9"

 

1960-1961 was close at 104.3"

 

 

But I agree I'd consider 105" a blockbuster at ORH.

[Baroclinic Zone]

Just hold my hand, and I will guide you through. All part of the plan.

How soon before we start seeing PV of Death pop up in the media?

[CoastalWx]

How soon before we start seeing PV of Death pop up in the media?

I joked last week saying we may see it.

Well as far as Christmas, that's really tough. Yes it is 8 days out but the airmass is already marginal leading up to it. It would have to bomb SE of the cape. Even with a -NAO, all you are doing is rotating garbage in. Maybe it can drift east and flip for some, but it doesn't look pretty. That is storm 2 of potentially 3 messy transition lows. The third has a much better chance of frozen. Maybe another near NY as we are plenty cold.

[Damage In Tolland]

Yeah, QPF out the ass.

Plenty of precip for sure..but not big wound up storms

[CT Valley Snowman]

that's a pretty big South East Ridge on the day 10 euro op, if that were to verify the next storm after Christmas could be a rainer as well. hopefully that will change

[weathafella]

Plenty of precip for sure..but not big wound up storms

Wasn't last week a big cutoff that created gobs of qpf and tons of wind?

[40/70 Benchmark]

It was Will that said 120-150% OF CLIMO is a reasonable expectation and I agree, esp in ern areas. I still feel good with the euro seasonal showing a nice JFM pattern. The only reason why I brought this up was to say that if the area (esp inland) is somehow snowless into NY, then a true blockbuster may be off the table. A blockbuster meaning the top echelon of winters. I wasn't suggesting anything otherwise. I just want to get that out there.

This.

[Damage In Tolland]

Wasn't last week a big cutoff that created gobs of qpf and tons of wind?

Offshore sure..but what i mean is we haven't seen any big wound up cutters..There's been plenty of coastals yes. 

 

The pattern  now isn't conducive for monster GL lows..That's why you lean weaker and colder for Xmas storm..meaning mix/cold rain..maybe snow up north

[CT Valley Snowman]

I guess if you look at 50 degrees and rain vs 35 degrees and rain as somewhat of a moral victory then that is great but otherwise it is still disappointing

[CoastalWx]

You guys are predictable.

[mreaves]

You guys are predictable.

I just have one question for you.  Based on your prediction that winter is basically over, should I refill my pool?  I'll wait for your answer.  Thanks in advance.

[CT Valley Snowman]

once a weenie always a weenie

[JC-CT]

I understand what you mean about 12/31 vs 1/1, but the point myself, Will , and others have said, is that it's important to have money in the bank going into January if you really want a blockbuster winter. Plenty of great winters have happened along the coast without that though.

I'm going to continue this convo here.

I have always been under the impression that blockbuster winters are largely a function of blockbuster storms. If you can get half of your blockbuster total in two storms that occur in Jan and Feb, I don't think it matters much if you get 8-10" vs 2-4" in December.

[Baroclinic Zone]

There is nothing stopping the modeled system from amplifying up into the GL for Christmas Eve.  Only saving grace would be if the ridging out west occurs further east.  But typically cutters gonna cut.

[CT Valley Snowman]

looks beautiful down here in New Haven Connecticut. The Sun is coming out and its already in the 40's, nice green grass in spots from all the rain they've been having down here. feels like spring

[mahk_webstah]

Offshore sure..but what i mean is we haven't seen any big wound up cutters..There's been plenty of coastals yes. 

 

The pattern  now isn't conducive for monster GL lows..That's why you lean weaker and colder for Xmas storm..meaning mix/cold rain..maybe snow up north

Lol.

Right now, at this moment, the pattern isn't conducive for a wound up cutter....maybe that is why we aren't having one today or tomorrow or the next day.  But a lot of model data showing changes in the Pacific in a few days (not 7-10) suggests we will be ready for a big wound up storm, with a good chance of that being in the Ohio Valley.  This is part of a pattern change process that you have seen for 40 years - remember?

[Mike.Ventrice]

My 6-10 and 11-15 day period discussions from this morning: 

 

Models have rounded into better agreement this morning, all of which may be contributed to a local cyclonic wave breaking event setting up over the eastern U.S. during the latter half of the 6-10 day period forecast. Models often struggle with these wave breaking events and they have been clearly struggling over the past week as the forecast continues to trend warmer over the East. The latest models are moving away from the idea of a strong coastal "Nor'easter" to impact the coastal east and towards the idea of a major winter storm to impact the Midwest as a highly-anomalous upper-level cold trough digs across the central U.S. The change of pattern is clearly being driven by upstream processes over the Pacific Ocean. We have been locked into an El Nino driven pattern for the good portion of this month. That pattern will be ending during the 6-10 day period forecast, in response to a very deep upper-level cold trough sliding off the coast of Asia, forcing a high-latitude wave anticyclonic breaking event over the North Pacific. This event will result in warm upper-level ridge development over Alaska mid-to-late period, tanking the East Pacific Oscillation (EPO) into negative territory. A direct downstream response will be felt over the U.S., in which some colder air from the north will be able to freely flow down the Rockies and fuel the explosive deepening of a mid-latitude cyclone aiming to take shape over the Midwest and Ohio Valley. The details remain to be panned out, but the synoptic set up is favoring for strong dynamical forcing that results in a winter storm across the major markets in PJM mid-to-late period. A flux of moist tropical air from the east will fuel the system. This plume of mild, moist Atlantic air will result in unseasonably mild temperatures across the Northeastern U.S. around Christmas, setting up a possible heavy rain event for DCA, PHL, NYC in through BOS.

Now while the 6-10 day period forecast has trended warmer in response to this upcoming cyclonic wave breaking event, this particular event (in addition to the upstream forcing) is setting the stage for a major pattern change during the 11-15 day period forecast. With the massive cyclone to spin across the Great Lakes and up through eastern Canada late in the period, it will aid in advecting a highly anomalous cold air mass down the western two thirds of the nation, resulting in well below average temperatures to flood the western two thirds of the nation. We typically see major pattern transitions across the lower 48 following the development a significant mid-latitude cyclone, and this is the anticipated pattern evolution heading into the final week of the month.

 

11-15 day:

 

A period of cold weather and high heating demand is anticipated during the 11-15 day period forecast. High latitude blocking will be the theme during late December in through January, with a prominent upper-level warm ridge forecast to spin up over Alaska and build northward in through the North Pole and eastern Siberia. This pattern sets will generate cross polar flow from Siberia in through the U.S. during the time frame, sponsoring a period of well below average temperatures from the Pacific Northwest Basin in through the eastern two thirds of the nation. We have seen a significant shift in the ECMWF EPS towards the GFS model package solution, in which the model is now more aggressive with building a western U.S. ridge and deepening and eastern U.S. trough as heights build across the North Pole. A split of the tropospheric "Polar Vortex" looks prominent, which a lobe will likely spin down across the Hudson Bay and facilitate cold northwesterly flow on its western flank. Coast to coast cold weather will be the rule during the 11-15 day period forecast, impacting all major markets in the U.S. with exception of those in the Southwest. 

Now while the state of convection in the tropics, specifically the Madden Julian Oscillation (MJO) is headed for the "Warm USA" phases, it will have no impact on the U.S. pattern as high-latitude blocking will set up over the North-Northeast Pacific, driving a series of arctic air masses down across the U.S. The pattern looks extremely similar to what was observed last winter or back in November, and we should expect a similar outcome... Cold temperatures and increased heating demand. Now while there will likely be some details that remain to be panned out in response to synoptic waves (winter storms) spinning around the U.S., we hold higher than average confidence in the upcoming pattern change that will end in winter-type conditions across the lower 48.

[Mike.Ventrice]

Also, for those interested in the stratosphere... I tweeted this out this morning.

 

https://twitter.com/WSI_Energy/status/545185382602924034

[CoastalWx]

I'm going to continue this convo here.

I have always been under the impression that blockbuster winters are largely a function of blockbuster storms. If you can get half of your blockbuster total in two storms that occur in Jan and Feb, I don't think it matters much if you get 8-10" vs 2-4" in December.

Well those happen more frequently on the coast. It's easy to do that when you avg 45". But even 2012-2013 couldn't do that in Boston. Logan fell well short of 70". So it gets very hard to do if you have to go that route. Boston was close in 2010/2011 before we ran out of gas.

I'll say it again though. I'm not saying it's impossible, nobody is canceling winter, and I would say the chances of a moderate event in the interior between now and 1/1 are >50%. I still feel

good about this winter. I always have.

[JC-CT]

Well written Mike.

[CoastalWx]

Also, for those interested in the stratosphere... I tweeted this out this morning.

https://twitter.com/WSI_Energy/status/545185382602924034

Talked to HM about that yesterday. Even at 50mb it's showing signs of elongation and splitting near North Pole. Granted it's been "bend don't break" lately but a nice sign hopefully.

[JC-CT]

I still feel

good about this winter. I always have.

So do I, but I was just saying that holds true even if I don't end up with another measurable snowfall in January as long as the pattern looks good.

A bad December can be made up for with a good first couple weeks of March. Kevin would disagree from a psychological perspective, but I just mean seasonal total.