January 2015 Pattern Discussion

[Damage In Tolland]

WPC

SLEET AND FREEZING RAIN WILL LIKELY TAKE UP

MORE REAL ESTATE THAN HERETOFORE THIS SEASON CONSIDERING THE HEFT
OF THE MODIFIED ARCTIC AIRMASS THAT SPREADS ACROSS THE MIDWEST AND
INTO THE MID ATLANTIC AND NORTHEAST MID- TO LATE WEEK. 

[CoastalWx]

Also, I agree with snowgoose that the +PNA might actually try to set up after the AK ridge retros out of the way. This could be from the tropical response.  You can see signs of that at the end of the run. At that point, it may become more Nino, but we may really play with fire if the NAO stays positive as a Nino pattern takes hold. 

[CoastalWx]

Even on the euro that so called "cutter" may be 12 hrs of warmth for cstl areas. 

[CoastalWx]

The GFS para uses that ULL over Hudsan Bay to create confluence and cause a snow event. While I think it's unlikely, something similar could cause a colder solution for the interior anyways.

[CT Valley Snowman]

What will need to occur in order to break down the + NAO

and get that SE ridge weaker?

[SnowGoose69]

Also, I agree with snowgoose that the +PNA might actually try to set up after the AK ridge retros out of the way. This could be from the tropical response.  You can see signs of that at the end of the run. At that point, it may become more Nino, but we may really play with fire if the NAO stays positive as a Nino pattern takes hold. 

 

I don't see how it won't stay positive, the tripole in the ATL blows donkey balls

[moneypitmike]

WPC

SLEET AND FREEZING RAIN WILL LIKELY TAKE UP

MORE REAL ESTATE THAN HERETOFORE THIS SEASON CONSIDERING THE HEFT

OF THE MODIFIED ARCTIC AIRMASS THAT SPREADS ACROSS THE MIDWEST AND

INTO THE MID ATLANTIC AND NORTHEAST MID- TO LATE WEEK. 

 

That's encouraging, but I'm always careful not to interpret the national discussions too specifically for MBY.  The states of the Mid-Atlantic include things like the high elevations of NC, the mountains of western VA, e.g.  The northeast encompasses more than New England.  I'm not saying we won't have some wintry stuff before what currently looks like a change to rain, but I recognize that definitions of terms like "the northeast" do not necessarily include the whole of New England--and in fact many times they do not.  Similarly, terms like the interior in a national discussion sometimes don't include GC where the statement is tied to PA/C-WNY/PF land.

 

I repeat, I'm not saying we won't have a little wintry stuff before what appears to be a change to rain, but I am careful how I interpret statements like what you posted.

 

39.0/37 at the Pit.  The horror show continues.

[CoastalWx]

I don't see how it won't stay positive, the tripole in the ATL blows donkey balls

 

The Atlantic is my problem. Without a good AK ridge..I get concerned we'll get garbage later in the month. I guess maybe it can stay massive and act as a confluence area, but I think that would really be walking the line. In any case, that's way out there.

[CoastalWx]

What will need to occur in order to break down the + NAO

and get that SE ridge weaker?

 

A nuclear bomb.

[SnowGoose69]

The Atlantic is my problem. Without a good AK ridge..I get concerned we'll get garbage later in the month. I guess maybe it can stay massive and act as a confluence area, but I think that would really be walking the line. In any case, that's way out there.

 

I think we can do pretty well if that PNA is positive most of the 2nd half of the winter with a -EPO and -AO.

[CoastalWx]

I think we can do pretty well if that PNA is positive most of the 2nd half of the winter with a -EPO and -AO.

 

Yeah, I just don't know if that would be a likely pattern for now.

[40/70 Benchmark]

I don't see how it won't stay positive, the tripole in the ATL blows donkey balls

The tripole is a reflection of the pattern. It looked great all summer into the fall, so why has the NAO been positive throughout the early part of the season? We need help from the stratosphere....then after the pattern changed, the tripole would start to reflect that. There is a feedback, so it probably helps to sustain it when there is no real driving force to change it, but the tripole is not the prevailing force

[CoastalWx]

The tripole is a reflection of the pattern. It looked great all summer into the fall, so why has the NAO been positive throughout the early part of the season? We need help from the stratosphere....then after the pattern changed, the tripole would start to reflect that. There is a feedback, so it probably helps to sustain it when there is no real driving force to change it, but the tripole is not the prevailing force

Bingo. Cold SSTs don't have the energy to force a pattern. They can feedback on it though.

[ORH_wxman]

I wouldn't over-analyze the 1/3-4 threat yet. It's 7 days out.

 

Every single system is going to have cut potential this far out without big ATL blocking....but there's also a lot of cold around, so it could end up more frozen if nuances in the ejection of vort energy changes.

[SnowGoose69]

The GFS para uses that ULL over Hudsan Bay to create confluence and cause a snow event. While I think it's unlikely, something similar could cause a colder solution for the interior anyways.

 

It also sends the system out in 2 distinct pieces more so...I would agree that the Para would even be overrunning snows down into NYC, the old GFS though definitely is a disaster for anyone wanting frozen.

[powderfreak]

Every single system is going to have cut potential this far out without big ATL blocking....but there's also a lot of cold around, so it could end up more frozen if nuances in the ejection of vort energy changes.

That pretty much sums it up. Could end up more frozen, could cut. Could thread the needle, or stab you.

[40/70 Benchmark]

The further south the poster is located the lower the melting temperature it seems.

They have less margin for error with the pattern.

[TauntonBlizzard2013]

Just took a look at the 6z para. Thats a nice way for everyone here to get a snowstorm on the 4/5.

Tough to go against euro and ensembles, but at this stage anything is possible

[SnowGoose69]

Just took a look at the 6z para. Thats a nice way for everyone here to get a snowstorm on the 4/5.

Tough to go against euro and ensembles, but at this stage anything is possible

 

The euro has been a dumpster fire this last month, I almost don't even trust it inside Day 4 right now.  I don't ever recall a stretch like this where the GFS was regular schooling the euro.

[trat]

Barry Burbank is still for an above normal snowfall.

[WinterWolf]

They have less margin for error with the pattern.

Exactly!!  I was also going to say, that their expectations are also lower for sustained bouts of Cold/wintry weather down in the Mid Atlantic.  Perhaps that is the better way to look at it....if our expectations are lower, we have less to be disappointed about.?? 

[40/70 Benchmark]

Exactly!!  I was also going to say, that their expectations are also lower for sustained bouts of Cold/wintry weather down in the Mid Atlantic.  Perhaps that is the better way to look at it....if our expectations are lower, we have less to be disappointed about.?? 

The ceiling is lower, but the envelope of what can be considered serviceable patterns is also less expansive.

That is what Jerry was alluding to, I think.

 

There is likely to be more angst generated by a sub par element of the pattern than there would be up here...ie, if the NAO is positive, then they are pretty much screwed, whereas we can still hope for safes in a gradient regime.

[ORH_wxman]

That pretty much sums it up. Could end up more frozen, could cut. Could thread the needle, or stab you.

 

 

That's the difficult part about not having blocking in the ATL...I mean, we saw the good and the bad last year with it. The good was February 2014...the bad was that 2 week strech in mid-January that gave us multiple cutters.

 

Our latitude helps with these systems, but sometimes it doesn't matter either. People just need to understand that it may not work out, but I'll take this pattern anyday over what we had for most of December. I'm enough versed in the statistics of it to understand that it doesn't mean we cash in either.

 

I also know that the deterministic hounds on here don't want to hear about probabilities or chances. They want to see snow on their front lawns.

[CoastalWx]

That's the difficult part about not having blocking in the ATL...I mean, we saw the good and the bad last year with it. The good was February 2014...the bad was that 2 week strech in mid-January that gave us multiple cutters.

 

Our latitude helps with these systems, but sometimes it doesn't matter either. People just need to understand that it may not work out, but I'll take this pattern anyday over what we had for most of December. I'm enough versed in the statistics of it to understand that it doesn't mean we cash in either.

 

I also know that the deterministic hounds on here don't want to hear about probabilities or chances. They want to see snow on their front lawns.

Right, exactly. We had a couple of decent events too in Jan. People want concrete yes or no answers, but sorry..it's a high stakes pattern. If you can't deal with probability, then you may want to leave the board.

[Typhoon Tip]

That's the difficult part about not having blocking in the ATL...I mean, we saw the good and the bad last year with it. The good was February 2014...the bad was that 2 week strech in mid-January that gave us multiple cutters.

 

Our latitude helps with these systems, but sometimes it doesn't matter either. People just need to understand that it may not work out, but I'll take this pattern anyday over what we had for most of December. I'm enough versed in the statistics of it to understand that it doesn't mean we cash in either.

 

I also know that the deterministic hounds on here don't want to hear about probabilities or chances. They want to see snow on their front lawns.

 

I agree with much of this ... but for the general reader I will also add:  there is a sneaky pattern type that has been in place really, for the past 7 to 10 days, where the negative expression of the PNAP has been dominating.

 

Perennial North American Pattern is defined as a shallow ridge amplitude over the Rockies, coupled with equal shallow trough in the east.  It's considered the base-line structure over N/A, and it is mathematically shown for having the topography under a west flow that this continent has. In fact, any land mass that imposes a cordillera against a wind field will torque the flow as such.. .

 

But that's not the point I'm making ... This -PNAP has a ridge OFF the west coast, and that means two things:

 

1) the flow split tendency is large.

 

2) the L/W axis after the split has two waves; one over SE Canada; the other in the deep SW.  These two features in that position relative to one another are in "deconstructive" wave interference.  

 

The persistence of the above state means exactly (still) what it meant last week when I posted the statement, cold is above median probability for occurrence, major precipitation events are below.  

 

Now someone's going to argue that the deal modeled for D7 denies that conclusion ... but that's short sighted if so.. Because none of the above precludes a fast moving event -- they are off-sets/hinderances.  Not physical limitations.   Fact of the matter is, that event has to happen because so much dynamics get left behind and eventually ejected, that there is enough to conserve as it lifts through the fast fast fast flow. Otherwise, if you look at other small perturbations in the flow that get ejected prior to that bigger event, they demo all this nicely by literally just disappearing before they make 80W.  

 

Anyway, ...Still... since before well before Xmas, nothing has really changed. We're still brow beating but until we break this puppy down and herald in the new paradigm, folks may as well engage in there other hobbies ... otherwise you may be in for a tedious vacuum in non-and-or-uninteresting events.

 

Now watch ... the GGEM hinted ice storm cripples us. Ha ha.  Oy vay -  

[weathafella]

Euro is going different for 1/3-4.

[CoastalWx]

Euro is going different for 1/3-4.

 

LOL, just a bit. Again, this is difficult for models to handle.

[weathafella]

LOL, just a bit. Again, this is difficult for models to handle.

Can't say I don't like this solution better though..lol.

[weathafella]

Extended school vacation on the euro.

[ORH_wxman]

Its a good example of how small nuances in the ejection of the southwest energy can cause large differences in the sensible wx.