January 2015 Pattern Discussion

[Isotherm]

In this Washington post article from a couple months ago, Cohen stated this:

 

"Typically the [fall Eurasian] snow signal doesn’t arrive [or manifest itself] in North America until sometime in January. So based on [fall Eurasian] snow cover alone, the forecast from January through March is clearer. So for years with high snow cover [like this one], I expect the period from late  January through March to be colder than December through early-to-mid January. There have been some great examples of this recently but especially 2012-13."

 

http://www.washingtonpost.com/blogs/capital-weather-gang/wp/2014/12/02/why-prosperous-autumn-snows-in-eurasia-may-portend-a-brutal-east-coast-winter/

 

 

So it sounds like the forecast will always be trickier AO wise for the first half of winter. I doubt he anticipated the magnitude of the +AO (nor did anyone), but the initiation of the -AO now would be in line with the snow cover method according to him.

[ORH_wxman]

In this Washington post article from a couple months ago, Cohen stated this:

 

"Typically the [fall Eurasian] snow signal doesn’t arrive [or manifest itself] in North America until sometime in January. So based on [fall Eurasian] snow cover alone, the forecast from January through March is clearer. So for years with high snow cover [like this one], I expect the period from late  January through March to be colder than December through early-to-mid January. There have been some great examples of this recently but especially 2012-13."

 

http://www.washingtonpost.com/blogs/capital-weather-gang/wp/2014/12/02/why-prosperous-autumn-snows-in-eurasia-may-portend-a-brutal-east-coast-winter/

 

 

So it sounds like the forecast will always be trickier AO wise for the first half of winter. I doubt he anticipated the magnitude of the +AO (nor did anyone), but the initiation of the -AO now would be in line with the snow cover method according to him.

 

 

Yeah you could give at least a partial mulligan for December...but January is going to come in solidly positive. He can save the forecast a bit if Feb/Mar are strongly negative.

[mahk_webstah]

No "Congrats Dendrite" the next 7 days.

 

And it isn't looking great for anyone on here really.  When is our next chance of a truly region wide SNE CNE even a good bit of NNE?  I suspect that is now February.  We haven't been talking much long range with this stuff in the short range.  Looking at HPC Hemispheric, +NAO roaring through day 6 and then diffuse neutral looking day 7.  Western Ridging well up towards the pole in Western Canada - looks strong and steady.

[CoastalWx]

Pattern looks rather active heading into Feb with multiple chances for snow.

[Ginx snewx]

We don't tosshttp://www.aer.com/science-research/climate-weather/arctic-oscillation

[Typhoon Tip]

.

Wow... I took three days away to focus on work and just like that... I'm looking at perhaps three storms threats over the next 10 days. 

 

Oh, and by the way: underscoring the point I was making a month ago about the 130W ridge axis being all wrong... The NAO remains turdly but notice the ridge in the W. has repositioned in the Rockies longitude and viola!  

 

Much better for storm enthusiasts.   I do think there is too much emphasis placed on the NAO, when it is just another variable/teleconnector that can assist or serve detrimental.    

[powderfreak]

I do think there is too much emphasis placed on the NAO, when it is just another variable/teleconnector that can assist or serve detrimental.

Season to date, if there was a negative NAO in the means, SNE probably would be having one heck of a snow season so far. Might have even shafted us though as we seem to be just far enough NW with some of the inside runners, but I don't think there's excess emphasis put on how important a -NAO would've been to SNE or the mid-Atlantic so far this season.

[J Paul Gordon]

Models seem to keep us plenty cold for the foreseeable future.... even when it milds up in the midwest. Is there a reason for this? Or, am I simple misreading them? 

[mahk_webstah]

Models seem to keep us plenty cold for the foreseeable future.... even when it milds up in the midwest. Is there a reason for this? Or, am I simple misreading them? 

-EPO I think, keeps dumping cold into the east

[Damage In Tolland]

Was the past week which supposedly was the "thaw" above or below normal?

[ORH_wxman]

Early February is looking brutally cold.

[Damage In Tolland]

So was the last week at the big 4 An or BN? Just the past 7 days

[ORH_wxman]

So was the last week at the big 4 An or BN? Just the past 7 days

 

 

Start on Sunday since Saturday was that last brutal cold shot. There was a thaw but it was really weak...we thought it would be once we got closer.

 

ORH including today has done this for departures the past 6 days starting Sunday:

 

+9, +7, +2, 0, +4, -1

[CoastalWx]

Ponds completely iced over all month. Tough to do in the BOS area. 

[Clinch Leatherwood]

Ponds completely iced over all month. Tough to do in the BOS area.

Great stretch of winter already is upon us. So many had so little faith.

[CoastalWx]

Great stretch of winter already is upon us. So many had so little faith.

 

I just don't want to go into this cold again without some snow. It drives me nuts. Hopefully a few tomorrow and a bit Monday night.

[weathafella]

Ponds completely iced over all month. Tough to do in the BOS area.

Charles frozen all the way to the science museum.

[Damage In Tolland]

The cold the Euro is showing for days 8-10 is ridiculous. I mean if that verifies..that's like single digits for highs

[RUNNAWAYICEBERG]

The cold the Euro is showing for days 8-10 is ridiculous. I mean if that verifies..that's like single digits for highs

With a very healthy pack, coldest of season.

[CT Valley Snowman]

Hey.. I hope your super snowy next 8 weeks are correct .. We all do. But as of now I'm expecting to finish with less than 40 inches of snow here. I see lots of C&D

This was another good one.

[Damage In Tolland]

This was another good one.

How come you are doing this?

[CT Valley Snowman]

How come you are doing this?

Reliving the past winter after Ginxy post in February thread. Just having fun. You and Ray had some really good ones.

[Ginx snewx]

Reliving the past winter after Ginxy post in February thread. Just having fun. You and Ray had some really good ones.

awesome thread

[Typhoon Tip]

Season to date, if there was a negative NAO in the means, SNE probably would be having one heck of a snow season so far. Might have even shafted us though as we seem to be just far enough NW with some of the inside runners, but I don't think there's excess emphasis put on how important a -NAO would've been to SNE or the mid-Atlantic so far this season.

 

This may be old hat at this point.  Someone bumped this thread and brought this to my attention... 

 

But the -NAO ...as I was trying to point out, was not as culpable in assisting the cold necessary for the big snows of SNE last year.  

 

I don't argue that the -NAO helps - that was never in dispute. But simply that it's application is overrated, and that gets proven all the time ... yet, you have these various Met pundits/and/or media outlooks throwing up headlines for it way too often and they don't really know how the domain space mass-field's alterations and phase states really effect the NE CONUS weather.  The current understanding only gets people 60% (or so..) of how it all works. 

[Ginx snewx]

This may be old hat at this point. Someone bumped this thread and brought this to my attention...

But the -NAO ...as I was trying to point out, was not as culpable in assisting the cold necessary for the big snows of SNE last year.

I don't argue that the -NAO helps - that was never in dispute. But simply that it's application is overrated, and that gets proven all the time ... yet, you have these various Met pundits/and/or media outlooks throwing up headlines for it way too often and they don't really know how the domain space mass-field's alterations and phase states really effect the NE CONUS weather. The current understanding only gets people 60% (or so..) of how it all works.

as stated in this thread , in a highly negative EPO state, transient blocking is as effective. Temporary neg NAO type conditions work just fine.

[CoastalWx]

The snow blitz was really +PNA driven. No way in hell we would have had that with a more -EPO.

[ORH_wxman]

The snow blitz was really +PNA driven. No way in hell we would have had that with a more -EPO.

 

 

Yeah we can get good cold with the -EPO, but by itself, it won't produce big snows. Just look at the 500mb composites of many of the 1980s winters.

 

We had an almost perfectly placed PNA ridge that stayed somewhat stangent for 2-3 weeks with only a brief relaxation which occurred around the time of the the Feb 7-9 long duration snow event...where most of the country was furnacing yet we stayed in our own little protective cocoon of deep winter. We got lucky on that one...we gave back a bit of our luck in March though. That pattern probably should have produced more than it did.

 

 

So it was definitely a combo of the EPO and PNA...but for the snowfall, the PNA was the bigger driver. EPO really drove the frigid air...it probably helped us the most in the Feb 7-9 event.

[CoastalWx]

Yeah we can get good cold with the -EPO, but by itself, it won't produce big snows. Just look at the 500mb composites of many of the 1980s winters.

 

We had an almost perfectly placed PNA ridge that stayed somewhat stangent for 2-3 weeks with only a brief relaxation which occurred around the time of the the Feb 7-9 long duration snow event...where most of the country was furnacing yet we stayed in our own little protective cocoon of deep winter. We got lucky on that one...we gave back a bit of our luck in March though. That pattern probably should have produced more than it did.

 

 

So it was definitely a combo of the EPO and PNA...but for the snowfall, the PNA was the bigger driver. EPO really drove the frigid air...it probably helped us the most in the Feb 7-9 event.

 

A more -EPO also increases the risk of cutters if you get that good ridge breaking into AK that shoves shortwaves south into the Plains and then amplifies. I mean don't  get me wrong..I would take a -EPO for a good winter and run with it, but that snow blitz was a beautiful display of perfectly placed ridging out west...and of course a little pixy dust sprinkled on top.

[ORH_wxman]

A more -EPO also increases the risk of cutters if you get that good ridge breaking into AK that shoves shortwaves south into the Plains and then amplifies. I mean don't  get me wrong..I would take a -EPO for a good winter and run with it, but that snow blitz was a beautiful display of perfectly placed ridging out west...and of course a little pixy dust sprinkled on top.

 

 

PNA ridge was skewed a bit east over the N Rockies...that is pretty much dead perfect for eastern New England. A Boston-optimized pattern....it sticks the trough far enough east so that you are either getting buried or scrapers/late bloomers/whiffs...no cutters in that pattern. And yeah, notice how the blocking up north is more in the WPO region...it's still a negative EPO but only mildly to moderately.

 

[Ginx snewx]

I would argue a strictly PNA driven pattern without EPO would not allow for the transient block to set up, Jan 27th storm. Many here as seen in this thread previously refused to believe transient blocking was as effective as Neg NAO.