Next week's storm, Changes, Snow threats beyond (Part 2)

[OKpowdah]

Figured we should get a new thread going during the evening model lull.

So, very much to discuss:

1) Thursday 1/12 (one year anniversary of much rejoicing)

-- Significant trough diving into the Northern Plains, while a cutoff low lifts northeastwards toward the region.

Pretty big differences remain in model guidance with respect to the amplitude of the diving trough and the track of the cutoff.

Regardless: Big precipitation and wind event for New England.

Some question remains re: wintry potential for interior CNE and NNE ... a couple opportunities: first in advance of the cutoff low, and next with a s/w embedded in the large trough ... as the Euro alluded to, maybe a late blooming Miller B that throws some moisture back into the cold airmass blasting into the region (read on).

2) CAA behind the storm

Decent blast of cold air, as the trough digs into the Great Lakes and swings through New England.

Again, much disagreement with that trough, which just amplify through the end of the week.

3) Storm threat next weekend circa 1/14

-- Model differences ... to break it down simply ... three disturbances:

...1. the big trough moving through the region, and lifting northward

...2. model guidance has trended toward cutting off a piece of energy diving south with the big trough next week. So that should be fun to resolve.

Normal biases apply ... the Euro cuts it off west of southern California; the GFS further east, and the Canadian never cuts it off as it is overwhelmed by the bowling ball that it makes of the trough next week.

...3. incoming northern stream s/w behind the big trough.

So questions as to phasing of the northern s/w and the new cutoff, as well as the evolution of the big trough, which seems to pose huge questions for the end of next week.

4) Pattern change? Storm threats?

-- Signs that ridging building from the Aleutians northward definitely breaking up the polar vortex fairly efficiently.

Still looks like a fairly classic gradient pattern unfolding, with the states of the PNA and NAO affecting the orientation of the gradient and storm tracks.

Questions to the legitimacy of the pattern change, and will it hold?...Closely watching heights over Alaska...

At the very least, we're definitely taking care of the AO domain fairly well.

Also, watching for a possible major stratospheric warming in the next 10 days.

[CT Rain]

Figured we should get a new thread going during the evening model lull.

So, very much to discuss:

1) Thursday 1/12 (one year anniversary of much rejoicing)

-- Significant trough diving into the Northern Plains, while a cutoff low lifts northeastwards toward the region.

Pretty big differences remain in model guidance with respect to the amplitude of the diving trough and the track of the cutoff.

Regardless: Big precipitation and wind event for New England.

Some question remains re: wintry potential for interior CNE and NNE ... a couple opportunities: first in advance of the cutoff low, and next with a s/w embedded in the large trough ... as the Euro alluded to, maybe a late blooming Miller B that throws some moisture back into the cold airmass blasting into the region (read on).

2) CAA behind the storm

Decent blast of cold air, as the trough digs into the Great Lakes and swings through New England.

Again, much disagreement with that trough, which just amplify through the end of the week.

3) Storm threat next weekend circa 1/14

-- Model differences ... to break it down simply ... three disturbances:

...1. the big trough moving through the region, and lifting northward

...2. model guidance has trended toward cutting off a piece of energy diving south with the big trough next week. So that should be fun to resolve. Normal biases apply ... the Euro cuts it off west of southern California; the GFS further east, and the Canadian never cuts it off as it is overwhelmed by the bowling ball that it makes of the trough next week.

...3. incoming northern stream s/w behind the big trough.

So questions as to phasing of the northern s/w and the new cutoff, as well as the evolution of the big trough, which seems to pose huge questions for the end of next week.

4) Pattern change? Storm threats?

-- Signs that ridging building from the Aleutians northward definitely breaking up the polar vortex fairly efficiently.

Still looks like a fairly classic gradient pattern unfolding, with the states of the PNA and NAO affecting the orientation of the gradient and storm tracks.

Questions to the legitimacy of the pattern change, and will it hold?...Closely watching heights over Alaska...

At the very least, we're definitely taking care of the AO domain fairly well.

Also, watching for a possible major stratospheric warming in the next 10 days.

Good post. I think with this major ridging/blocking over the Bering Strait wer'e finally able to get rid of the +AO. With strong stratospheric warming that is probably a good sign that the +AO regime won't come back.

I do think the retrograding Aleutian ridge/block is going to cause some problems for most of CONUS with the +EPO returning. I'm fairly confident that happens.

With a +EPO/-AO (or AO neutral) pattern we'll definitely have some chances. What's intriguing to me is that even looking at the op GFS run through D16 southern stream energy is basically non-existent. Not a classic "gradient" pattern in that sense with shortwaves ejecting from 4 corners region.

Thoughts?

[Tropopause_Fold]

it's interesting (or something?) that of the 18z gefs members that do have a follow up storm for late week...nearly all members that have it are a warm cutter.

[OKpowdah]

Good post. I think with this major ridging/blocking over the Bering Strait wer'e finally able to get rid of the +AO. With strong stratospheric warming that is probably a good sign that the +AO regime won't come back.

I do think the retrograding Aleutian ridge/block is going to cause some problems for most of CONUS with the +EPO returning. I'm fairly confident that happens.

With a +EPO/-AO (or AO neutral) pattern we'll definitely have some chances. What's intriguing to me is that even looking at the op GFS run through D16 southern stream energy is basically non-existent. Not a classic "gradient" pattern in that sense with shortwaves ejecting from 4 corners region.

Thoughts?

Relating to the patterns in 2007-9 ... an active southern stream depended on split flow downstream of a -EPO ridge, diving into a -PNA trough (with the northern stream directed southeast into the Northern Plains)... I think it might have been you who mentioned the attractiveness of some degree of -PNA for storm opportunities here in a gradient pattern like this ... classic SWFE set ups in that situation. Otherwise, the La Nina doesn't support much southern stream activity when it sits alone.

One thing that's nice to see with some of the recent GFS runs is that even with a re-emerging +EPO, the flow remains amplified, attributable to the falling AO ... so we're at least not stuck back in this raging zonal jet unimpeded across a full latitude circle.

[Tropopause_Fold]

one thing that seems like a solid bet right now...is cold air dumping on to this side of the pole thanks to the aforementioned ridging in the north pacific...how far south it gets remains a question but:

[mahk_webstah]

Good post. I think with this major ridging/blocking over the Bering Strait wer'e finally able to get rid of the +AO. With strong stratospheric warming that is probably a good sign that the +AO regime won't come back.

I do think the retrograding Aleutian ridge/block is going to cause some problems for most of CONUS with the +EPO returning. I'm fairly confident that happens.

With a +EPO/-AO (or AO neutral) pattern we'll definitely have some chances. What's intriguing to me is that even looking at the op GFS run through D16 southern stream energy is basically non-existent. Not a classic "gradient" pattern in that sense with shortwaves ejecting from 4 corners region.

Thoughts?

Ryan, would that be a general retrogressive pattern with other features doing same? i.e. the natl ridge and the greenland vortex?

[weathafella]

Who's up for a few days in Aroostook County? Hotels..some pretty nice...and not expensive and among the few laces in the lower 48 getting winter.

[HoarfrostHubb]

Who's up for a few days in Aroostook County? Hotels..some pretty nice...and not expensive and among the few laces in the lower 48 getting winter.

Riding the sleds with Toot FTW

Hopefully in a few weeks you will be able to snowmobile or XC ski down Comm Ave

[CoastalWx]

Relating to the patterns in 2007-9 ... an active southern stream depended on split flow downstream of a -EPO ridge, diving into a -PNA trough (with the northern stream directed southeast into the Northern Plains)... I think it might have been you who mentioned the attractiveness of some degree of -PNA for storm opportunities here in a gradient pattern likPe this ... classic SWFE set ups in that situation. Otherwise, the La Nina doesn't support much southern stream activity when it sits alone.

One thing that's nice to see with some of the recent GFS runs is that even with a re-emerging +EPO, the flow remains amplified, attributable to the falling AO ... so we're at least not stuck back in this raging zonal jet unimpeded across a full latitude circle.

If we can get that cut off block to hang near AK that could be good despite the +EPO. That EPO is my worry but that will be block dependent. It could also cause a lot of angst within a short distance around these parts lol, in terms of latitude.

[CT Rain]

Relating to the patterns in 2007-9 ... an active southern stream depended on split flow downstream of a -EPO ridge, diving into a -PNA trough (with the northern stream directed southeast into the Northern Plains)... I think it might have been you who mentioned the attractiveness of some degree of -PNA for storm opportunities here in a gradient pattern like this ... classic SWFE set ups in that situation. Otherwise, the La Nina doesn't support much southern stream activity when it sits alone.

One thing that's nice to see with some of the recent GFS runs is that even with a re-emerging +EPO, the flow remains amplified, attributable to the falling AO ... so we're at least not stuck back in this raging zonal jet unimpeded across a full latitude circle.

Yes, that is a very good sign.

I think the -PNA pattern is going to be important for us to get some storminess. But as modeled the southern stream appears nearly dormant. May allow for some interesting redeveloping clippers but in general I think it's a relatively dry pattern.

[Ginx snewx]

Who's up for a few days in Aroostook County? Hotels..some pretty nice...and not expensive and among the few laces in the lower 48 getting winter.

LOL on the laces, lovely lasses with laces?

[CT Rain]

If we can get that cut off block to hang near AK that could be good despite the +EPO. That EPO is my worry but that will be block dependent. It could also cause a lot of angst within a short distance around these parts lol, in terms of latitude.

Tolland FTL

Mt. Socks FTW

[Tropopause_Fold]

Yes, that is a very good sign.

I think the -PNA pattern is going to be important for us to get some storminess. But as modeled the southern stream appears nearly dormant. May allow for some interesting redeveloping clippers but in general I think it's a relatively dry pattern.

ryan - are you writing these two thoughts exclusive from one another?

[CT Rain]

ryan - are you writing these two thoughts exclusive from one another?

Yeah... sorry didn't make much sense the way I wrote it.

I think the -PNA pattern is a plus in making sure we can ride the gradient and have some fun with storminess. However, as modeled, the southern stream looks pretty dull.

[CT Rain]

GFS has a nice looking active northern stream. The lack of upstream blocking should preclude any big amplification of any of the waves but at least we'll have some shots of warm advection snows as they roll east.

[dryslot]

Who's up for a few days in Aroostook County? Hotels..some pretty nice...and not expensive and among the few laces in the lower 48 getting winter.

I am suppose to be up there riding around the 26th if things play out right.

[OKpowdah]

Yes, that is a very good sign.

I think the -PNA pattern is going to be important for us to get some storminess. But as modeled the southern stream appears nearly dormant. May allow for some interesting redeveloping clippers but in general I think it's a relatively dry pattern.

Yeah, and what I was saying is I think that's due to the rise in the EPO domain. We don't have that split flow in the west to deliver disturbances to the southern stream

[dryslot]

Tolland FTL

Mt. Socks FTW

You are going to upset the WOTY with those remarks

[ORH_wxman]

Northern stream action is usually modeled pretty poorly out in the long range. We won't really know if anything comes from them...sometimes when it looks totally boring, we get a northern stream wave look better in the short range.

[CT Rain]

Northern stream action is usually modeled pretty poorly out in the long range. We won't really know if anything comes from them...sometimes when it looks totally boring, we get a northern stream wave look better in the short range.

I think we're going to have to rely on the northern stream for fun in the D10-D15 range but it will be hard to pin down specifics as you said.

[weathafella]

Disturbances running (hopefully) under us creating several inches every few days works for me. It worked 18 winters ago with a couple f embedded over performers.

[wxsniss]

Disturbances running (hopefully) under us creating several inches every few days works for me. It worked 18 winters ago with a couple f embedded over performers.

My first winter in Boston... set a very high standard, followed soon after by the epic 95-96... man were we spoiled!

What a difference a 12Z suite makes... strongest evidence yet that the AO is gonna take a hit... increasingly appears that the top of the order is up Jan 20-31 to challenge this shutout, and I'm still not clear on what pattern takes hold thereafter. We'll see!

[CT Rain]

The interesting question down the line is how much impact the stratospheric warming will have up in the Arctic.

Will we see a sustained -AO?

We're already seeing the PV disrupted thanks to that big ridge north of the Caspian Sea and then the monster Bering Strait block that develops next week finished it off. But beyond D10 does the warming downwell to the tropopause...

I have a feeling if we are able to get the AO to dip that may save us from a relatively unfavorable Pacific and renewed ugly Indonesian MJO convection by 2/1.

[CT Rain]

00z GFS has no phase or interaction between southern stream feature and northern stream jet for Thursday storm.

[ORH_wxman]

Well the 00z GFS does give us a snow event next fri night into Sat morning.

[CT Rain]

Well the 00z GFS does give us a snow event next fri night into Sat morning.

yup... that should get the weenies excited

[dryslot]

yup... that should get the weenies excited

Why does anyone even look at the gfs? sound familiar...lol

[ORH_wxman]

yup... that should get the weenies excited

Does it in a totally different manner than the Euro...but both have shown potential for something in that same time frame. At least its something to keep one eye on until it inevitably turns into flurries or just some high clouds by the time we get inside 4 days.

[weatherMA]

Well the 00z GFS does give us a snow event next fri night into Sat morning.

Well the euro had it too so time to lock it. lol only 24 more runs.

[NorEastermass128]

Well the 00z GFS does give us a snow event next fri night into Sat morning.

Is it believable? I know its D6, but could the setup support it?