January Forecast Discussion

[bluewave]

Hopefully people have enjoyed this mild break because we could see temperatures just as cold as we've seen in early January. Any snow cover would certainly enhance the cold out here, maybe below zero temperatures are still in play?

 

The odd thing about this January is the temperature distribution across the whole month. Cold for the first ten days...mild 

for middle ten...cold for the last ten. I am not sure that we have had such a perfect bookend cold with warm in the middle

before. Maybe Uncle has some stats somewhere to see how unusual this pattern is.

1  33  24  29  -4  36   0 0.00  0.0    0  5.6 14 280   M    M   2        23 300 2  33  18  26  -7  39   0 0.33  3.1    0 12.2 21  50   M    M  10 18     28  50 3  18   9  14 -19  51   0 0.29  3.3    6 10.4 21 360   M    M   5 1      29 310 4  29   8  19 -14  46   0 0.00  0.0    6  4.8  9 260   M    M   0        20 240 5  40  27  34   1  31   0 0.14    T    4  3.7  7  70   M    M   7 128    17 240 6  55  19  37   4  28   0 0.36  0.0    1  8.5 18 290   M    M   9 12     29 300 7  19   4  12 -21  53   0 0.00  0.0    0 13.1 23 280   M    M   0        38 270 8  22   9  16 -17  49   0 0.00  0.0    0  7.1 15 290   M    M   2        23 290 9  32  22  27  -5  38   0 0.00  0.0    0  2.9 12 350   M    M   1        16 32010  37  30  34   2  31   0 0.11    T    0  3.4  8  50   M    M   9 18     11 16011  58  37  48  16  17   0 0.50  0.0    0  7.1 17 180   M    M  10 1      28 17012  54  38  46  14  19   0 0.05  0.0    0  8.2 20 290   M    M   6 1      31 29013  51  37  44  12  21   0 0.00  0.0    0  5.2 14 180   M    M   0        24 17014  52  44  48  16  17   0 0.38  0.0    0  5.0 13 230   M    M 

[SnoSki14]

And the negative departures are going to be nearly erased by the weekend after today's plus 10-15 and Thursday and Friday's +5-+10 before it gets colder again. 

 

Kind of like when last month's warmth killed those negative departures although this time we're going to be seeing more cold so the month should definitely wind up negative. 

[Saturn510]

I do think one of these storms will produce but which one is the question. The euro is very consistent during the days 4.5-7 but keeps losing its storms around 100 hours or so.

[PB GFI]

Probably a little overdone  But Jan 22 starts the  2 to 3 weeks of cold .

[PB GFI]

Too bad that's not D3 but D7 .

[MJO812]

Euro ensembles have a storm signal on the 22 snd 25.

[bluewave]

Probably a little overdone  But Jan 22 starts the  2 to 3 weeks of cold .

 

It would be nice if they could dial down the cold bias with a good snowpack in place like right after the

snow at the beginning of the month. But it did better with the cold several days later after most of the

snowpack melted.

 

[Rjay]

Too bad that's not D3 but D7 .

Yea and you can see it bomb on the next frame as it passes near or over the BM

[PB GFI]

Yea and you can see it bomb on the next frame as it passes near or over the BM

Yeh that's a Blizzard for New England in the next frame .

The plus for this system is its been on the Euro and GFS for a week now .

 

But the Euro gave me the shakes yesterday , at 0z it took a Blizzard into SNE this weekend and then at 12z it was a total miss.

So I will be more comfortable if it  shows up inside 84 hrs  

[PB GFI]

It would be nice if they could dial down the cold bias with a good snowpack in place like right after the

snow at the beginning of the month. But it did better with the cold several days later after most of the

snowpack melted.

 

Screen shot 2014-01-15 at 3.33.22 PM.png

I think this comes in waves  .Its not   1 and done and once its cold , it just reloads through D 15

 

HM and DSNOW s 28th system is there as well .

[Superstorm93]

 

 

.LONG TERM /FRIDAY THROUGH TUESDAY/...

A DEEP H5 LOW OVER THE ARCTIC CIRCLE WILL DRIFT SEWD TOWARDS HUDSON

BAY...BRINGING A RETURN TO WINTER ACROSS THE TRI-STATE REGION.

RAPID SUCCESSION OF H5 TROF PASSAGES CONTINUES LATE FRI INTO SAT.

MOISTURE TRANSPORT IS MINIMAL AT BEST...AND COMPLICATING THE FORCING

IS WEAK SUBSIDENCE IN THE WAKE OF THE DOWNSTREAM SYSTEM. AS A

RESULT...AREAS OF UNORGANIZED MAINLY LIGHT PCPN ARE EXPECTED LATE

FRI INTO THE FIRST PART OF SAT. A DUSTING/COATING OF SNOW POSSIBLE

LATE FRI NGT INTO SAT MRNG. OTHERWISE...RAIN LIKELY TO MIX IN AT THE

COASTS AT LEAST DURING THE DAY ON FRI...WITH THE WARMER BL

PRECLUDING ANY ACCUMS ACROSS THE INTERIOR DURING THIS SAME PERIOD.

THE AIRMASS COOLS FURTHER BEHIND THIS SYSTEM FOR THE WEEKEND. THE

GFS BRINGS A CLIPPER THRU SUN. THIS WOULD BE CAPABLE OF PUTTING DOWN

SOME MORE LIGHT SNOW. THE ECMWF IS FURTHER S...THEREBY SUPPRESSING

THE PCPN AXIS AND KEEPING THE CWA DRY. AS A RESULT...WILL FCST CHC

POPS FOR THE SYSTEM ATTM. REGARDLESS OF THE AMOUNT OF PCPN...WINDS

WILL RAMP UP BEHIND THE LOW AND AN EVEN COLDER AIRMASS WILL SETTLE

IN.

THE NEXT SYSTEM IS LATE TUE-WED...WITH THE PATTERN CONDUCIVE TO THE

DEVELOPMENT OF LOW PRES OFF THE ATLANTIC SEABOARD. BOTH THE GFS AND

ECMWF ARE KEYING IN ON SOME DEVELOPMENT...IT WILL JUST BE A MATTER

OF EXACTLY WHERE. HAVE INCLUDED LOW CHC POPS FOR SNOW...AS THE

AIRMASS BUILDING IN WITH THIS SYSTEM SHOULD BE ARCTIC IN NATURE

RELEGATING ANY MIXING TO THE OCEANFRONT.

&&

[bluewave]

I think this comes in waves  .Its not   1 and done and once its cold , it just reloads through D 15

 

HM and DSNOW s 28th system is there as well .

 

You can see the second Arctic shot as the as the ridge peaks near Alaska D 10-15.

 

[EasternLI]

I'm pretty stoked, love miller B patterns, they can be exciting. That deal on the 22-23 looks like it might have legs. 

[Metsfan]

Check out my blog on the potential cold and snow for the second half of January at liveweatherblogs.com. As always thanks.

[PB GFI]

Where`s that cold air gona go  ?

[Monmouth_County_Jacpot]

I think this cold shot has some staying power anyone agree??

[Metsfan]

I think this cold shot has some staying power anyone agree??

 That image shows the -epo connecting with the -nao and develops cross polar flow. If that's the case then we can lock in the cold for a while.

[earthlight]

The big mistake being made with posting those maps is that they are the Euro Ensemble Control run, not the Ensemble mean.

[PB GFI]

The big mistake being made with posting those maps is that they are the Euro Ensemble Control run, not the Ensemble mean.

Its the OP run 51 times , the ensembles get muted , I know the difference

I  use the ensembles first , but when the Control shows extremes it sometimes sniffs stuff out IMO and experience

[EasternLI]

Check out my blog on the potential cold and snow for the second half of January at liveweatherblogs.com. As always thanks.

 

Nice write-up

[REDMK6GLI]

 That image shows the -epo connecting with the -nao and develops cross polar flow. If that's the case then we can lock in the cold for a while.

 

VERY good read and it gives a good amount of hope for us wishing for another nice snowstorm before winter closes the curtains this season

[Metsfan]

Nice write-up

Much appreciated.  

[earthlight]

Just a note, the post below includes Euro ensemble images that will be removed in a few hours due to restrictions. So if you're looking for the graphics at a later time, use your personal source for them.

 

The progression of the pattern on the Euro ensembles from the 12z run this afternoon (12z/15 for future reference) was one of the more exciting I have seen modeled in the past few years in terms of signaling the eventual delivery of cold and multiple chances for snowstorms of moderate to significant nature. Exactly how the pattern plays out remains a mystery at this juncture, especially as we continue to overanalyze and interpret operational model guidance -- which is never smart. The individual nuances of the pattern are going to take days to iron out, but as we move forward I am confident that we will start to see favorable results emerge. Although I have been screaming about this potential for a weeks time now, in the below post I will do my best to illustrate why I have been doing so -- and why the pattern progression will bring potential but also require patience.

 

The first development of note is that the ECMWF has finally caved to the GFS and GEFS interpretation of tropical forcing which will increase later this week and help the development of some major pattern changes. The ECMWF had previously been very stubborn in insisting against this development and keeping the impulse quite week. This cave is very important for the eventual changes in the Pacific.

 

 

All forecast models are in very good agreement in the eventual development of a PNA ridge on the west coast -- a beast of one, really -- which will eventually push northward into British Columbia. In addition, a North Atlantic ridge is forecast to develop while the EPO dips down and eventually falls tremendously negative with the ridge building into the North Pacific. We can see in the below imagery that the EPO is forecast to fall tremendously by Days 5-7 and while there is some uncertainty amongst ensembles, all agree on a below -2 value and some are very literally off the charts with values well below - 5. As Don S noted a few days ago, the last three cases of this type of EPO drop in January were 1994, 2003 and 2010. All three of those cases should bring back memories.

 

 

That being said, the pattern over the next few days will remain largely progressive prior to the development of these changes. A quick glance at all forecast operational and ensemble guidance shows several storm systems amidst an active flow of mid level distubrances, developing well to the east/northeast of our area. This is not surprising due to the gyre near the Great Lakes -- and although the storms are developing well to our northeast we may still be able to squeeze out some snow at times which should come as a bonus to all of us.

 

This gyre eventually shifts north and east on all forecast models and becomes a centerpiece of the Polar Vortex over Eastern Canada. This becomes extremely important by Days 5-7 as its positioning will have a major say in the eventual track of forthcoming disturbances from the Pacific. The new trend on all guidance today is to elongate this vortex in a more west to east direction. Below, the ECMWF Ensemble mean (yes, this is a mean forecast) shows the setup on January 20th very well -- with presumably decent agreement given the mean anomalies. There is a tremendous ridge in a favorable position on the West Coast, an elongated Polar Vortex over Southeast Canada, and importantly -- some ridging and above normal height anomalies poking into Greenland and the Davis Straight (where have we seen that before, how about two weeks ago).

 

 

The elongation of this polar vortex is essential -- and it starts with the piece of the PV which phases over New England this weekend. This elongated position allows the Polar Vortex to interact with any disturbance that drops into the trough over the MS Valley from the Pacific. This is a huge change on the forecast models from yesterday which were showing this PV staying as a huge rotating gyre of cold air.

 

The guidance is beginning to show this potential as the elongated PV is now dropping in and phasing with the mid level disturbance over the MS Valley on Jan 22 or whereabouts, producing a potential event. This event may very well turn out to produce for our area -- but it is the first in a line of several and the setup is still a bit too far east.

 

 

But do not fret, because by this time (Day 7) the pattern is in retrogression mode on all forecast models and ensembles. So the PNA ridge is pushing westward and the gyre over the Northeast is now forecast to phase in and then tug back to the north. The raging -EPO and +PNA pattern at this time open the door for this gyre to retrograde westward into Central Canada, while some additional ridging builds north of it in the higher latitudes. This brings the trough axis farther west towards the Mississippi River. Any disturbance that comes over the top of the Pacific Ridge at this time will amplify in a nearly ideal and classic spot for snowstorms in the Northeast US.

 

 

It is this point which I am trying to drive home in the upcoming pattern -- this is not a one and done scenario. Although initially progressive, the anomalous nature and retrogressive developments in the pattern suggest not just one chance, but multiple chances for significant winter weather events in the Northeast United States.

 

That being said, nothing is set in stone. As we have all learned the hard way over the past several years, forecast models at this range can be wildly incorrect with their pattern evolutions. But this time, seeing tremendous ensemble support and having the backing of tropical forcing and changes which can be traced all the way up to the stratosphere -- leads to enhanced confidence that we are about 5-7 days away from entering a very exciting time period.

 

Strap in boys.

[96blizz]

Just a note, the post below includes Euro ensemble images that will be removed in a few hours due to restrictions. So if you're looking for the graphics at a later time, use your personal source for them.

The progression of the pattern on the Euro ensembles from the 12z run this afternoon (12z/15 for future reference) was one of the more exciting I have seen modeled in the past few years in terms of signaling the eventual delivery of cold and multiple chances for snowstorms of moderate to significant nature. Exactly how the pattern plays out remains a mystery at this juncture, especially as we continue to overanalyze and interpret operational model guidance -- which is never smart. The individual nuances of the pattern are going to take days to iron out, but as we move forward I am confident that we will start to see favorable results emerge. Although I have been screaming about this potential for a weeks time now, in the below post I will do my best to illustrate why I have been doing so -- and why the pattern progression will bring potential but also require patience.

The first development of note is that the ECMWF has finally caved to the GFS and GEFS interpretation of tropical forcing which will increase later this week and help the development of some major pattern changes. The ECMWF had previously been very stubborn in insisting against this development and keeping the impulse quite week. This cave is very important for the eventual changes in the Pacific.

ECMF_phase_51m_full.gif

All forecast models are in very good agreement in the eventual development of a PNA ridge on the west coast -- a beast of one, really -- which will eventually push northward into British Columbia. In addition, a North Atlantic ridge is forecast to develop while the EPO dips down and eventually falls tremendously negative with the ridge building into the North Pacific. We can see in the below imagery that the EPO is forecast to fall tremendously by Days 5-7 and while there is some uncertainty amongst ensembles, all agree on a below -2 value and some are very literally off the charts with values well below - 5. As Don S noted a few days ago, the last three cases of this type of EPO drop in January were 1994, 2003 and 2010. All three of those cases should bring back memories.

That being said, the pattern over the next few days will remain largely progressive prior to the development of these changes. A quick glance at all forecast operational and ensemble guidance shows several storm systems amidst an active flow of mid level distubrances, developing well to the east/northeast of our area. This is not surprising due to the gyre near the Great Lakes -- and although the storms are developing well to our northeast we may still be able to squeeze out some snow at times which should come as a bonus to all of us.

This gyre eventually shifts north and east on all forecast models and becomes a centerpiece of the Polar Vortex over Eastern Canada. This becomes extremely important by Days 5-7 as its positioning will have a major say in the eventual track of forthcoming disturbances from the Pacific. The new trend on all guidance today is to elongate this vortex in a more west to east direction. Below, the ECMWF Ensemble mean (yes, this is a mean forecast) shows the setup on January 20th very well -- with presumably decent agreement given the mean anomalies. There is a tremendous ridge in a favorable position on the West Coast, an elongated Polar Vortex over Southeast Canada, and importantly -- some ridging and above normal height anomalies poking into Greenland and the Davis Straight (where have we seen that before, how about two weeks ago).

euro1.png

The elongation of this polar vortex is essential -- and it starts with the piece of the PV which phases over New England this weekend. This elongated position allows the Polar Vortex to interact with any disturbance that drops into the trough over the MS Valley from the Pacific. This is a huge change on the forecast models from yesterday which were showing this PV staying as a huge rotating gyre of cold air.

The guidance is beginning to show this potential as the elongated PV is now dropping in and phasing with the mid level disturbance over the MS Valley on Jan 22 or whereabouts, producing a potential event. This event may very well turn out to produce for our area -- but it is the first in a line of several and the setup is still a bit too far east.

euro2.png

But do not fret, because by this time (Day 7) the pattern is in retrogression mode on all forecast models and ensembles. So the PNA ridge is pushing westward and the gyre over the Northeast is now forecast to phase in and then tug back to the north. The raging -EPO and +PNA pattern at this time open the door for this gyre to retrograde westward into Central Canada, while some additional ridging builds north of it in the higher latitudes. This brings the trough axis farther west towards the Mississippi River. Any disturbance that comes over the top of the Pacific Ridge at this time will amplify in a nearly ideal and classic spot for snowstorms in the Northeast US.

euro3.png

It is this point which I am trying to drive home in the upcoming pattern -- this is not a one and done scenario. Although initially progressive, the anomalous nature and retrogressive developments in the pattern suggest not just one chance, but multiple chances for significant winter weather events in the Northeast United States.

That being said, nothing is set in stone. As we have all learned the hard way over the past several years, forecast models at this range can be wildly incorrect with their pattern evolutions. But this time, seeing tremendous ensemble support and having the backing of tropical forcing and changes which can be traced all the way up to the stratosphere -- leads to enhanced confidence that we are about 5-7 days away from entering a very exciting time period.

Strap in boys.

Just phenomenal. Impressive is not a strong enough word...

[PB GFI]

Great piece John . Think by Monday we will have multiple threats being followed inside 7 days.

[REDMK6GLI]

Just a note, the post below includes Euro ensemble images that will be removed in a few hours due to restrictions. So if you're looking for the graphics at a later time, use your personal source for them.

 

The progression of the pattern on the Euro ensembles from the 12z run this afternoon (12z/15 for future reference) was one of the more exciting I have seen modeled in the past few years in terms of signaling the eventual delivery of cold and multiple chances for snowstorms of moderate to significant nature. Exactly how the pattern plays out remains a mystery at this juncture, especially as we continue to overanalyze and interpret operational model guidance -- which is never smart. The individual nuances of the pattern are going to take days to iron out, but as we move forward I am confident that we will start to see favorable results emerge. Although I have been screaming about this potential for a weeks time now, in the below post I will do my best to illustrate why I have been doing so -- and why the pattern progression will bring potential but also require patience.

 

The first development of note is that the ECMWF has finally caved to the GFS and GEFS interpretation of tropical forcing which will increase later this week and help the development of some major pattern changes. The ECMWF had previously been very stubborn in insisting against this development and keeping the impulse quite week. This cave is very important for the eventual changes in the Pacific.

 

ECMF_phase_51m_full.gif

 

All forecast models are in very good agreement in the eventual development of a PNA ridge on the west coast -- a beast of one, really -- which will eventually push northward into British Columbia. In addition, a North Atlantic ridge is forecast to develop while the EPO dips down and eventually falls tremendously negative with the ridge building into the North Pacific. We can see in the below imagery that the EPO is forecast to fall tremendously by Days 5-7 and while there is some uncertainty amongst ensembles, all agree on a below -2 value and some are very literally off the charts with values well below - 5. As Don S noted a few days ago, the last three cases of this type of EPO drop in January were 1994, 2003 and 2010. All three of those cases should bring back memories.

 

gefs_epo_06.png

 

That being said, the pattern over the next few days will remain largely progressive prior to the development of these changes. A quick glance at all forecast operational and ensemble guidance shows several storm systems amidst an active flow of mid level distubrances, developing well to the east/northeast of our area. This is not surprising due to the gyre near the Great Lakes -- and although the storms are developing well to our northeast we may still be able to squeeze out some snow at times which should come as a bonus to all of us.

 

This gyre eventually shifts north and east on all forecast models and becomes a centerpiece of the Polar Vortex over Eastern Canada. This becomes extremely important by Days 5-7 as its positioning will have a major say in the eventual track of forthcoming disturbances from the Pacific. The new trend on all guidance today is to elongate this vortex in a more west to east direction. Below, the ECMWF Ensemble mean (yes, this is a mean forecast) shows the setup on January 20th very well -- with presumably decent agreement given the mean anomalies. There is a tremendous ridge in a favorable position on the West Coast, an elongated Polar Vortex over Southeast Canada, and importantly -- some ridging and above normal height anomalies poking into Greenland and the Davis Straight (where have we seen that before, how about two weeks ago).

 

euro1.png

 

The elongation of this polar vortex is essential -- and it starts with the piece of the PV which phases over New England this weekend. This elongated position allows the Polar Vortex to interact with any disturbance that drops into the trough over the MS Valley from the Pacific. This is a huge change on the forecast models from yesterday which were showing this PV staying as a huge rotating gyre of cold air.

 

The guidance is beginning to show this potential as the elongated PV is now dropping in and phasing with the mid level disturbance over the MS Valley on Jan 22 or whereabouts, producing a potential event. This event may very well turn out to produce for our area -- but it is the first in a line of several and the setup is still a bit too far east.

 

euro2.png

 

But do not fret, because by this time (Day 7) the pattern is in retrogression mode on all forecast models and ensembles. So the PNA ridge is pushing westward and the gyre over the Northeast is now forecast to phase in and then tug back to the north. The raging -EPO and +PNA pattern at this time open the door for this gyre to retrograde westward into Central Canada, while some additional ridging builds north of it in the higher latitudes. This brings the trough axis farther west towards the Mississippi River. Any disturbance that comes over the top of the Pacific Ridge at this time will amplify in a nearly ideal and classic spot for snowstorms in the Northeast US.

 

euro3.png

 

It is this point which I am trying to drive home in the upcoming pattern -- this is not a one and done scenario. Although initially progressive, the anomalous nature and retrogressive developments in the pattern suggest not just one chance, but multiple chances for significant winter weather events in the Northeast United States.

 

That being said, nothing is set in stone. As we have all learned the hard way over the past several years, forecast models at this range can be wildly incorrect with their pattern evolutions. But this time, seeing tremendous ensemble support and having the backing of tropical forcing and changes which can be traced all the way up to the stratosphere -- leads to enhanced confidence that we are about 5-7 days away from entering a very exciting time period.

 

Strap in boys.

 

never seizes to amaze me with the reach of intelligence in forecasting john, great read and VERY imformative in all aspects  

[SnoSki14]

Superb explanation on this upcoming pattern, with details about every variable out there. The pattern looks very exciting next week and fingers crossed for multiple snow events, and the fact that it sticks around for a long time is a huge plus. 

 

Crazy fog right now by the way. 

[Johnno]

not a piece of clothing left on, very nice write up

[CoastalWx]

Nice stuff John. I noticed that PV drop to for next week.

[earthlight]

Appreciate all of the comments. Looking forward to the next few weeks.

Nice stuff John. I noticed that PV drop to for next week.

Yeah it has changed pretty markedly on all models over the last few days. Once you start retro grading the flow and dropping the PV in like that..we're talking big things.We will see!