Re: Long Range Thread 9.0

[Snow88]

Models are going to struggle to see which shortwave to focus on

[NjWeatherGuy]

Holy Crap....


http://mag.ncep.noaa.gov/Image.php?fhr=225&image=data%2Fgfs%2F06%2Fgfs_namer_225_850_temp_mslp_precip.gif&model=gfs&area=namer¶m=850_temp_mslp_precip&group=Model+Guidance&preselected_formatted_cycle_date=20160109+06+UTC&imageSize=M&ps=model

[NjWeatherGuy]

CMC has a miller B. Rain to snow, more of a NE hit.

[Frank_Wx]

Models are completely lost right now. I'm telling you...these -NAO blocking events always give models problems. The EURO is the best bet and it wants to focus on the very first short wave entering the US this week. If true, we could see a snowstorm Friday instead of Sunday. Heck there are so many short waves we could theoretically see 2-3 snowstorms in a 1 week span.

I'll have a more detailed writeup tomorrow.

[jmanley32]

If the euro played put like last night and a bit closer that would b a historic storm.

[jmanley32]

Models are completely lost right now. I'm telling you...these -NAO blocking events always give models problems. The EURO is the best bet and it wants to focus on the very first short wave entering the US this week. If true, we could see a snowstorm Friday instead of Sunday. Heck there are so many short waves we could theoretically see 2-3 snowstorms in a 1 week span.

I'll have a more detailed writeup tomorrow.

frank always making us wait for his insight lol. Frank is there anyway that there actually could b temp issues for coast or is the cold pretty much a given?

[Frank_Wx]

Models are completely lost right now. I'm telling you...these -NAO blocking events always give models problems. The EURO is the best bet and it wants to focus on the very first short wave entering the US this week. If true, we could see a snowstorm Friday instead of Sunday. Heck there are so many short waves we could theoretically see 2-3 snowstorms in a 1 week span.

I'll have a more detailed writeup tomorrow.

frank always making us wait for his insight lol. Frank is there anyway that there actually could b temp issues for coast or is the cold pretty much a given?

There could be temp issues if there is a 2nd or 3rd storm because the cold has to reload. For the first system, I think we should be ok. But hard to tell right now.

[snow247]

6z GFS is an all out inland snowstorm.

Way to early to know where it will snow at this point

Clearly, I'm just posting what the run showed.

[Frank_Wx]

We're seeing signs the Strat PV could finally get displaced by the end of January. This is great news because once the tropical forcing event ends, we'll need another mechanism to bring back the Atlantic blocking. Hopefully this holds on future model runs.

[skinsfan1177]

Wouldn't these powerful storms draw in the cold especially being a cold source to the north. Also didn't mugs show really cold air is coming

[amugs]

Grwat post from Earthlight:
Over the past week or so, forecast models have come into much better agreement on the eventual evolution of major global circulations. A large scale hemispheric pattern change, driven by tropospheric forces and changes, is underway and already in motion. The atmosphere is very busy right now -- and changing at a dramatic pace. Much of what was discussed earlier in this thread can be thanked for driving these changes in the pattern. A stratospheric disruption (not a SSW, but a significant two wave event) plus a highly anomalous ridge in the Kara Sea, helped to force a wave break pattern that has totally disrupted the flow of the atmosphere. Things will continue to accelerate from here.

Forecast models are coming into agreement on tremendous, and potentially historic, high latitude blocking during the middle of January. In fact, GFS and ECMWF forecasts for ridge heights at 500mb in the Davis Straight are above the 90th percentile for DJF in recorded history -- and approaching the all time record. The height field projected by the GFS over the past 24 hours over the Davis Straight and Greenland would exceed that of 2009-2010 in strength.

gfswow.thumb.PNG.b7f0f5b7f38d4e9cceecb78

The way the pattern change plays out is of critical importance. Tropical forcing and convection aligning near the dateline has forced a retrograding upper level low to move toward the Aleutian Islands. This trough base and orientation allows for a tremendous ridge to be pumped up to the east over the West Coast of the United States into British Columbia. The wave break pattern on the other side of the globe -- Kara Sea Ridge -- forces a large ridge to build into the EPO and AO regions. Meanwhile, the tropospheric changes occurring dislodge the PV to the south toward Hudson's Bay.

As this occurs, ridging is increased to the north of the Polar Vortex -- into Greenland. This ridging is forecast to become extremely anomalous over the next 7 days. With a closed 552dm 500mb height ridge over Greenland, the Davis Straight, and the Arctic Circle, a significant supply of cold air is expected to be dislodged into Canada and the Northern 1/3 of the United States. High latitude blocking is forecast to reach extreme and/or historic levels across the entire Arctic from Greenland to the Arctic Circle and EPO regions.

Forecast models indicate the Arctic Oscillation could approach an incredible -7 -- which is almost unheard of. The statistics supporting Arctic Oscillation values below -5.5 in January are ridiculous for both snow and cold not only now, but through February. In addition, if the AO does fall near -5, this will be the most prolific flip from positive to negative in DJF recorded history for the Arctic Oscillation. The blocking we are seeing modeled is major league.

gfsaowow.thumb.png.32281a6f9609e584492c3

While this is occurring, the subtropical jet -- aided and signaled by ridiculous atmospheric angular momentum -- will support the development of a split flow on the West Coast of the United States. A significant number of disturbances are likely to fall underneath a more steady Western USA ridge axis. These storm systems will be energetic and Pacific/STJ influenced with an anomalous amount of moisture and energy.

With all of this being said: I believe we are going to enter a period of potentially memorable winter weather over the next 2 to 3 weeks. This period should include one or more opportunities for significant snowfall.

At the current moment, individual storm threats appear extremely muted on forecast models. However, the general setup through the Day 10 period appears highly conducive for East Coast snowfall. There are several features that are on the table which we typically look for in a snowstorm threat. A large, anomalous block is helping to dislodge the Polar Vortex to the south. Prior disturbances are likely to wrap up in the 50/50 position, or nearby, for a period of time. This block is also helping to slow the downstream flow to support amplification. A ridge on the West Coast is helping to dislodge arctic air and energy from the EPO region into the Northern 1/3 in the United States. An active subtropical jet will provide multiple disturbances underneath a split flow.

We are playing with the big boys with this pattern -- and the potential exists for significant and major storm systems. These patterns are classic for producing some of the more powerful and impactful storms systems we have noted in the Eastern United States. But there are many individual features that need to be ironed out over time as we approach any potential event.

gfseuroblock.thumb.gif.d27b0a1a4519f09c5

Exactly how these features behave will be paramount. Working in our favor will be the strength and positioning of the high latitude blocking, which shfits westward over the top of Greenland toward the Davis Straight. Wave spacing and compression allows the Polar Vortex to be elongated and stretched, while maintaining its intensity. An elongated PV not only provides cold air and confluence, but offers potential for a full latitude trough and polar phase. This is critical for positioning of a potential 50/50 low -- which we do not need, but would be extremely helpful to our winter weather chances.

Individual nuances such as shortwave strength and energy, amplitude and movement of aforementioned features, and synoptic differences, will play a huge role moving forward. The general signal as it stands currently suggests the potential for a Major Winter Storm in the Northeast from January 17th through 20th. This storm has the potential to produce significant snowfall in our area. That being said, it is not a guarantee that this storm produces.

The general idea with these patterns is that it is a matter of when, not if. At least one disturbance is very likely to produce for our area. As long as the forecast model guidance in the medium range is not wildly incorrect, this is a classic "Powder Keg" pattern.

So here is my suggestion over the next few days: Enjoy it. Remember that nothing is guaranteed and keep expectations low. We all know how these things work -- it is entirely possible that despite the pattern being perfect, we walk out of here with very little to show for it. However, understand that the potential is much higher than normal for significant snowfall in this pattern -- and that it could be a very fun, wild, memorable ride.

[Frank_Wx]

Look at how many pieces of upper energy the 12z GFS is showing. It has no clue which one to focus on. There is also no western ridge.

[skinsfan1177]

Grwat post from Earthlight:
Over the past week or so, forecast models have come into much better agreement on the eventual evolution of major global circulations. A large scale hemispheric pattern change, driven by tropospheric forces and changes, is underway and already in motion. The atmosphere is very busy right now -- and changing at a dramatic pace. Much of what was discussed earlier in this thread can be thanked for driving these changes in the pattern. A stratospheric disruption (not a SSW, but a significant two wave event) plus a highly anomalous ridge in the Kara Sea, helped to force a wave break pattern that has totally disrupted the flow of the atmosphere. Things will continue to accelerate from here.

Forecast models are coming into agreement on tremendous, and potentially historic,  high latitude blocking during the middle of January. In fact, GFS and ECMWF forecasts for ridge heights at 500mb in the Davis Straight are above the 90th percentile for DJF in recorded history -- and approaching the all time record. The height field projected by the GFS over the past 24 hours over the Davis Straight and Greenland would exceed that of 2009-2010 in strength.

gfswow.thumb.PNG.b7f0f5b7f38d4e9cceecb78

The way the pattern change plays out is of critical importance. Tropical forcing and convection aligning near the dateline has forced a retrograding upper level low to move toward the Aleutian Islands. This trough base and orientation allows for a tremendous ridge to be pumped up to the east over the West Coast of the United States into British Columbia. The wave break pattern on the other side of the globe -- Kara Sea Ridge -- forces a large ridge to build into the EPO and AO regions. Meanwhile, the tropospheric changes occurring dislodge the PV to the south toward Hudson's Bay.

As this occurs, ridging is increased to the north of the Polar Vortex -- into Greenland. This ridging is forecast to become extremely anomalous over the next 7 days. With a closed 552dm 500mb height ridge over Greenland, the Davis Straight, and the Arctic Circle, a significant supply of cold air is expected to be dislodged into Canada and the Northern 1/3 of the United States. High latitude blocking is forecast to reach extreme and/or historic levels across the entire Arctic from Greenland to the Arctic Circle and EPO regions.

Forecast models indicate the Arctic Oscillation could approach an incredible -7 -- which is almost unheard of. The statistics supporting Arctic Oscillation values below -5.5 in January are ridiculous for both snow and cold not only now, but through February. In addition, if the AO does fall near -5, this will be the most prolific flip from positive to negative in DJF recorded history for the Arctic Oscillation. The blocking we are seeing modeled is major league.

gfsaowow.thumb.png.32281a6f9609e584492c3

While this is occurring, the subtropical jet -- aided and signaled by ridiculous atmospheric angular momentum -- will support the development of a split flow on the West Coast of the United States. A significant number of disturbances are likely to fall underneath a more steady Western USA ridge axis. These storm systems will be energetic and Pacific/STJ influenced with an anomalous amount of moisture and energy.

With all of this being said: I believe we are going to enter a period of potentially memorable winter weather over the next 2 to 3 weeks. This period should include one or more opportunities for significant snowfall.

At the current moment, individual storm threats appear extremely muted on forecast models. However, the general setup through the Day 10 period appears highly conducive for East Coast snowfall. There are several features that are on the table which we typically look for in a snowstorm threat. A large, anomalous block is helping to dislodge the Polar Vortex to the south. Prior disturbances are likely to wrap up in the 50/50 position, or nearby, for a period of time. This block is also helping to slow the downstream flow to support amplification. A ridge on the West Coast is helping to dislodge arctic air and energy from the EPO region into the Northern 1/3 in the United States. An active subtropical jet will provide multiple disturbances underneath a split flow.

We are playing with the big boys with this pattern -- and the potential exists for significant and major storm systems. These patterns are classic for producing some of the more powerful and impactful storms systems we have noted in the Eastern United States. But there are many individual features that need to be ironed out over time as we approach any potential event.

gfseuroblock.thumb.gif.d27b0a1a4519f09c5

Exactly how these features behave will be paramount. Working in our favor will be the strength and positioning of the high latitude blocking, which shfits westward over the top of Greenland toward the Davis Straight. Wave spacing and compression allows the Polar Vortex to be elongated and stretched, while maintaining its intensity. An elongated PV not only provides cold air and confluence, but offers potential for a full latitude trough and polar phase. This is critical for positioning of a potential 50/50 low -- which we do not need, but would be extremely helpful to our winter weather chances.

Individual nuances such as shortwave strength and energy, amplitude and movement of aforementioned features, and synoptic differences, will play a huge role moving forward. The general signal as it stands currently suggests the potential for a Major Winter Storm in the Northeast from January 17th through 20th. This storm has the potential to produce significant snowfall in our area. That being said, it is not a guarantee that this storm produces.

The general idea with these patterns is that it is a matter of when, not if. At least one disturbance is very likely to produce for our area. As long as the forecast model guidance in the medium range is not wildly incorrect, this is a classic "Powder Keg" pattern.

So here is my suggestion over the next few days: Enjoy it. Remember that nothing is guaranteed and keep expectations low. We all know how these things work -- it is entirely possible that despite the pattern being perfect, we walk out of here with very little to show for it.  However, understand that the potential is much higher than normal for significant snowfall in this pattern -- and that it could be a very fun, wild, memorable ride.

What a great read mugs lots of info. Where do you get earthlight and isotherm info from?

[NjWeatherGuy]

GFS has an overrunning event, CMC has a large coastal.

http://meteocentre.com/models/explorateur.php?lang=en&map=na&run=12&mod=gemglb&stn=PNMPR&comp=1&run2=12&mod2=gemglb&stn2=PNMPR&hh2=204&fixhh=1&stn2_type=prog&mode=latest&yyyy=latest&mm=latest&dd=latest&hh=216

[oldtimer]

Thanks. Mugs. Enjoyed reading that piece. So interesting I'm encouraged that we will get a good dose of white gold before its all said and done

[weatherwatchermom]

Grwat post from Earthlight:
Over the past week or so, forecast models have come into much better agreement on the eventual evolution of major global circulations. A large scale hemispheric pattern change, driven by tropospheric forces and changes, is underway and already in motion. The atmosphere is very busy right now -- and changing at a dramatic pace. Much of what was discussed earlier in this thread can be thanked for driving these changes in the pattern. A stratospheric disruption (not a SSW, but a significant two wave event) plus a highly anomalous ridge in the Kara Sea, helped to force a wave break pattern that has totally disrupted the flow of the atmosphere. Things will continue to accelerate from here.

Forecast models are coming into agreement on tremendous, and potentially historic,  high latitude blocking during the middle of January. In fact, GFS and ECMWF forecasts for ridge heights at 500mb in the Davis Straight are above the 90th percentile for DJF in recorded history -- and approaching the all time record. The height field projected by the GFS over the past 24 hours over the Davis Straight and Greenland would exceed that of 2009-2010 in strength.

gfswow.thumb.PNG.b7f0f5b7f38d4e9cceecb78

The way the pattern change plays out is of critical importance. Tropical forcing and convection aligning near the dateline has forced a retrograding upper level low to move toward the Aleutian Islands. This trough base and orientation allows for a tremendous ridge to be pumped up to the east over the West Coast of the United States into British Columbia. The wave break pattern on the other side of the globe -- Kara Sea Ridge -- forces a large ridge to build into the EPO and AO regions. Meanwhile, the tropospheric changes occurring dislodge the PV to the south toward Hudson's Bay.

As this occurs, ridging is increased to the north of the Polar Vortex -- into Greenland. This ridging is forecast to become extremely anomalous over the next 7 days. With a closed 552dm 500mb height ridge over Greenland, the Davis Straight, and the Arctic Circle, a significant supply of cold air is expected to be dislodged into Canada and the Northern 1/3 of the United States. High latitude blocking is forecast to reach extreme and/or historic levels across the entire Arctic from Greenland to the Arctic Circle and EPO regions.

Forecast models indicate the Arctic Oscillation could approach an incredible -7 -- which is almost unheard of. The statistics supporting Arctic Oscillation values below -5.5 in January are ridiculous for both snow and cold not only now, but through February. In addition, if the AO does fall near -5, this will be the most prolific flip from positive to negative in DJF recorded history for the Arctic Oscillation. The blocking we are seeing modeled is major league.

gfsaowow.thumb.png.32281a6f9609e584492c3

While this is occurring, the subtropical jet -- aided and signaled by ridiculous atmospheric angular momentum -- will support the development of a split flow on the West Coast of the United States. A significant number of disturbances are likely to fall underneath a more steady Western USA ridge axis. These storm systems will be energetic and Pacific/STJ influenced with an anomalous amount of moisture and energy.

With all of this being said: I believe we are going to enter a period of potentially memorable winter weather over the next 2 to 3 weeks. This period should include one or more opportunities for significant snowfall.

At the current moment, individual storm threats appear extremely muted on forecast models. However, the general setup through the Day 10 period appears highly conducive for East Coast snowfall. There are several features that are on the table which we typically look for in a snowstorm threat. A large, anomalous block is helping to dislodge the Polar Vortex to the south. Prior disturbances are likely to wrap up in the 50/50 position, or nearby, for a period of time. This block is also helping to slow the downstream flow to support amplification. A ridge on the West Coast is helping to dislodge arctic air and energy from the EPO region into the Northern 1/3 in the United States. An active subtropical jet will provide multiple disturbances underneath a split flow.

We are playing with the big boys with this pattern -- and the potential exists for significant and major storm systems. These patterns are classic for producing some of the more powerful and impactful storms systems we have noted in the Eastern United States. But there are many individual features that need to be ironed out over time as we approach any potential event.

gfseuroblock.thumb.gif.d27b0a1a4519f09c5

Exactly how these features behave will be paramount. Working in our favor will be the strength and positioning of the high latitude blocking, which shfits westward over the top of Greenland toward the Davis Straight. Wave spacing and compression allows the Polar Vortex to be elongated and stretched, while maintaining its intensity. An elongated PV not only provides cold air and confluence, but offers potential for a full latitude trough and polar phase. This is critical for positioning of a potential 50/50 low -- which we do not need, but would be extremely helpful to our winter weather chances.

Individual nuances such as shortwave strength and energy, amplitude and movement of aforementioned features, and synoptic differences, will play a huge role moving forward. The general signal as it stands currently suggests the potential for a Major Winter Storm in the Northeast from January 17th through 20th. This storm has the potential to produce significant snowfall in our area. That being said, it is not a guarantee that this storm produces.

The general idea with these patterns is that it is a matter of when, not if. At least one disturbance is very likely to produce for our area. As long as the forecast model guidance in the medium range is not wildly incorrect, this is a classic "Powder Keg" pattern.

So here is my suggestion over the next few days: Enjoy it. Remember that nothing is guaranteed and keep expectations low. We all know how these things work -- it is entirely possible that despite the pattern being perfect, we walk out of here with very little to show for it.  However, understand that the potential is much higher than normal for significant snowfall in this pattern -- and that it could be a very fun, wild, memorable ride.

great read thank you for sharing

[Guest]

This earth light guy besides being bright, sounds really fired up about what's to come

[Frank_Wx]

The 12z GEFS shows an impressive storm signal around the 18th. Here is a look at the 500mb height anomalies. The wesr-based block is really impressive, the 50/50 low is ideally placed, and there's plenty of cold air. Again, the problem is the Pacific. The ridge is muted and there is so much energy entering the country the models are struggling on how to handle them. This is going to be a storm that doesn't show up until we're within 4 days.

[Frank_Wx]

Impressive agreement with GFS Ensemble members

[Guest]

Frank! I know you would like to see more amplification in the Pacific ridge, but it doesn't look bad to me! Has a pretty good dip no?

[Frank_Wx]

200mb CHI Anomalies are centered on 160W later next week. This is from the EURO valid Thursday. This argues for the NPAC trough to be located just south of Alaska.

[Frank_Wx]

Frank!  I know you would like to see more amplification in the Pacific ridge, but it doesn't look bad to me!  Has a pretty good dip no?

The contours show height rise, but if you look at 500mb vort map you'll see all the energy crashing into the west disturbing the ridge from amplifying into western Canada.

[Guest]

Ok

[Frank_Wx]

The 12z euro still has a coastal. Still 200+ hours out. We have a LONG way to go. Enjoy your weekend.

[amugs]

Guys, 3arthlight and isotherm post in the USAwx forum and I pm them on some things as well. Earthlight is very optimistic about the pattern as is Isotherm.
Great to se for the 4th or 5th day we have such a string storm signal on the ensembles. Frank that us great news with the Chi map as I have been fricking harping on since August about............. let's all say it together ready now

TROPICAL FORCING FTW!!

THIS will allow the vortex of death to retrograde sw and allow th epo ti go Neg and pna to rise pos.

Let things play out the next 4 days and after the clipper leaves we have a much better idea.

I say buckle up peeps it is going to be a fun ride!!

[NjWeatherGuy]

EURO = hit, CMC = hit, GEFS = hit, watch out, this is gonna be a long week, soon time for a thread.

[SoulSingMG]

Yep, and the timing looks to be more 18th/19th now, which means I may get home in time for it! Still lots of time to watch but it's been a long long time since models "sorta" converged on a big threat like this.

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