January 2021 General Discussions & Observations Thread

[Allsnow]

 

[LibertyBell]

So that's now three years in a row

[Allsnow]

This would help 

 

 

[Allsnow]

4 hours ago, LibertyBell said:

So that's now three years in a row

We didn’t have one last winter. We got close to it to start December 2019 but then it gained strength and ended our winter 

[SACRUS]

ECM is much colder days 7 - 10 vs prior runs Mon and Tue.  Cold kind of back into the the east.  We'll see if its a trend. 

[donsutherland1]

1 hour ago, Allsnow said:

This would help 

 

 

For the first time, the EPS is now forecasting the zonal mean wind to reverse at 1 mb, 10 mb, and 30 mb. Previously, the reversal was not forecast at 30 mb. If this forecast verifies, this will be a major stratospheric warming event. It will likely have an important impact on the second half of winter, but details as to whether that impact is focused on North America or Eurasia or both remain uncertain.

More than likely, this warming event was the result of the strong blocking that had developed and persisted through much of December. It will likely reinforce the tendency for blocking as the polar vortex weakens dramatically. How the blocking evolves and where the block sets up will be crucial.

[bluewave]

The EPS gradually transitions the main NH blocking from the Kara-Barents regions of Europe over to the Davis Strait  by the 2nd week of January. December featured a very strong block in this region and an intense East Asian Jet which carved out a deep trough over the North Pacific. This lead to the strong Pacific influence that we are experiencing from late December into early January. The shift in heights could allow the North Pacific Jet to buckle and allow a retrogression of the Greenland block. This would represent some improvement by mid-January in the EPO. Sometimes that’s all we need to get the ball rolling toward a MECS regime by mid to late January.

 

 

[LibertyBell]

55 minutes ago, donsutherland1 said:

For the first time, the EPS is now forecasting the zonal mean wind to reverse at 1 mb, 10 mb, and 30 mb. Previously, the reversal was not forecast at 30 mb. If this forecast verifies, this will be a major stratospheric warming event. It will likely have an important impact on the second half of winter, but details as to whether that impact is focused on North America or Eurasia or both remain uncertain.

More than likely, this warming event was the result of the strong blocking that had developed and persisted through much of December. It will likely reinforce the tendency for blocking as the polar vortex weakens dramatically. How the blocking evolves and where the block sets up will be crucial.

Don how strong was the one we had a few years ago that resulted in the four storms in March and one in April?

[LibertyBell]

3 minutes ago, bluewave said:

The EPS gradually transitions the main NH blocking from the Kara-Barents regions of Europe over to Greenland by the 2nd week of January. December featured a very strong block in this region and an intense East Asian Jet which carved out a deep trough over the North Pacific. This lead to the strong Pacific influence that we are experiencing from late December into early January. This shift in heights could allow the North Pacific Jet to buckle and allow a retrogression of the Greenland block. This would represent some improvement by mid-January in the EPO. Sometimes that’s all we need to get the ball rolling toward a MECS regime by mid to late January.

 

 

Kara block....where have we heard that before

[Dark Star]

4 hours ago, bluewave said:

Yeah, this recent study found more frequent SSWs in a warming world.

https://journals.ametsoc.org/view/journals/clim/30/21/jcli-d-17-0044.1.xml

Sudden stratospheric warming (SSW) events influence the Arctic Oscillation and midlatitude extreme weather. Observations show SSW events to be correlated with certain phases of the Madden–Julian oscillation (MJO), but the effect of the MJO on SSW frequency is unknown, and the teleconnection mechanism, its planetary wave propagation path, and time scale are still not completely understood. The Arctic stratosphere response to increased MJO forcing expected in a warmer climate using two models is studied: the comprehensive Whole Atmosphere Community Climate Model and an idealized dry dynamical core with and without MJO-like forcing. It is shown that the frequency of SSW events increases significantly in response to stronger MJO forcing, also affecting the averaged polar cap temperature. Two teleconnection mechanisms are identified: a direct propagation of MJO-forced transient waves to the Arctic stratosphere and a nonlinear enhancement of stationary waves by the MJO-forced transient waves. The MJO-forced waves propagate poleward in the lower stratosphere and upper troposphere and then upward. The cleaner results of the idealized model allow identifying the propagating signal and suggest a horizontal propagation time scale of 10–20 days, followed by additional time for upward propagation within the Arctic stratosphere, although there are significant uncertainties involved. Given that the MJO is predicted to be stronger in a warmer climate, these results suggest that SSW events may become more frequent, with possible implications on tropospheric high-latitude weather. However, the effect of an actual warming scenario on SSW frequency involves additional effects besides a strengthening of the MJO, requiring further investigation.

Thanks for spelling out the abbreviations!

 

[Eduardo]

16 hours ago, bluewave said:

It will be interesting to see if the Bering Sea low can break the all-time record. The last January with a NW PAC low  with a 932 mb pressure or lower was 2013. That also occurred around the time of a SSW. It will be interesting to see if the weeklies are correct about the -NAO retrogression and EPO improvement by mid-January.

https://www.wunderground.com/blog/weatherhistorian/bering-sea-superstorm-bottoms-out-at-924-mb.html

https://csl.noaa.gov/groups/csl8/sswcompendium/majorevents.html

JAN 2013

7-Jan-13

6-Jan-13

7-Jan-13

6-Jan-13

N

E

Both the January 2013 storm and Nuri in 2014 helped establish some pretty incredible -EPO regimes, if memory serves.  EPO-driven patterns can really drop the cold hammer on us.  The 13/14 and 14/15 winters were two of the greatest "deep winters" of my lifetime.  I wouldn't mind a reliving them one bit!

[MJO812]

Gfs is coming on board for next week. Accumulating snow just to the north of NYC.

[SnoSki14]

The hail mary early Jan event could still work out. It's incredibly marginal but a coastal track is favored right now.

I think Euro is way too far inland with this especially since it's coming off the heels of the NY's system which will push the baroclinic forcing east. 

The NY's system acts as a mini 50/50 as well.

[Brian5671]

5 minutes ago, MJO812 said:

Gfs is coming on board for next week. Accumulating snow just to the north of NYC.

 

4 minutes ago, SnoSki14 said:

The hail mary early Jan event could still work out. It's incredibly marginal but a coastal track is favored right now.

I think Euro is way too far inland with this especially since it's coming off the heels of the NY's system which will push the baroclinic forcing east. 

The NY's system acts as a mini 50/50 as well.

temps are marginal though...could be white rain or a car topper

[mikem81]

11 minutes ago, Brian5671 said:

 

temps are marginal though...could be white rain or a car topper

1. Never trust GFS 2m temps.

2. This is as thread the needle as they come anyway as the storm would need to produce its own cold air from 700MB down through 850-925 to BL.

3. Basically need stronger storm in perfect spot. Look at the 12Z Canadian track for example....

[bluewave]

1 hour ago, LibertyBell said:

Kara block....where have we heard that before

Yeah, looks just like the December pattern this year.

https://advances.sciencemag.org/content/4/7/eaat6025

Previous studies have extensively investigated the impact of Arctic sea ice anomalies on the midlatitude circulation and associated surface climate in winter. However, there is an ongoing scientific debate regarding whether and how sea ice retreat results in the observed cold anomaly over the adjacent continents. We present a robust “cold Siberia” pattern in the winter following sea ice loss over the Barents-Kara seas in late autumn in an advanced atmospheric general circulation model, with a well-resolved stratosphere. Additional targeted experiments reveal that the stratospheric response to sea ice forcing is crucial in the development of cold conditions over Siberia, indicating the dominant role of the stratospheric pathway compared with the direct response within the troposphere. In particular, the downward influence of the stratospheric circulation anomaly significantly intensifies the ridge near the Ural Mountains and the trough over East Asia. The persistently intensified ridge and trough favor more frequent cold air outbreaks and colder winters over Siberia. This finding has important implications for improving seasonal climate prediction of midlatitude cold events. The results also suggest that the model performance in representing the stratosphere-troposphere coupling could be an important source of the discrepancy between recent studies.

 

[snowman19]

20 hours ago, Rjay said:

 

Saw Ryan's tweet yesterday.   We know the answer to this.  Just don't tell metsfan. 

Besides the bad PAC, we have this fact, Don warned that this SSW may end up benefiting Eurasia @donsutherland1 @bluewave...

 

[snowman19]

33 minutes ago, mikem81 said:

1. Never trust GFS 2m temps.

2. This is as thread the needle as they come anyway as the storm would need to produce its own cold air from 700MB down through 850-925 to BL.

3. Basically need stronger storm in perfect spot. Look at the 12Z Canadian track for example....

Agree. The GFS has no credibility whatsoever anymore. This is a horrid antecedent airmass and everything would have to literally be 100% perfect, flawless, to get a snowstorm in the metro area. I’ll sell on a snowstorm for Monday

[bluewave]

20 minutes ago, snowman19 said:

Besides the bad PAC, we have this fact, Don warned that this SSW may end up benefiting Eurasia...

 

Something similar happened after the February 2018 SSW. The SPV wound up in Asia. But due to the improvement on the Pacific side, we got the record snows. So the key going forward will be the ability to get a successful NAO retrogression and Pacific improvement.

[MJO812]

3 minutes ago, NEG NAO said:

always trying to find the warm solution............gets annoying after awhile

Exactly

 

[snowman19]

5 minutes ago, NEG NAO said:

always trying to find the warm solution............gets annoying after awhile for your information the GFS is still used by the NWS and has credibility

If you think Monday is a snowstorm setup, I don’t know what to tell you. In fact, it may actually end up being a cutter 

[NEG NAO]

Just now, snowman19 said:

If you think Monday is a snowstorm setup, I don’t know what to tell you. In fact, it may actually end up being a cutter 

did I ever think or say here I thought that Monday is a snowstorm setup ? Why don't you keep an open mind this far out ? The models have been all over the place because that first system has  a  say about what happens with the track of the early next week system and we are still a couple of days away from the first system..........

[SnoSki14]

25 minutes ago, snowman19 said:

Besides the bad PAC, we have this fact, Don warned that this SSW may end up benefiting Eurasia @donsutherland1 @bluewave...

 

SSW can be pretty beneficial for snow chances regardless of where the main cold ends up. 

It will definitely help improve the Pacific side, which would help a ton. Even modest improvements from the Pacific could yield big snows during intense atlantic blocking periods. 

Even better that this would occur during a favorable snow climo period (mid Jan through mid Feb).

[snowman19]

Just now, SnoSki14 said:

SSW can be pretty beneficial for snow chances regardless of where the main cold ends up. 

It will definitely help improve the Pacific side, which would help a ton. Even modest improvements from the Pacific could yield big snows during intense atlantic blocking periods. 

Even better that this would occur during a favorable snow climo period (mid Jan through mid Feb).

How exactly will it definitely improve the PAC? And how does it not matter at all if all the cold ends up on the other side of the pole? 

[binbisso]

7 minutes ago, snowman19 said:

How exactly will it definitely improve the PAC? And how does it not matter at all if all the cold ends up on the other side of the pole? 

With the current setup In the Atlantic with the negative Nao and AO you do not want cold Arctic air as that would only suppress system. + 5 in Canada and plus two here in mid-January through mid-February would work just fine as the block would cause systems to go underneath us and it will be plenty cold enough to snow. I know you know this as you are a knowledgeable poster but you're warm bias interferes with rational judgment and your predictions end up wrong.

[LibertyBell]

55 minutes ago, bluewave said:

Yeah, looks just like the December pattern this year.

https://advances.sciencemag.org/content/4/7/eaat6025

Previous studies have extensively investigated the impact of Arctic sea ice anomalies on the midlatitude circulation and associated surface climate in winter. However, there is an ongoing scientific debate regarding whether and how sea ice retreat results in the observed cold anomaly over the adjacent continents. We present a robust “cold Siberia” pattern in the winter following sea ice loss over the Barents-Kara seas in late autumn in an advanced atmospheric general circulation model, with a well-resolved stratosphere. Additional targeted experiments reveal that the stratospheric response to sea ice forcing is crucial in the development of cold conditions over Siberia, indicating the dominant role of the stratospheric pathway compared with the direct response within the troposphere. In particular, the downward influence of the stratospheric circulation anomaly significantly intensifies the ridge near the Ural Mountains and the trough over East Asia. The persistently intensified ridge and trough favor more frequent cold air outbreaks and colder winters over Siberia. This finding has important implications for improving seasonal climate prediction of midlatitude cold events. The results also suggest that the model performance in representing the stratosphere-troposphere coupling could be an important source of the discrepancy between recent studies.

 

The anomalous Kara Block was also involved in the big turnaround from December 2015 to the HECS we saw in the third week of January in 2016.  It's amazing we had 14 straight hours of 1-2 inches of snowfall and not some fly by night event either, it was a real day time full on blizzard.

[LibertyBell]

27 minutes ago, NEG NAO said:

did I ever think or say here I thought that Monday is a snowstorm setup ? Why don't you keep an open mind this far out ? The models have been all over the place because that first system has  a  say about what happens with the track of the early next week system and we are still a couple of days away from the first system..........

yes I see you are more gungho about mid January onwards which historically is the best time period for snowstorms for us, irrespective of what the so-called "pattern" is.

 

[binbisso]

Today's Canadian has the January 4th system sitting and spinning in the North Atlantic for 5 consecutive days right up to the end of the Run. The model is finally seeing the block and looks like this can set up something in the 10 to 12 day time frame with another short wave in the Gulf and that low sitting in the 50-50 region. The EPS also has something in that time frame. Today's Canadian definitely makes more sense compared to the GFS which has basically cutter after cutter into the block

[LibertyBell]

35 minutes ago, NEG NAO said:

did I ever think or say here I thought that Monday is a snowstorm setup ? Why don't you keep an open mind this far out ? The models have been all over the place because that first system has  a  say about what happens with the track of the early next week system and we are still a couple of days away from the first system..........

fyi I went through the list of the late 80s and early 90s winters and what it proved to me is even in the worst so-called "patterns" this area has EVER had we somehow still managed to score 6-9 inch snowfalls....and if you correct that for higher precip totals we now see in our new climate, it explains why we've been seeing such high intensity precip bombs for the last 10 years or so.  Add to that that it doesn't have to be below normal temp to get big snowstorms here during the most favored period for snow, mid January onwards (some of the aforementioned snowstorms had temps in the 50s and 60s the day prior to the event and again right afterwards- I'm perfectly happy with that!), then it doesn't really matter what the long term so called "pattern" is.  Also I honestly dont give a shit if the entire winter averages 40 degrees or higher, all that matters is that it's in the low 30s when a big storm comes in.  We dont judge winters here by cold, we judge them by inches of snow.  We already had one decent event and one more will get us to average snowfall for the entire winter and that's a lot more than me and many of us were thinking at the start of the season.

[HeadInTheClouds]

51 minutes ago, snowman19 said:

How exactly will it definitely improve the PAC? And how does it not matter at all if all the cold ends up on the other side of the pole? 

maybe you should change your name to rainman19