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Stratospheric Warming event on the way?


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Wxrisk: "Now that the SSW event is fact and the winds have turned its balls to the wall... for someone"

so are the winds favorable or not???? Is this a subjective thing?

Read my CWG piece from a couple of days ago. It still holds. The winds only changed 1 mb, What about the Stratospheric warming event. It certainly reversed the winds at 1 mb but has a ways to go before it reverses the winds at 30 mb. Plus if you look at the EP flux vectors, they start pointing more strongly towards the south (left) towards the end of the period just about the time that the 30 mb zonal wind decrease levels off. We have not had a wind reversal at 30 mb. The warming may have helped with the high heights over the north Pacific that have built locally but this still is not yet the big kahuna. It might end up being that but so far, it isn't.

post-70-0-29951400-1326049453.gif

Buckeye, you want the ep flux vectors pointing towards the ploes (the right). You want to see the winds turn at 30 mb and they are still westerly

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The signal is even stronger today than yesterday. That's why I'm not yet buying the euro negative nao look. Usually most of the early changes are not in the north atlantic if I remember the typical progression from the composites. Plus the ens means don't really yet show it going negative. Anyway, this warming event is a great opportunity to learn.

I agree the -NAO looks premature on modeling, seems like there is a building consensus of an alaskan ridge popping up to the arctic circle though?? EP flux aside, the -AO sourced from the Russian influx makes sense to occur before the -NAO, no?

I feel that might be all we need to see happen before the dice start gradually falling in the right direction. The deep negative in eastern Canada is what makes me think the east needs to wait another 3 weeks before sustained cold arrives. I think I've seen SSWings occasionally downwell with an iffy zonal wind setup before?

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Excellent excellent read one which i agree with but so many are saying there is a MAJOR SSW going on and it has reached the 500 mb level and the winds at 30 mb levels have reversed etc etc....

Supposedly all the energy mets are saying this ....

Not HAS. WILL.

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Not HAS. WILL.

And this is based on?

I hope its much more then a gut feeling....

I guess I will post the question here I have posted elsewhere (not on this forum)

IF the EP flux vectors are pointing towards the equator and not towards the pole...then what guarantees that it will reverse? My understanding is that you want them to point towards the pole for a propagating downward MAJOR SSW to effect the 500 mb level....

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And this is based on?

I hope its much more then a gut feeling....

I guess I will post the question here I have posted elsewhere (not on this forum)

IF the EP flux vectors are pointing towards the equator and not towards the pole...then what guarantees that it will reverse? My understanding is that you want them to point towards the pole for a propagating downward MAJOR SSW to effect the 500 mb level....

I don't think there is any guarantee at least from the articles I've seen. Maybe Jorge or HM might have some insight.

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The SSW itself may do the job eventually but hard to expect it so soon?

One positive is this winter as we've get closer to warmings the EP flux has turned out slightly more poleward than forecasted in the longer range.

I'm a novice on this topic, but my understanding has always been that a +QBO prevents the anomalies from propagating, while downward propagation is more common in a -QBO. I just checked and the 30mb level has gone strongly negative while the 50mb is trending downward and will probably turn negative this month. In that framework, then it sounds like a timing issue, and the SSW would need to occur later rather than sooner to have the best chance of propagating.

I have never seen anything on the SSW itself creating its own favorable environment for downward propagation. Is that what you are saying you expect? Like I said, I don't know anything about the topic, but I guess the SSW is expected to be capable of eliciting the small change in 50mb winds (for example) that will be needed in order for it come down?

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I'm a novice on this topic, but my understanding has always been that a +QBO prevents the anomalies from propagating, while downward propagation is more common in a -QBO. I just checked and the 30mb level has gone strongly negative while the 50mb is trending downward and will probably turn negative this month. In that framework, then it sounds like a timing issue, and the SSW would need to occur later rather than sooner to have the best chance of propagating.

I have never seen anything on the SSW itself creating its own favorable environment for downward propagation. Is that what you are saying you expect? Like I said, I don't know anything about the topic, but I guess the SSW is expected to be capable of eliciting the small change in 50mb winds (for example) that will be needed in order for it come down?

I'm a first year met student and don't know much about it either, but the winds at 1mb flipped around once the second wave began developing. Most of my "forecasting", if you can call even it that, is derived from a solar based method relating the Sun and Earth energy bodies which is something I have studied on my own, since it isn't mainstream science. But if I'm correct there will be no way to avoid an eventual forcing of the cold air into the USA, coming in about 20 days, with a deep trough in the east reverting to a classic La Nina gradient by mid March.

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Read my CWG piece from a couple of days ago. It still holds. The winds only changed 1 mb, What about the Stratospheric warming event. It certainly reversed the winds at 1 mb but has a ways to go before it reverses the winds at 30 mb. Plus if you look at the EP flux vectors, they start pointing more strongly towards the south (left) towards the end of the period just about the time that the 30 mb zonal wind decrease levels off. We have not had a wind reversal at 30 mb. The warming may have helped with the high heights over the north Pacific that have built locally but this still is not yet the big kahuna. It might end up being that but so far, it isn't.

post-70-0-29951400-1326049453.gif

Buckeye, you want the ep flux vectors pointing towards the ploes (the right). You want to see the winds turn at 30 mb and they are still westerly

Where do you obtain these images from and what about the 90 MB level EP Flux vectors? I read that they are pointing towards the poles and not the equator...

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I'm a first year met student and don't know much about it either, but the winds at 1mb flipped around once the second wave began developing. Most of my "forecasting", if you can call even it that, is derived from a solar based method relating the Sun and Earth energy bodies which is something I have studied on my own, since it isn't mainstream science. But if I'm correct there will be no way to avoid an eventual forcing of the cold air into the USA, coming in about 20 days, with a deep trough in the east reverting to a classic La Nina gradient by mid March.

Would you provide the data that causes this to happen? We have been in a warm pattern for a long time. Statistically speaking the odds of it going on much longer than 20 days would be pretty rare. Which coorelates well with what your saying. But you should provide your data on this. If there is real physical forcings out there that you are speaking of. Then it should be presented.

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Would you provide the data that causes this to happen? We have been in a warm pattern for a long time. Statistically speaking the odds of it going on much longer than 20 days would be pretty rare. Which coorelates well with what your saying. But you should provide your data on this. If there is real physical forcings out there that you are speaking of. Then it should be presented.

Well be specific, what exactly are you looking for? Analogs, qualitative evidence, quantitative evidence, or something else?

This might be better suited for the "All Solar Thread" in the CC forum at risk of pulling this great thread off topic with controversial theory and irrelevant physics.

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My thinking as of now is that EP flux vector direction will have less importance than what it usually does. The stratospheric PV will take a major blow, with a 1-2 punch in a very short period of time. Yesterday's Euro analysis shows healthy westerly winds in a good deal of the whole tropo-strato column from 60N-90N, with 20-35 m/s westerly winds in the whole stratosphere from 60-70N. By day 5 and up to day 10, there's no more than 10-15 m/s in pockets, with a good deal of easterly winds.

Fig.1 Yesterday's analysis. Notice the dominance of the reds for most of the 60-90N column.

YsBjc.gif

Fig 2. By day 5, a strong warming is making it's way down in the upper troposphere. Notice how winds from 60N-90N are <20 m/s in the whole column

SzzWe.gif

Fig 3. By day 9, another strong warming is forecasted to make it's debut...it's even more dramatic than the first one. The column now is < 15 m/s... And there's indications of strong ridging in the troposphere (which is also shown in the 0z Euro as the -WPO and Siberian ridge)

4gAIL.gif

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My thinking as of now is that EP flux vector direction will have less importance than what it usually does. The stratospheric PV will take a major blow, with a 1-2 punch in a very short period of time. Yesterday's Euro analysis shows healthy westerly winds in a good deal of the whole tropo-strato column from 60N-90N, with 20-35 m/s westerly winds in the whole stratosphere from 60-70N. By day 5 and up to day 10, there's no more than 10-15 m/s in pockets, with a good deal of easterly winds.

Fig.1 Yesterday's analysis. Notice the dominance of the reds for most of the 60-90N column.

YsBjc.gif

What are the implications on sensible weather in the US if this ferries?

Fig 2. By day 5, a strong warming is making it's way down in the upper troposphere. Notice how winds from 60N-90N are <20 m/s in the whole column

SzzWe.gif

Fig 3. By day 9, another strong warming is forecasted to make it's debut...it's even more dramatic than the first one. The column now is < 15 m/s... And there's indications of strong ridging in the troposphere (which is also shown in the 0z Euro as the -WPO and Siberian ridge)

4gAIL.gif

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We need east and west blocking to squeeze the air down this way.

Yep, especially the west blocking... the east blocking would help to bottle it down east of the Rockies.

Thanks. It seems like we will have west blocking. Without the east blocking to go along with this, the gradient pattern will remain too far to the north, correct?

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Great read in here and a really nice article Wes. I continue to be encouraged going forward with the pattern changing, the AO going negative and what not... It's a possibility the AO will tend to stay negative for the next few weeks and all especially if the straospheric trends continue to cooperate, but Wes, HM and others make an important point when they say this doesnt guarantee the sustained cold is going to favor the east for the rest of the winter. The tropical forcing, perhaps La Nina among others will likely help determine where to place the cold anomolies rushing southward towards the mid-latitudes.

With the NAO aspect looking to remain positive for the time being along with the variability in the mean trough placement, it should continue to be difficult to find a window for any significant winter storm in the mid-Atlantic region I would think. Light-moderate events can be a more reasonable expectation though and hopefully we get some soon!

I'm interested to see where we go with the NAO in the coming weeks. It is well documented how the state of the AO and NAO are correlated to go hand in hand with one another (supposedly a 0.83 correlation during the winter), so you wonder if the NAO will go negative next in response to the AO shooting negative. Then again, it should also be noted the AO has a strong interconnection with troposphere/stratosphere variability while the NAO is primarily confined to the troposphere. if we are to believe the ongoing warm waves in the stratosphere are assisting in the upcoming -AO signal, then perhaps the -NAO correlation does/will not apply in this instance.

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I'm interested to see where we go with the NAO in the coming weeks. It is well documented how the state of the AO and NAO are correlated to go hand in hand with one another (supposedly a 0.83 correlation during the winter), so you wonder if the NAO will go negative next in response to the AO shooting negative. Then again, it should also be noted the AO has a strong interconnection with troposphere/stratosphere variability while the NAO is primarily confined to the troposphere. if we are to believe the ongoing warm waves in the stratosphere are assisting in the upcoming -AO signal, then perhaps the -NAO correlation does/will not apply in this instance.

Or may apply even more. If the strat warming is causing the AO to go negative, then I think it would follow that if there is such a tight correlation between the AO and Strat shenanigans then it would make sense the NAO would also follow to some extent.

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Or may apply even more. If the strat warming is causing the AO to go negative, then I think it would follow that if there is such a tight correlation between the AO and Strat shenanigans then it would make sense the NAO would also follow to some extent.

Not sure how it "should" play out, but in this instance we do have the models holding firm on a +NAO look despite the AO going negative. My point was that the AO itself is more connected to troposphere/stratosphere coupling. The NAO branch is not correlated well with the stratopshere at all, rather just tropospheric influences forcing a block up into Greenland.

So in essence what I'm saying is if there is an instance where the AO goes negative and the NAO remains positive, perhaps this is a situation for that.

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