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Sudden Stratospheric Warming Begins! Significant Cold Ahead For January-February:CROSS POLAR FLOW !

poleshiftnow

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QVectorman

QVectorman

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one thing i find interesting, maybe a met can answer this. I notice that in Russia where they've had the vodka cold, a large hot high sits over that area in the stratosphere. Am I correct in assuming that since the strat is hotter in that location, that is why it's colder below? I guess the real question is... are the coldest surface temps BELOW the hottest strat temps. It kinda appears that way. If so, it's expected to warm in the strat over the US.

 

It's where the PV use to be...meaning a wall of strong winds was there blocking the intrusion of 03 from the tropics and now it's where the winds have decreased and an increase in 03 has accumulated and warmed the strat. I believe it's more correlated to where the initial major tear in the PV took place (caused by mtn waves etc breaking into it from below) so the cold air spills down and out to the lower atm. immediately below it (for lack of better explanation). So after that the warm pocket is more of an artifact of the hole in the PV (the higher concentration of 03 (warmer strat air) just gets propagated along with the circulation) rather than a leak/tear that keeps squirting out cold air. And the cold air itself is propagated along at the surface by the tropo. weather pattern. So the sfc cold air become disconnected from the strat. air pattern and becomes controlled by the tropo. pattern....After the initial tear. Look up some maps and notice the same 10 mb strat. temps above the area off the coast of Maine doesn't have the same magnitude of cold at 500/850H levels. And on your map at 30mb the strat temps are only elevated above Siberia..no where else yet on the globe. This is where the hole has been torn all the way down to the 30mb level and 03 has filled in the hole leaving a warm signature but the cold air is pouring down to the sfc below since this has just started taking place (@30mb)...for this episode of cold for Siberia the past several days.  Notice the 10mb and 30mb warming as you mentioned the extreme cold below it (on the map in Siberia) only matches up to the 30mb warm pocket in Siberia. 

 

post-3697-0-58241300-1357502958_thumb.jp

 

 

This is my understanding of it. Maybe HM knows more. 

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wxmx

wxmx

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Looks like this event, if not one of the strongest magnitude wise, it will be one of the longest, with stratospherical temps above normal for an extended period of time. Rewarming just occurred and it looks like a definite propagator in the long range. This warming was probably induced by type 2 & 3 waves, which are more favorable for propagating and PV splitting events

 

Renewed warming starting at the upper stratosphere

post-29-0-24730700-1357916991_thumb.gif

 

Wave 2 amplitudes might have triggered this warming phase

post-29-0-43249900-1357917158_thumb.gif

 

All 10 days show mostly easterly winds above 60N on the whole stratosphere/troposphere column, high latitude anomalous high heights (ridging).

post-29-0-91403000-1357917221_thumb.gif

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GaWx

GaWx

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wxmx,

 I do see that after a very slight dip, warming has resumed including at the 10 mb level these last two days. It is approaching the +20 C level at 10 mb. You previously seemed to think it had about peaked. What do you think now? It still needs to reach ~+28 C at 10 mb to be on par with other very strong events like 1/1985 in terms of highest anomalies fwiw. At still only +18 C, it isn't all that impressive yet in terms of strongest events. It is now up to ~+23 C at 2 mb fwiw. So, maybe that's where 10 mb is at least headed. In terms of downstream effects, it is hard to say whether or not that actual max. is all that important, but 1/1985 was one of the strongest and quickest. It came on extremely quickly (much more quickly than the current one) and was over in only about six days! This one is going to be much longer, but I don't know the implications of that vs. a very short one like 1985.

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DaculaWeather

DaculaWeather

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I think the new increase in pressures, temps, and a speedier reversed wind speed (now 70 mph) leans toward a more prolonged event Larry. Of course I'm not a met and hopefully they'll have better insight. 

 

I am impressed with all the anomalies and peaks for far though. In looking back, it's been a while for a real good event.

 

time_pres_TEMP_ANOM_JFM_NH_2013.gif

 

time_pres_UGRD_ANOM_JFM_NH_2013.gif

 

time_pres_HGT_ANOM_JFM_NH_2013.gif

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GaWx

GaWx

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I think the new increase in pressures, temps, and a speedier reversed wind speed (now 70 mph) leans toward a more prolonged event Larry. Of course I'm not a met and hopefully they'll have better insight. 

 

I am impressed with all the anomalies and peaks for far though. In looking back, it's been a while for a real good event.

 

Steve,

 Thanks.

 

1)  I do wonder about the longevity vs. strength. 1/1985 was very short (only ~6 days) but very strong. Maybe shorter would be better for whatever reason?? I don't know. Your thoughts?

 

2)  Didn't we just have one in 1/2012?

 

3) Yes, the current one is one of the more impressive reversed wind speeds....about on par with 1/1985 and the other four that warmed to +28C at 10 mb. However, I don't know the importance of this vs. the importance of peak warming. Maybe you know more than me. Maybe this means the warming will continue a bit further as I think you're saying?

 

4) I may post a new thread today in the SE forum about five events warmer than +28 C at 10 mb and how the weather was at KATL afterward fwiw.

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DaculaWeather

DaculaWeather

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i'd like to read that. 

 

The one we had last year never propagated down. It just kind of fizzled. Majors happen roughly every two years though. 

I understand that duration and strength are the two main players in the damage done. I also understand that the longer the duration, the better chance that the PV stays in a state of disorganization versus recombining. 

 

Again... just learning myself. I did find quite a few papers on it (still going through those) but this is a good one: http://www.meteo.psu.edu/~fcstmgr/stratwarm.pdf

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GaWx

GaWx

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i'd like to read that. 

 

The one we had last year never propagated down. It just kind of fizzled. Majors happen roughly every two years though. 

I understand that duration and strength are the two main players in the damage done. I also understand that the longer the duration, the better chance that the PV stays in a state of disorganization versus recombining. 

 

Again... just learning myself. I did find quite a few papers on it (still going through those) but this is a good one: http://www.meteo.psu.edu/~fcstmgr/stratwarm.pdf

 

Steve,

 I just read that entire paper. Very informative and easy to follow. The cyclone frequencies makes sense as you'd expect a decrease within the Arctic air inland in the E US and an increase near the southern boundary in the GOM that then go across FL to up just off of the east coast....so, it sounds good for increased Miller A chances.

 

 One thing is bothering me a lot: does the current warming even qualify yet as major? I have a lot of doubt as it has still only risen to ~-38 C at 10 mb according to two sources I've seen. This paper defines a major SSW as one with it rising to warmer than -35 C at 10 mb. Keep in mind that I was already questioning the intensity being high enough in earlier posts even before reading this paper. It may get there soon since the warming has resumed, but it hasn't yet.

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wxmx

wxmx

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As I have stated before, the most accepted definition of a MWW uses wind direction and magnitude and not temperatures, which makes more sense when talking about the night polar jet. Using that, this is indeed a MWW. Last year's wasn't, IIRC

 

I haven't come across papers that talk about duration instead of magnitudes, but it makes sense that having a weaker PV for longer would help odds about longer lasting colder than average temps in the midlatitudes. But don't quote me about that.

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DaculaWeather

DaculaWeather

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You're going to see a lot of gyrations for a while before things settle down. The upper levels are still warming significantly and the 30 hPa winds are getting ready to reverse if they haven't already. All the winds above 30 hPa have completely reversed and now moving along at a pretty good clip (~60-70mph at 1hPa)

 Still more changes for the strat... 

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GaWx

GaWx

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As I have stated before, the most accepted definition of a MWW uses wind direction and magnitude and not temperatures, which makes more sense when talking about the night polar jet. Using that, this is indeed a MWW. Last year's wasn't, IIRC

 

I haven't come across papers that talk about duration instead of magnitudes, but it makes sense that having a weaker PV for longer would help odds about longer lasting colder than average temps in the midlatitudes. But don't quote me about that.

 

Today, the warming ceased again and it is only at -38 C at 10 mb with only a +18 C anomaly. I think that at the very least this means it is on the weak side of a major event considering that some have been over +32 C!

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wxmx

wxmx

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Today, the warming ceased again and it is only at -38 C at 10 mb with only a +18 C anomaly. I think that at the very least this means it is on the weak side of a major event considering that some have been over +32 C!

In the end, what really interests us are the pressures/heights in the troposphere (higher heights/pressures above 65N usually means colder for the midlatitudes).

 

Here's how they look like in a propagating MMW

 

time_pres_HGT_ANOM_JFM_NH_1985.gif

time_pres_HGT_ANOM_JFM_NH_2009.gif

 

and in a run of the mill minor SSW

time_pres_HGT_ANOM_JFM_NH_2012.gif

 

So far:

time_pres_HGT_ANOM_JFM_NH_2013.gif

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wxmx

wxmx

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Based on what I'm seeing, and please correct me if I'm wrong, this one is doing pretty good. One thing I had been noticing was the extreme pressure anomalies. 

Yep, it appears that way. You can also see this one has been  of longer duration in the upper stratosphere, which would, by common sense, mean it's better to keep the PV weak, and higher heights in the long run. You can also notice, that there are phases in the troposphere where ridging waxes and wanes, the first one is almost immediate with the SSW, the 2nd one is around 10-20 days later, which would match well with the progged tank in the AO in the last week of January.

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