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Blizzardof96 surely you are not suggesting that we will see a FW (final warming) before years

end as this is would be imposible. Also when using abbrivations it is helpful to show what they

mean in brackets for those not familiar with stratospheric events etc, such EAMT which I take

it is east Asian mountain torque.Cheers.

 

The synoptic charts certainly do look as if they mean business in trying to pump heights

into the Arctic from the Pacific side. A good mountain torque brought about by a strong

MJO event (Madden-Julian Oscillation) or Asian mountain torque could very well see the

dame break.  Hopefully this is more a case of when rather than if but once this happens

it could very well be game on.

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I have reposted this image posted a couple of days back of the northern

hemisphere 10hpa temperatures.

In the last three days or so a warming has developed over the southeast

corner of north America and is growing.

Certainly something to watch.

post-10506-0-27116300-1383410467_thumb.g

Edited by cooling climate
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Blizzardof96 surely you are not suggesting that we will see a FW (final warming) before years

end as this is would be imposible. Also when using abbrivations it is helpful to show what they

mean in brackets for those not familiar with stratospheric events etc, such EAMT which I take

it is east Asian mountain torque.Cheers.

 

The synoptic charts certainly do look as if they mean business in trying to pump heights

into the Arctic from the Pacific side. A good mountain torque brought about by a strong

MJO event (Madden-Julian Oscillation) or Asian mountain torque could very well see the

dame break.  Hopefully this is more a case of when rather than if but once this happens

it could very well be game on.

No i am not suggesting that at all... but a late season warming is something you look for in low solar/+QBO years whether its a FW or just a late winter SSW. I will try to add brackets to abbreviations when possible in the future and yes EAMT does stand for east asian mountain torque. Cheers.

Edited by blizzardof96
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ecm wave 1 temps continue to show moderate increase all the way down to 10hpa with associated geopot.  some activity is better than no activity and i note that the trop models currently show no urgency to get any core of the vortex to be resident around central/southern greenland.  

Edited by bluearmy
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In terms of its impact on the stratosphere does anybody know what the impact of GLAAM dropping through the floor does for us.

I know that strong ENSO events can feedback into the stratosphere through planetary wave propagation and dissipation. This tends to be reduced in neutral ENSO conditions. When tropical AAM drops through the floor or rises dramatically then I would think that there will be some feedback due to the change in global circulatory pattern and altered wavelengths- the strongest of which we know can affect the strat.

 

Longer term the ENSO state affects the BDC.

 

http://www.atmosp.physics.utoronto.ca/SPARC/SPARC2008GA/Posters/SessionA_P11_A299_Calvo.pdf

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Great analysis by Ethan in that blog post, from the Mitchell presentation on the publications page, see link in Teleconnection paper thread by Interitus. This chart has a longer term look at the trend.

 

January is the month to watch..

post-7292-0-39100500-1383573921_thumb.pn

 

Edit - correcting typo.

Edited by lorenzo
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One area of hope for continuing wavebreaking is those Alutieun heights but at the moment nothing significant is forecasted.

 

Well, I would say just the opposite. Posted Image Both GEFS and ECMWF are forecasting a phenomenal blocking to develop over Aleutian islands in the 8-10 day period. Considering this is in ensemble 240h period, such anomalies are really significant.

 

Posted Image Posted Image

 

 

 

Posted Image Posted Image Posted Image

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Yeah it can be seen in the PNA it's expected to dive into a strong negative phase, which suggests strong blocking over the North Pacific. Anomalous high pressure over this region brings enhanced wave-2 activity and this can be seen for the first time on the Berlin models. We're looking at some pretty strong wave breaking in 7-10 days just after the wave-1 activity begins to weaken.

 

 

http://users.met.fu-berlin.de/~Aktuell/strat-www/wdiag/figs/ecmwf1/ecmwfzm_ha2_f216.gif

 

 

Some small bursts of warming over Canada in the lower stratosphere have already put wobbles into the the lower vortex and I'm guessing they're the reason for the change to cool zonal, even very brief meridional patterns.

 

Edit: Can we not post picture files from our computer anymore?

Edited by Snowy L
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I hope you are onto something guys and we see some disruption but i am reporting the latest forecasts out to day 10

and although both wave 1 and 2 activity is shown there is no evidence of anything significant yet.

The image of the 500hPa blocking posted by Rectros looks impressive but if this is to have any influence higher up it will be beyond the day 10 forecasts i have shown.

We do see frequent modeling of the Aleutian troshopheric heights at this time of year-look in the archives- but unfortunately they often flatter to deceive and many of them hardly touch the cooling vortex.

 

Still now and then we get a result-time will tell.Posted Image

Edited by phil nw.
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 Hi Rectros,

Further to my post above and after re-reading yours i think a misunderstanding.

When i said nothing significant for those heights i was referring to the effect on the Stratosphereic vortex within 10 days.

Of course i had already seen the trophospheric height forecasts that you posted.

I have edited my OP to hopefully clarify.Posted Image

 

Regards,Phil

Edited by phil nw.
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If we take a look at +QBO years where we saw no major SSW's events from Dec-March at 30mb we get this pattern at 500mb. Notice the suppressed heights over the tropics which is probably indicative of above normal stratospheric temps across this area. Their is also a fairly neutral NAO signal with a strong bering sea ridge. When we see a strong bering sea ridge coupled with a neutral or positive NAO it really goes against any WAVE 1 or 2 warming's. This is why any major warming of the strat looks unlikely until we can get out of this current pattern. 

 

post-21067-0-49504000-1383617485_thumb.p

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Interesting update at http://torontowxcenter.blogspot.co.uk/

Please take a look at http://forum.netweather.tv/topic/72635-the-seasonal-forecast-thread/page-23#entry2826741

The guys behind the OPI have made their preliminary forecast for 2014. Use e.g. google translate, it's written in Italian.

Are they forecasting a +ve Arctic Oscillation

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As things stand there is no sign of anything 'significant' worth mentioning for this thread, that is nothing that represents a threat to the stratospheric vortex's integrity.

 

The pacific ridge being circular adds nothing to the party.

 

I see a slight weakening at day 8-10 but only through natural variation rather than any significant forcing. -

 

I think we are circa 21 days plus before there is any hope for movement on this thread.

In the mean time sit tight.

Agreed, startospheric set up will be conducive to 'classic' zoneality with jet shifted north taking us into December

 

BFTP

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That's a bit of kick in the baubles for us Matt, still there's always hope of a January 84 type set up I suppose. I'm still not convinced we won't see a colder than average December as I feel using the state of the QBO can be  misleading when one looks back at how cold winters can still be achieved during +QBO phase.

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