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Edited by knocker
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Surprised nobody seemed to notice the crazy northern blocking on the 31/10 18z GFS. Anyway here is the stratospheric hydrostatic response -

1167604005_NH_HGT_10mb_32418103118.thumb.gif.ac6140b0b6b14e726eab9b354ae46f7d.gif

328904772_NH_HGT_10mb_384181031.thumb.gif.2e445d5bed909472caa25917720d734c.gif

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Amazing end of the gfs op run in the mid to upper strat as the sceuro ridge shows up at levels I’ve rarely seen on a strat chart ..

here at 30hpa .....caveat -  this is the gfs op 

BBB7962A-E63E-4F43-AE10-B81A63F52308.thumb.jpeg.9abc58753c3eb58602ce7921bd7d5daa.jpeg

Edited by bluearmy
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Edited by knocker
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Gefs are now keen to restore an average (at least) strength upper vortex by the end of week 2. 

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QBO negative for the last month -2,79. 

https://www.esrl.noaa.gov/psd/data/correlation/qbo.data

 

Scatter diagrams of the monthly mean 30-hPa geopotential heights (geopot.km) in February at the North Pole (1942 till 2007), plotted against the 10.7 cm solar flux. Left: Circles: years in the east phase of the QBO (n = 29). Right: Squares: years in the west phase (n = 37). The numbers indicate the respective years, with WE in red and CE in blue. Filled symbols denote MMWs. r = correlation coefficient; H gives the mean difference of the heights (geopot.m) between solar maxima (200 s.flux units) and solar minima (70 s.flux units). (Reconstructions: 1942 till 1947; NCEP/NCAR re-analyses: 1948 till 2007.) (van Loon and Labitzke (1994), updated.)

Scatter-diagrams-of-the-monthly-mean-30-hPa-geopotential-heights-geopotkm-in-February.png

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https://twitter.com/webberweather/status/1059473581678231552

West QBO has descended below 30 hPa but the lower stratosphere remains in an eQBO favoring tropical tropopause upwelling & upward propagation of Kelvin Waves to the westerly shear zone. Worth re-iterating that SSWEs occur most often during an eQBO >> wQBO transition.

Edited by sebastiaan1973
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8 minutes ago, sebastiaan1973 said:

https://twitter.com/webberweather/status/1059473581678231552

West QBO has descended below 30 hPa but the lower stratosphere remains in an eQBO favoring tropical tropopause upwelling & upward propagation of Kelvin Waves to the westerly shear zone. Worth re-iterating that SSWEs occur most often during an eQBO >> wQBO transition.

Thanks Seb, i didn't know occur most often during the Qbo transition !! Hopefully we get the early season SSW..

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8 hours ago, Glacier Point said:

Some useful tropospheric developments upcoming which are likely to have stratospheric impacts towards the end of November and more particularly into December.

A strong convectively coupled tropical wave is being forecast to develop in the Indian Ocean in the next week and migrate eastwards during week 2 (MJO phase 2-3-4-5 transition).

twc_globe_mjo_vp200.thumb.png.1a132c0267baab2470b9ffb054892189.png

We are likely to see jet extension and subsequent retraction of the Asian and Pacific Jets leading to a increase in tendency in relative angular momentum and the GWO spiking phases 4 and 5. Mountain torque territiory for the Himalayas.

At the same time, long wave pattern over eastern Europe maintains a favourable Wave 2 projection. This is likely to be enhanced over time as the amplification resulting from retraction of the Pacific Jet works its way downstream. 

gfs-ens_z500aMean_nhem_1.thumb.png.2c77997cce457fad0da4391422cf00e1.pnggfs-ens_z500aMean_nhem_6.thumb.png.6e4198c3180b6bf33bd3582012be6d48.pnggfs-ens_z500aMean_nhem_11.thumb.png.8477afc3c977e4b82eda15e9f33801ad.png

Both tropical wave and resultant wave 2 look very similar to 1986 evolution.

198610.phase.90days.thumb.gif.f1317cde8bf9278b8eec50afb22a5eec.gif

The AO looks to be tanking +ve in the week 2 timeframe, ideal for wave activity flux (again similarities with Nov 1986 there).

E3FVAIVnDF.thumb.png.f99cf73f70bacfb2af688447414b3408.png

So bottom line is ingredients for stratospheric vortex being significantly weakened during latter part of December.

Was going to comment on this myself. The last two waves have taken 30-50 days with one forecast to develop in the Indian Ocean now. 

u.anom.90.5S-5N.gif

u.anom.30.5S-5N.gif

GEM the most amplified with the tropical cycle..

CANM_phase_20m_small.gif

GFS going straight back to phase 8. 

diagram_40days_forecast_GEFS_member.gif

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9 hours ago, Glacier Point said:

Some useful tropospheric developments upcoming which are likely to have stratospheric impacts towards the end of November and more particularly into December.

A strong convectively coupled tropical wave is being forecast to develop in the Indian Ocean in the next week and migrate eastwards during week 2 (MJO phase 2-3-4-5 transition).

twc_globe_mjo_vp200.thumb.png.1a132c0267baab2470b9ffb054892189.png

We are likely to see jet extension and subsequent retraction of the Asian and Pacific Jets leading to a increase in tendency in relative angular momentum and the GWO spiking phases 4 and 5. Mountain torque territiory for the Himalayas.

At the same time, long wave pattern over eastern Europe maintains a favourable Wave 2 projection. This is likely to be enhanced over time as the amplification resulting from retraction of the Pacific Jet works its way downstream. 

gfs-ens_z500aMean_nhem_1.thumb.png.2c77997cce457fad0da4391422cf00e1.pnggfs-ens_z500aMean_nhem_6.thumb.png.6e4198c3180b6bf33bd3582012be6d48.pnggfs-ens_z500aMean_nhem_11.thumb.png.8477afc3c977e4b82eda15e9f33801ad.png

Both tropical wave and resultant wave 2 look very similar to 1986 evolution.

198610.phase.90days.thumb.gif.f1317cde8bf9278b8eec50afb22a5eec.gif

The AO looks to be tanking +ve in the week 2 timeframe, ideal for wave activity flux (again similarities with Nov 1986 there).

E3FVAIVnDF.thumb.png.f99cf73f70bacfb2af688447414b3408.png

So bottom line is ingredients for stratospheric vortex being significantly weakened during latter part of December.

I know what happened in mid jan 87 but dec 86 was a bit of a right off for cold weather fans. Even towards the end. 

archivesnh-1986-12-30-0-0.png

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1 minute ago, blizzard81 said:

I know what happened in mid jan 87 but dec 86 was a bit of a right off for cold weather fans. Even towards the end. 

archivesnh-1986-12-30-0-0.png

Sorry to digress but surely you'd take a December 86 in order to achieve a Jan 87!!!!!!!

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2 minutes ago, feb1991blizzard said:

Sorry to digress but surely you'd take a December 86 in order to achieve a Jan 87!!!!!!!

Mmmm! Err, I think I could just about stomach the December - Just lol

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A little hickup or is it a start of something?

pole30_nh.thumb.gif.b6e4e737681fc9794a6f994e13f7fe89.gifpole10_nh.thumb.gif.9bd4e1e46fcf01b83460c66c07b6b5d8.gif

tlat_u30_nh.thumb.gif.2bc1df49c330e5183c4427146d55d26d.giftlat_u10_nh.thumb.gif.8d742b0f036223ac134fa72582fd37d1.gif

 

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52 minutes ago, Allseasons-si said:

A little hickup or is it a start of something?

pole30_nh.thumb.gif.b6e4e737681fc9794a6f994e13f7fe89.gifpole10_nh.thumb.gif.9bd4e1e46fcf01b83460c66c07b6b5d8.gif

tlat_u30_nh.thumb.gif.2bc1df49c330e5183c4427146d55d26d.giftlat_u10_nh.thumb.gif.8d742b0f036223ac134fa72582fd37d1.gif

 

Stewart highlights reasons to be optimistic looking ahead but over the next couple weeks there isn’t much on the strat forecasts to drive much interest as the upper strat cranks up again 

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1 hour ago, bluearmy said:

Stewart highlights reasons to be optimistic looking ahead but over the next couple weeks there isn’t much on the strat forecasts to drive much interest as the upper strat cranks up again 

This was posted in the tweets thread earlier

 

as you say,nothing much of note in the next week or so but the final third of nov could prove of a worthy note.

Edited by Allseasons-si

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Good discussion developing here and given the Strat Trop telling different stories - really is a new year in terms of meaningful analogs.

Short Version of post - Some H5 and 10 hPa projections based on existing 'known' stuff.

QBO swtiches at this point of the season it would seem throw the rule book out the window. In terms of QBO data we have the top of the strat rampantly westerly, the 30hPa level just seeing that Westerly impact pull through and below this nearer the trop a strong Easterly regime continues.

Courtesy of some help from @Interitus patiently guiding me through the IT stuff for Panoply, went building some plots. The usual view of composites or analogs built on ESRL can be exported NCDF and plugged into the Panoply machine and hey presto - you get some charts that are in short a hell of a lot prettier to look at.

Attached below are H500 based on some loose parameters from 1979 to date ( start point for strat data). The method in the madness is considering Ant Mas post around 800m waves and their further inflection down the road as winter progresses, using that as a base added in Solar activity being very low, the projected MJO phases from GP above and a really loose positve ENSO filter, it looks like within the thermocline that it might come on like a train but still we shall see. Specifics annotated on the charts.

As a result you get this for the 2nd and 3rd periods in November and then using the ( add days function on ESRL) a rough picture of direction of travel.

So, in essence some composites for remainder of November, central date being 20th,  then a future view with a central date of 10th Dec.

834719732_H500Composite.thumb.png.254605ca7ce71555f51795805421f197.png1390198030_H500plus20.thumb.png.dd9f009167679b3bb8da7540048fb406.png

1529636202_10hPaComposite.thumb.png.b4cfc94a09c6a8e046be4427452fba78.png1474880546_10hPaCompositeplus20.thumb.png.5d80201f9ef1f5d5c84fc5ea1572b5fc.png

This is predicated on the W1 activity exceeding 800m - if it doesn't then null and void - rest of parameters am okay with. In terms of Vortex Intensification and it's cycle of moving from developing > onset> mature then declining. I need to dig out the paper that shows this on a temporal basis ( lost a hard drive).

If VI period is in earnest then any potential signature Strat event I see as kicked down the road until Jan. Meanwhile the easterly regime in the trop would lead to tropics nuances creating fun until that time.

Any thoughts welcome on methodology given this is now set up to plot cool stuff... 

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Great job Lorenzo!

If I can make a suggestion: Reduce the amount of lon/lat lines to 90x30 interval, since for this type of data it is not as important and can sometimes even be a distraction. 

Also, you have an important flaw in the color scaling. You dont have zero centered colour scale, which is critical when plotting anomalies. That means that the colour scaling is centered on zero, so all negatives are on one side and positives on the other. Basically you must have 0 value in the white middle. One plot has colour bar from -80 to 60 for example, which means that the zero lands in the red colour so you get more red colour on the plot than there should be. When plotting anomalies you need to have mirrored values in the colour bar, like -80/80, or -40/40, so you get zero in the middle and colours represent proper anomaly values. 

Edited by Recretos
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Cool - got you Andrej - will incorporate that next time when I get plotting..

Given the mass of colour plots on Panoply I just picked one that looked cool. So what you see on the images above doesn't have a true zero point reference and may eschew rhe anomalies. Will hopefully work up as time allows.. 🙂

As an aside do u know when Copernicus seasonal anomalies update each month, I know the season is out for ecm - just wondered if there is a date each month the seasonal pressure level data is released. would be good to see the strat lead from those..

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I think it should be around 10-12th, and similar for UKMO

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