The Australian Weather Forum

crikey wrote: ↑Fri Aug 23, 2019 1:27 pm
I can see the temp' gradient you posted above for the 10hPa showing -78 on the cool side and - 8 on the warm side.
That gives a gradient hill of about 70deg c Is that what you are saying?

Polar vortex at 10 hPa is normally between -60c to -80c in August (you can see that in this attached shot). Latest EC is showing a large area over the South Pole above +0c including 4c. These are anomalies like I have never seen before on any chart.

Didjman wrote: ↑Fri Aug 23, 2019 2:39 pm As I mentioned in a post here the other day, this could coincide with a projected strong MJO. What then........?

I'm keeping any eye on that one Also watching the easterlies in the tropical pacific. If moisture becomes involved with any polar vortex surge from a SSW, it will go atomic in the southern Hem.

Hence my question JS. Thx to your sharing of knowledge, I am starting to get a handle on things

JasmineStorm wrote: ↑Fri Aug 23, 2019 5:50 pm

crikey wrote: ↑Fri Aug 23, 2019 1:27 pm
I can see the temp' gradient you posted above for the 10hPa showing -78 on the cool side and - 8 on the warm side.
That gives a gradient hill of about 70deg c Is that what you are saying?

Polar vortex at 10 hPa is normally between -60c to -80c in August (you can see that in this attached shot). Latest EC is showing a large area over the South Pole above +0c including 4c. These are anomalies like I have never seen before on any chart.

Is that chart / charts freely available?? If so I would like a link to bookmark for future reference please

Didjman wrote: ↑Fri Aug 23, 2019 6:19 pm

JasmineStorm wrote: ↑Fri Aug 23, 2019 5:50 pm

crikey wrote: ↑Fri Aug 23, 2019 1:27 pm
I can see the temp' gradient you posted above for the 10hPa showing -78 on the cool side and - 8 on the warm side.
That gives a gradient hill of about 70deg c Is that what you are saying?

Polar vortex at 10 hPa is normally between -60c to -80c in August (you can see that in this attached shot). Latest EC is showing a large area over the South Pole above +0c including 4c. These are anomalies like I have never seen before on any chart.

Is that chart / charts freely available?? If so I would like a link to bookmark for future reference please

Sorry sir, it is paywalled. So you would need to join up

JasmineStorm wrote: ↑Fri Aug 23, 2019 6:29 pm
Sorry sir, it is paywalled. So you would need to join up

JS, I sent you a PM

There is something strange going on at 10 Hpa. At 70Hpa, the 3 elongated vortices have air moving clockwise into them. At 10Hpa the winds are still clockwise but spiralling outwards like the top of a cyclone.

https://earth.nullschool.net/#current/w ... 91.86,1379
https://earth.nullschool.net/#current/w ... 91.86,2319

Also: https://wordpress.com/block-editor/post ... ress.com/4
for daily updates on the Eddy Heat Flux Anomaly sequence

Didjman wrote: ↑Sat Aug 24, 2019 7:21 am There is something strange going on at 10 Hpa. At 70Hpa, the 3 elongated vortices have air moving clockwise into them. At 10Hpa the winds are still clockwise but spiralling outwards like the top of a cyclone.

https://earth.nullschool.net/#current/w ... 91.86,1379
https://earth.nullschool.net/#current/w ... 91.86,2319

Also: https://wordpress.com/block-editor/post ... ress.com/4
for daily updates on the Eddy Heat Flux Anomaly sequence

I think that you will find if you zoom out you will see high pressure circulations on either side of the 10hPa layer.
The wind streams leaving the perimeter are feeding in to these anti clockwise rotations.
During the the 2002 split,this was the case.Anti cyclones on either side of the central vortex.
However l have no idea if that arrangement is a common seasonal event.

The AAO seems to be responding to the stratosphere temperature anomalies by remaining negative since July 4th 2019 and is forecasting another significant drop in the AAO this coming week into the first week of September.
That is now 51 days in the negative range
Might have to keep watching the stratosphere temp' anomalies , they seem to be highly correlated with the AAO with minimal time delay in response.
I might put that in my observation routine in the future


https://www.cpc.ncep.noaa.gov/products/ ... /aao.shtml

Jetstream report.24th August 2019
The southern hemisphere jetstream pattern has changed from zonal sub tropical and weak sub polar in the winter of 2019 to a moderate meridonal wavy pattern for both jets. The sub polar jet still looks a bit weak



http://www.bom.gov.au/australia/charts/ ... fresh+View

We almost have a split at 10hpa:
https://earth.nullschool.net/#current/w ... 96.80,1379

According to GFS modelling, the forecast ave temp anomalies from 01/09 are +25 Celsius from heights of 5 down to 50Hpa. This is for the stratosphere 60-90 degrees South. See the link to the graphic on my blog below:

https://didjman59.files.wordpress.com/2 ... 085118.jpg

Didjman wrote: ↑Sat Aug 24, 2019 7:21 pm We almost have a split at 10hpa:
https://earth.nullschool.net/#current/w ... 96.80,1379

I can't see anything that resembles a split? atm

Thanks for the temp' anomalies for polar stratosphere. That certainly looks intriguing.

crikey wrote: ↑Sun Aug 25, 2019 9:21 am

Didjman wrote: ↑Sat Aug 24, 2019 7:21 pm We almost have a split at 10hpa:
https://earth.nullschool.net/#current/w ... 96.80,1379

I can't see anything that resembles a split? atm

Thanks for the temp' anomalies for polar stratosphere. That certainly looks intriguing.

Re split, it didn't last long The vortex at 70hpa is under alot of stress! No surprise there

The MJO still looks to be strong in our neck of the woods between Sept 7 - 11.

At 70hpa, back to 1 vortex, at 10 hpa back to an outward spiralling vortex(1600 local):
https://earth.nullschool.net/#current/w ... 91.29,1950
https://earth.nullschool.net/#current/w ... 91.29,1950

Not much change in the vortex at both 70 & 10 hpa. The heat anomaly forecast is still well up for early next month according to gfs.

Heat flux anomalies appear to be cascading while average heat anomalies are still high:
https://wordpress.com/block-editor/post ... ress.com/4

Is EC still forcasting +4c for 10hpa for end of month JS??

Didjman wrote: ↑Mon Aug 26, 2019 1:19 pm
Is EC still forcasting +4c for 10hpa for end of month JS??

Latest EC run (00z) showing a pocket of +6c on Friday. Truly remarkable in recorded history.

JasmineStorm wrote: ↑Mon Aug 26, 2019 5:14 pm

Didjman wrote: ↑Mon Aug 26, 2019 1:19 pm
Is EC still forcasting +4c for 10hpa for end of month JS??

Latest EC run (00z) showing a pocket of +6c on Friday. Truly remarkable in recorded history.

Can you post the graphic please

Latest EC upper Strat temperatures for Friday. +6c bubble inside the +4c contour line over the South Pole

Thx JS What is likely to happen to the vortex from that?? Split in 3??