Couple of things - only ways I’m looking at it generally - not specific answers as such -haven’t really thought about role of Hcell or the teleconnections to the troposphere much.

Highest concentrations of 03 in the SH collar region just outside the PSV(PolarStratosphericVortex) are roughly in the quadrant mentioned. As polar night retreats hydrostatic balance requires anti-cyclonic development following any warming.

Perhaps it can be argued that there was a slight shift westward from the area of highest frequency of blocking in the SH, towards 90E -180 in September.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/blocking/real_time_sh/real_time_index_nrm.shtml

I visualise blocking as an important component in planetary wave driving which may be guided into the interior of the PSV and cause it to weaken as seems to have happened this year.

The PSV rotates on its axis it seems independently from the parameter fields(and the anti-cyclone) in the collar region.

But at other times, the cells in the collar region suddenly begins to circle in concert with the PSV’s rotation - that part at least might describe in some mechanical way, the eastward migration of these cells -they usually decay over mid-pacific at the earlier stage,rather than coalesce into a single intense high cell prior to the initiation of the final warming.

Looks to me like the final warming is not far off?

What do the more knowledgeable posters think?

Zonal winds at 60s look set drop well below normal!




Big warm up coming in the strat if GFS is correct!