chionomaniac

I have to say that I gave up a long time ago in looking for specifics wrt to run by run model differences. With these type of Synoptics the main thing to look for is getting the blocking in place. Without this, anything other than transient cold is unlikely. So, block block block is the main thing. If this doesn’t lead to deep cold then we will be unlucky, but longer lasting deep cold depends upon this. Don’t be looking at short term just yet. I repeat from Earlier, a tropospheric modelled early Greenland block from tropospheric wave patterns is the true nirvana of possible cold in mid latitudes. Not Guaranteed. But not the wheel of fortune that a downwelling SSW provides. So if we have a Greenland block on all or most of the outputs relax. If we don’t then fret. History suggests that cold will flood south once we get a true block, so….. Block, Block, Block…..

To be fair, I don’t think enough is known about water vapour entering the Strat from volcanic eruptions in the SH to be sure of NH Strat responses alongside all the other factors. Would welcome a link to research papers that have enough cases and up to date data that have studied this.

Regarding SSW, there are hints at the end of the runs of a wave 1 type pattern developing in the upper strat, so this needs watching for the end of December

This type of pattern verifies far better than a downwelling riskier SSW. Yes deep cold is always a lottery for this country, but an upwelling Greenland split are definitely the tickets I would want to have......

Its a big pity that the berlin site is down. Especially as we are entering such an interesting strat period right now. So those of you who were around in 2010 will remember the upwelling splits that appeared in the lower strat which originated from (internal) trop wave based breaks, And now we are seeing the same type of pattern all over again with record low u winds at the 100-70hPa level. u60n_100_2022_merra2.pdfu60n_100_2022_merra2.pdf u60n_70_2022_merra2.pdfu60n_70_2022_merra2.pdf This is at a complete contrast to what is occurring in the upper strat . Here the SPV remains at normal strength and highlights the disconnect between upper and lower strat. Long may this continue u60n_10_2022_merra2.pdfu60n_10_2022_merra2.pdf I have a fair bit of disinformation over on twitter about the possibility of a SSW on the cards - but it is mportant to pointout that internal wave break and split vortex has a completely dynamic process than a baroclinic collapse of the vortex brought about by the later season MT led wave breaks in which the SPV collapses from top to bottom - A far riskier way of acheiving Mid latitude cold. So all in all a terrific propect for the start of winter with a risk of rinse and repeat throughout December before the possibilty of a SSW grows towards the New Year. 2010 was a terific start to winter and I suspect 2022 will be as well. The trend is our friend, so I wont be looking at interrun differences with too much concern as long as the pattern stays the same. Data Services ACD-EXT.GSFC.NASA.GOV Available annual Meteorological data PS if the merra charts dont come up use this site and look at mean zonal wind at 60N for all levels

Just scroll into the map. It’s insane the number of power cuts at the hottest part of the day.

And so the fallout of the hot spell starts. At home following a heat induced migraine and the leccy has just got cut. Looking at the uk power network I am far from alone Live Power Cut Map: Information & Updates | UK Power Networks WWW.UKPOWERNETWORKS.CO.UK Live power cut map for London, East Anglia and South East England

Supercell from yesterday. Five tornados bagged

Thats quite a nice chart on thr GFS at T+114. Oozes potential

Hey Nick, What a well researched, clearly explained, detailed forecast that both seasoned aficionados and newcomers can understand in equal fashion. A difficult task in removing complex jargon but still completing a forecast that all ends of the spectrum can comprehend. No mean feat. And furthermore I can’t disagree with your overall direction looks good to me and I know how difficult this is to produce. So a big thank you and even bigger good luck. I hope that you are far more successful than me!!!

or here https://www.cpc.ncep.noaa.gov/products/stratosphere/sbuv2to/archive/nh/

HI C - I don't know how long you have got but historical ozone records can be found here https://www.cpc.ncep.noaa.gov/products/stratosphere/omps/archive/nh/

Went on a little night time lightning storm chase with the main chase man and friends last night. Managed to get lots of pics of lightning And here are a few looking south from Goodwood.

A big reason for less accuracy is the lack of strat polar vortex in the summer. This is replaced by weak negative u winds in mid strat which turn positive the lower that one descends. Strong positive strat u winds in winter give a very reliable indicator of trop conditions at medium range. Probably the most reliable winter teleconnection. Anyway, is Svalbard on a red or Amber list, because looking at the ECM 850’s at day 10 this could be a lovely spot for a warm holiday!

Me neither, but have come to expect it over time. Still a few more opportunities over time, and an excellent shelf cloud observed over Dungeness

Nice back building occurring behind main band. And a little further west too.......

Lol. There are far better roads around there to use!

Lol. The surface based storms all died. The storms from France earlier are giving me the usual miserable rain from the forward spreading anvil. New elevated storms are forming on the eastern side of the french dross and these have initiated because of the mid level destabilisation moving north, not because of the French storms. In fact, it is quite obvious that the fallout from the surface french storms have actually interfered with anything elevated forming further west.

First signs of cells actually developing in the Channel now so upper destabilising starting to occur

The initiation of the elevated storms is quite different from the initiation of the surface based ones over the channel. Otherwise every surface based storm leaving northern France would reach us still active as an elevated storm. And down here we all know that doesn’t happen.

I think it is a case of ignoring the surface based storms over northern France atm. Our storms will come from the higher instability aloft later on

Just seen a dp of 18°C over at headcorn aerodrome on xc. That’s pretty juicy for the UK. Especially as I looked at the RH at various levels for this evening and there will be a lot of moisture up there

What a fascinating read, Brick. Thank you for going to the effort of writing about this. I will keep an eye on this area for activity on my earthquake apps.

Lol. Winter ends in a week. Wouldn’t rule out spring cold shots though

Looks like there are no ice sculptured solutions in the offing in the foreseeable looking at the models. What a difference from earlier in the winter when there were plenty, despite some saying it was a cold biased narrow minded view. Lol. It wasn’t- just a realistic assessment of what was on offer. Just as now is. Back to the norm.