ghoneym

light rain, light snaw, big slushy snaw, now rain again. can't see us digging ourselves out here in the morning unfortunately

The East Wemyss snow and ice shield is fully operation ?️?️

Cracking day, slight wind, chill factor felt like - 5! Perfect bike riding weather for the little one . Fingers crossed for even a flurry to watch tonight but not convinced it will happen.

Brilliant in depth post, Wonderfull stuff. This is why the Scottish regional forum is the best

Merry Christmas all! Hope you have to all have to tunnel your way out your homes some point soon bring on the snawwwww

Some further discussion regarding the record breaking forecasted drop in temperature in the Stratosphere. (in a very particular area, not to be taken as a large proportion of area) A potential temperature of - 99 still being forecast on the nasa ozone site. A gravity wave off the South tip of Greenland potentially being the culprit for this phenomena.

The Quasi-biennial Oscillation (QBO) ACD-EXT.GSFC.NASA.GOV Plots of the QBO

A few replies to my question re - PSC 2 formation on twitter. Might belong in the model tweet thread, or still relevant here?

Does anyone have an explanation for this? I think PSC 2's in the artic are only formed by ice rather than the chemical reaction in the antarctic. At 30hpa I'm only imagining warming kicking off up there.

I use the nasa ozone website to better visualise what these plots look like. It's a great snapshot that gives you an overall picture of all layers of atmosphere and where anomalies are situated. Once you are on the nasa ozone site click on the tab top right that will say Northern hemisphere. Then click the meteorology tab from the top bar also. You will be taken to a page that looks like the one above. Then scroll down to the bottom of the page and you will see 3 li ks at the bottom of the page, like in the image below. Click on artic forecast maps. You will arrive at a page that looks like this.... You will see the different options from the blue collum on the left. Look for the different hpa charts and select from 1hpa down to 700hpa. Each one has a little + sign on the far right collum. Select that and you will be taken to a page like this... Click the start/stop button and you will see an animated version moving through the forecast. Try and visualise where 30 to 80N would be on the hemisphere and where you see the higher temperature anomalies coming into play in relation to the chart Lorenzo displayed.

Sorry to be a pain in butt...but it looks to me that the mean wind speed for this time of year is 40 m/s and to be up at 60m/s we would be looking at breaking records? I'm not trying to be pedantic or anything but just want to try and understand what I'm looking at from the various different charts available. Wave 1 is on top for now that is for sure.

I hate to admit that the CFS is correct but I think it is right now, make your own mind up....

Arctic High modelling is a problem from what I can see. I'm willing to wait 36-48 hrs until it is actually in position to see what happens. Add poorly plotted MJO forecasts into the mix and we have a clustertruck. Massive changes will happen within 15 days, of that I have no doubt.

I have been pondering the QBO pattern for a few days now and as you say there has been lots of discussion on twitter with regards this years pattern. As a punt could I suggest that Covid 19 has had a bearing on the pattern? Bear with me I'm not a conspiracy theorist....what I remember from the peak pandemic were news reports of much cleaner air globally due to lack of moving traffic, industry shut down, flights grounded etc. Around 40% of Nitrous oxide emissions comes from human activity, (listed above as transport/industry) the N2O is a greenhouse gas that breaks down the ozone layer long term, N20 also absorbs solar radiation however and traps heat in the upper atmosphere, so as a short term effect are wee seeing some kind of feedback mechanism from this as the images above show for a good quarter of the year we had a huge reduction in N20 in the atmosphere, allowing more of the solar radiation to penetrate to the surface, hence the extended wildfires and elevated SST's we are experiencing? Having said all that I'm at a loss as N20 levels in the stratosphere when exposed to sunlight and oxygen transform the gas into Nitrogen Oxides which also damage the Ozone. So again due to the lack of N20 we haven't been damaging the Ozone as much this year. I thought I would have seen this improvement on the NASA total column ozone charts as the year has progressed but currently to no avail. It is possible that the short term effect of lower N20 level have allowed through more solar radiation than the effect of Ozone breakdown which takes considerably longer? My missing link is how this is linked to the QBO pattern, but I have a hunch lol and the theory I'm still working on......

Seasonal MJO cycle at phases 5 & 6 shown for 2 SD's on the RMM plot (MJO strength currently being plotted/forecast less than this). So many other factors at play currently also, so use loosely I would suggest.

The chart was 50mb Geo height?

Are we likely to see a coupling of Strat/Trop? The split does't seem to last and I can see more of a displacement event long term from the 10hpa/30hpa and 70hpa trends. I'm pretty sure we are seeing more of an absorption type event so far this year unlike last season but how that will transform into trop patterns will be a waiting game? There is nothing particularly of interest in regards extremes yet from what I can tell. Heat flux, temperature, 60N wind all pretty mediocre or within the climatological mean? All things currently look driven by trop patterns, particularly influenced by SST's and the poorly plotted MJO influence.

Nice day out walking with little beagle today, big beagle couldn't be arsed so stayed at home. They have started clearing the old railway line from leven to thronton junction as part of a 75m pound investment to rejuvanate the river leven area. Alot of work ahead but good to see it started. Cracking winter weather walking day, flat calm, bright and fresh.

Here is my craziest theory. This year we are seeing a la nina pattern and the thermoclyne looks a tad strange to me, the sea surface temperature anomoly in the 40-60N latitudes in the Pacific are high/warm. Qwith the lack of sea ice in the Arctic, particularly around the bearing Sea, I think the warm waters have had a free run through the bearing sea for quite some time this year and are running down through scandi into the North Sea, hence the warmer SST'S here. Probably garbage but its the best I could come up with ??

The average Max temp for December SST for the forth is 11 degc, as off today we are just shy of 12 degc, may go for a swim later ? not sure a bridge can cause any type of weather phenomena but happy to be proved wrong. More likely to be an effect from the yearly gulf stream perhaps?

I've worked down on one of the jetties on the forth for 15 years now and although squalls / streamers are very common I have not seen the SST this high before at the start of winter, a bit bizzare

Yes! Seen a few flashes out my back door facing East and couple of rumbly bangs, don't think I've experienced that at this time of year before

Great to see such Harmonie in here this evening so far......GFS 12z signal for heights into Greenland dropped on this run, fully expect chop and change on this for a good few days to come. Lots of wintery potential for many areas to come next 48 hours, low lying areas included!

As a conservative property, angular momentum in a closed system has constant total but can be redistributed within that system. For example, the atmosphere transfers angular momentum poleward in both hemispheres principally by means of transient eddies. Poleward transfers of mass however mean decreased axial angular momentum because the mass moves to a smaller radius arm from the Earth's axis of rotation. If there are no interactions with the solid Earth, a Coriolis torque will ensue, acting to increase the zonal winds, and keep the angular momentum constant. The transport of angular momentum is also accomplished vertically, carrying angular momentum as part of the Hadley and other mean meridional circulations.

There have been many winters in the past where West based QBO and La Nina influences have been prominent. Would I be correct in saying these parameters individually tend to bring a milder UK winter but together pose a stronger threat of a SSW and colder than average UK winter? I did have a look at the composites a few weeks back but never saved any at the time as It was a nosey out of curiosity