SMU

Add to the above 4 out of the 50 ECM ensembles have maxima at 0c or below for debilt at day 15 Thats nearly 10% in old money ! Its a start

Lol blizzard here at greenhithe Settling at the top of bean 75m

Hammering it down with snow here

Snowflakes 4m ASL Greenhithe

Mucka if you took UKMO at face value im not 100% sure it would be overrun- Looks like a bit of disruption there- possibly enough to force an undercut- S

Morning all Awsome ECM today - I think It was mentioned about the low cutting across the pole for reload GFS out to 114... Building the canadian ridge northwards same as ECM Reload is coming

Todays have firmed up the detail around the Northerly - It 'feels' the landing zone for the 850s are -9 for scotland with widespread -7 in england, with the odd pocket of -6 mixing in. There is then a lull as we have some energy moving south again from the North - That could be North south from up out west of Norway or it could be a little flatter - NW > SE out of iceland.. Post that at face value things look quite muddled with pockets of low pressure difficult to pin down however my personal opinion is that we should be cautiously optimistic that pressure remain stable enough to the North / North east of us to repel the atlantic SW towards spain- When looking at the specifics there are 3 models through 192 that are very nice runs- The JMA + GEM + NAVGEM show this scenario whereby the atlantic is gently steered away, THe ECM is a tad more energised at 192-216 however its only fractions of changes required to bring the cold modelled back further west. Chart of the day is the JMA 180 as is shows a very cold Eastery flow - I watch with interest at further runs- As said a few times now, this could be a cold spell not snap- scotland looks at 4 days already & if we get that continental flow we quickly could get to 5-6 days for England.... S

As mentioned earlier ECM filling the void of the atlantic full of ridging at 216.... Could be interesting this at 240! S

Just before the ECM fires up its worth noting that the post 168 the GFS / GEFS & ECM arent really showing much signs of forecasting the jet to increase - there must be a significant disconnect between the strat zonal wind - running at peak velocity V the mean & the trop vortex... This is resulting in a large void of +VE height remaining in the atlantic as we head towards FI - This will preclude lots of exciting runs for cold- Im not saying its odds on, however this could be a cold spell rather than a cold snap - with a whiff of pressure rises over greenland & scandi theres all to play for ..... S

Gfs 850s through 120 06z scotland (126 ) was 0- -2c 12z scotland (120 ) is -8 - -10c !!! Upgrades ðŸ˜

I cant any more * there was 2 reasons - 1 was that the 06z + 18z dont have the same amount of upper air data as the other 2 * but the main one was ( you have to just trust me on this one - the old model performance statistics page had the x4 GFS runs but RMS score at day 5 & 6 divided up into areas It was sbout 7 or 8 * SHem * Arctic * Atlantic * Russia * States * asia * Africa & maybe one or 2 others I reviewed the arctic scores daily over 2-3 years & the 06z & 18z always scored very poor on the arctic area... Hence my distain for these 2 runs in particular the 06z Best Steve ( yes PM the same)

So as we start the engines on yet another 12z run I fully expect to see the UK upgrade to the full potential of the 850's in the northerly Thats touching -10 for scotland & -7/-8 for the south - Remember the 06z + 18z never get the polar heights as good as the 12 & 00z's So as a result they are generally just slightly less amplified ( esp the 06z) Also with this highly unusual blocking scenario from canada cojoining with an atlantic high - dont expect your run of the mill toppler.... S

Afternoon - So things have settled a little today, the GFS has made the biggest movement in the last 24 hours - significantly increasing the amplitude of the wave over the states so that we get positive heights over greenland- The ECM however has slightly toned down its extreme solution from yesterday with no cut off high - just the initial canadian blocking - So either way the decent convergence still indicates a strong probability of cold weather spreading south in the latter stages of next week - Post that there is still a chance of a significant block over greenland developing- Im pretty sure nearly all of our greenland highs have manifested out of vertical advection & ridging out of the atlantic, not out of a ridging canadian high ( at least not on its own ) However around day 9-11 there is a possibilty of x2 high pressures morphing into 1 as a deep polar low cuts across the pole - If people can remember the second phase of cold - coming in mid dec 10 this came from this scenario An atlantic high meeting a canadian high with a polar low - If someone can care to post 14/15/16 of dec 10 then you will see what I mean .... Cheers S

Indeed good ^^^^ Plus GFS through 96 much slower & advection is more pronounced & vertical - S

Evening All 5 posts in 24 hours - something must be a foot.... The ECM / GEM combo tonight are almost worthy or 'boom' runs - with the ECM at 192 having developed a fully cut off Greenland high- The development of this projected cold spell is unusual in as much as it started out on the ECM at 240 as nothing more than a 24-48 hour toppler & has developed over the last 3 days ( 6 runs ) into something more significant with the main ground work at T120 -144 The only caveat is The GFS is not on board yet ( although playing catch up ) so because of that we have to wait another 24-48 hours .... However onto the upbeat bits - my commentary on this is noone has forecast this - all agencies going with the el nino climatology / analogues which suggest totally the inverse at this early entry point to winter- Chart of the day - With the -6c line getting into central southern england & snow showers in the north / North east. The key chart though is the 120 one with that significant plume of WAA into canada ( having commented on this over the last 36 hours ) This is about as good as it gets !! Have a good eve- S

ECM through day 8 & 9 still very supportive of the aptly named 50:50 low in the states pumping the heights towards greenland This is the first run however that maintains heights long enough to develop a split flow underneath as opposed to flattening out... Could be an ECM wobbler or a genuine upgrade To early to tell....

2 wave pattern.... Ship ahoy rodney.... S

GFS Through 150 slower again & more amplifed in the central canada will mean another little pidgeon step towards the ECM/JMA/GEM solution - S

A decent ECM run this eve - especially if you live in the far North with cold air digging in ... This the pick of the charts The pattern changer - an inland runner low pressure over the states phasing with PV lobe which develops into a huge storm pumping heights around it ( across the Eastern us into the maritimes & the other side over the Northern pacific ) Huge snow amounts for Central southern canada feeding into the midwest - This gives the Uk some confidence that the further Nortth you go we could engage the colder uppers.. Possibilites !!! Lets see where the next 48 hours go S

Early on on the GFS at 114 showing a slower more amplified jet over the states - with slightly better height profiles over eastern canada - may allow for the lows to dig a bit further south on this run.... S

In amongst the doom & gloom of the recent outputs there seems a window of opportunity for some snow over the scottish hills on friday - The ECM touting a chilly westerly flow with 850s around -5c i guess will see the freezing level around 3-400M A few showers blown through on a strong westerly wind.... It wont last long though....

Keep the thread on topic - im enjoying all the posts on here- But ATM the warmth is snubbing any excitement... Remember in this current climate where change is faster than ever before - it would be foolhardy to forecast based on analogues - Im busy with my baby - Enjoy the run up to winter - I will be dropping in from time to time.. Especially if cold is on the horizon ... Cheers S

Evening all - A whiff ( like the old bisto advert ) of something more seasonal in around 9-12 days time with some sort of +VE anomaly in the northern atlantic - maybe even into greenland- A long way off though & the last attempt by The ECM was pretty shocking... Im not bothered by the lack of any cold pre 15th november as it amounts to pretty much nothing anyway So I suppose the opening of winter snow 'availability' starts in 9 days time... Fingers crossed we start seeing some better eye candy nearer that time.... Enjoy S

ECM mean pretty supportive of the OP at 120 I would look for the model suite to swing by end of the 12z tomorrow- S

The ECM & GEM are on the same wavelength as is the JMA all be it a bit flatter ECM 240 shows the first big winter pattern setting up for canada & the central northern states of the US! S