Model Output Discussion - the cold has arrived

[ScottSnow]

11 minutes ago, london-snow said:

I’m in agreement with both statements tbh, let’s be honest most of us that do hibernate through spring summer and autumn are only here during the winter to focus and discuss the possibility of cold and subsequently snow which let us be honest if theirs no snow theirs no point. Granted Matt their will be chances going forward the longer this current spell extends, however those who have called it a 2010 repeat are way wide of the mark. We had early snowfall that stuck around for days before any so called breakdown. Let’s see what happens i like you feel get the cold in place and the games will begin, hopefully sooner rather then later. 

I have seen a few on here mention this spell being similar to 2010. Nov/Dec 2010 was historic with Dec ending up one of the coldest of the past 100 years. This spell was never going to get to that standard IMO, although I have snow outside now and there should be more opportunities over the next week. It could still be a notable spell similar to Jan 13.
The models aren’t showing the depth of cold that we had in 2010.

Edited December 8, 2022 by ScottSnow

[Howie]

10 minutes ago, irish1 said:

Track of storm firmly South now, chances of frontal snow look to have faded away but will help keep the cold locked in.

Greenland block said "computer says no"

[Ali1977]

A little feature has actually cropped up in central southern England on Sunday, I’m sure it’ll be gone by the next run but it’s something to look for.

[tight isobar]

Detached micro energy looks interesting Sunday/ Monday snow showers could crop up almost anywhere!!. Something else to keep note of!

[bluearmy]

4 minutes ago, Ali1977 said:

A little feature has actually cropped up in central southern England on Sunday, I’m sure it’ll be gone by the next run but it’s something to look for.

Ec op had a some snowfall in se england on Sunday 

At this range, it’s impossible to rely on any output for Sunday - but it’s something to watch and it shows that surprises are possible 

[tight isobar]

Now then this is what I’m talking about- as the lp gets block bound elongation begins- a classic clue to sliding under- and will confuse the track unti 24hrs inbound to where it’s wants to make landful- far from deciphering yet!!

[tight isobar]

2 minutes ago, Ali1977 said:

Interesting graphics on latest bbc forecast - best case scenario really with a spell of snow in the south later next week then a return to cold!!

Those graphics basically highlight my thinking-@ engagement- then revert...if we do get the nudge- there will be some impressive ground accumulation midlands southward!!!

Edited December 8, 2022 by tight isobar

[syed2878]

Just been looking at NOAA 6-1 and 8-14 days discussions and forecasters over there going 40% of this afternoons gfs for the USA AND 60% OF ECMWF 0H RUNS I don't know what it would mean for us here though.  

The official 8-14 day 500-hPa height blend consists of: 40% of Today's  
operational 12z GFS centered on Day 11, and 60% of Today's 0z European Ensemble  
Mean centered on Day 11  
 
 
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: Above Average, 4 out of 5, due to  
good agreement among the dynamical and statistical tools over Alaska and the  
western CONUS, offset by some disagreements in the eastern U.S.

https://www.cpc.ncep.noaa.gov/products/predictions/610day/fxus06.html

[Rain All Night]

A new GFS has reached T120 without anybody posting it!

Edit: Sorry @tight isobar and @Ali1977, I somehow didn't realise that's what your recent image posts are from 

Edited December 8, 2022 by RainAllNight

[tight isobar]

My punt- nxt week will be a snowy 1- with most involved, things ramping up now....classic classic pop up feature notions...

[bluearmy]

5 minutes ago, syed2878 said:

Just been looking at NOAA 6-1 and 8-14 days discussions and forecasters over there going 40% of this afternoons gfs for the USA AND 60% OF ECMWF 0H RUNS I don't know what it would mean for us here though.  

The official 8-14 day 500-hPa height blend consists of: 40% of Today's  
operational 12z GFS centered on Day 11, and 60% of Today's 0z European Ensemble  
Mean centered on Day 11  
 
 
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: Above Average, 4 out of 5, due to  
good agreement among the dynamical and statistical tools over Alaska and the  
western CONUS, offset by some disagreements in the eastern U.S.

https://www.cpc.ncep.noaa.gov/products/predictions/610day/fxus06.html

Well we shouldn’t necessarily be excited that noaa think the gfs 12z op for day 11 is a good representation of where they think upstream will be … mind you, upstream with the big block across the hemisphere looks good - it’s was downstream in our sector that didn’t 

[Snowmadsam]

8 minutes ago, Ali1977 said:

Interesting graphics on latest bbc forecast - best case scenario really with a spell of snow in the south later next week then a return to cold!!
Thurs through to Sat below 

I wouldn't take these graphics so seriously. Especially when showing SLP charts as resolution is lower. Precipitation is there as a guide on not a guarantee. Will very depend how conditions are on the ground.

ECM op looked tasty didn't it, however!!

[markw2680]

2 minutes ago, tight isobar said:

My punt- nxt week will be a snowy 1- with most involved, things ramping up now....classic classic pop up feature notions...

I really hope your right, think all we need is a bit of a tilt to the flow either nw or ne rather than straight north, that should encourage showers to push inland

[Snowmadsam]

4 minutes ago, tight isobar said:

My punt- nxt week will be a snowy 1- with most involved, things ramping up now....classic classic pop up feature notions...

agreed. Surprises almost anywhere. Everyone will AT LEAST experience something frozen falling from the sky. 

[TSNWK]

Anyone else watching the movement of purple vortex blob to our north east from around 144 

[Cleeve Hill]

32 minutes ago, irish1 said:

Track of storm firmly South now, chances of frontal snow look to have faded away but will help keep the cold locked in.

Yes. If you following these storms during the hurricane season in the Caribbean, it is always the High Pressure ridges which direct the storms. The strength of the -NAO is steering this one South. 

[ICE COLD]

T168 the uppers are pretty impressive. 

[Lampostwatcher]

Gfs 18z looks definitely more snowy from sunday onwards and very cold 

❄🌨

[NewEra21]

1 minute ago, TSNWK said:

Anyone else watching the movement of purple vortex blob to our north east from around 144 

Closer look, it looks like some alien trying to suck the UK into it's midst

[Howie]

3 minutes ago, Cleeve Hill said:

Yes. If you following these storms during the hurricane season in the Caribbean, it is always the High Pressure ridges which direct the storms. The strength of the -NAO is steering this one South. 

Yep they never steer themselves, if a ridge collapses they just stall like Hurricane Dorian did. This was never going north like models had it previously 

 

Also think we have to give kudos to the GEM for spotting the vortex profile days ago

Edited December 8, 2022 by Howie

[MATTWOLVES 3]

Quite a few now saying boring cold spell after couple of days with no snow! Bit like being being a couple of days into an Heatwave and saying...yeh but still no sun! 

Here's ya little snow blob for Central/Southern parts on Sunday...also perhaps some to look out for in the SE....but unless our Southern members gets snow very soon I'm afraid this cold snap will go down in history as the biggest fail ever...(according to them) you know what I'm saying

Further into next week perhaps more of a surge from the North with those snow showers and down the North Sea.. just micro adjustments with that wind speed and direction and many areas could see some!

In the shorter term enjoy the fantastic glaze of the ice and Frost all over the land the next few days. And remember to top up your anti freeze...dont get putting screen wash in like me...️

[Eagle Eye]

1 minute ago, Howie said:

Yep they never steer themselves, if a ridge collapses they just stall like Hurricane Dorian did. This was never going north like models had it previously 

Not necessarily true, depends on the phase the 'Hurricane' is in. For example, a Hurricane with a strengthening tail will follow the upper level flow hence Hurricane Fiona took a more westerly track than initially forecast because that was where the upper-level flow took it. So it really depends on what phase it's in but as a general rule of thumb I'd suggest that you're correct here.

[January Snowstorm]

Plenty snow reports across Dublin this evening from just a small rash of showers! Great charts this evening but I will always worry when I see heights so weak to our North

[Kasim Awan]

Possibility of big accumulations tomorrow night in parts of low lying NW England as an onshore wind develops streamer activity heading into a cold surface layer.

 

[The Enforcer]

As of 22:20 there is the first significant incursion of precipitation into mainland England (Yorkshire/Nottinghamshire/Derbyshire):

What did the hi-res short-range models predict?

NMM T+10 - underplayed:

UKMO T+10 - non-existent:

Arpege T+10 - skirts the coast:

ICON T+4 - underplayed:

Conclusion: it doesn't matter if the models suggest it is going to remain dry.