Model Output Discussion - Snow for some, but what else is in store?

[Jason M]

11 minutes ago, Cold Winter Night said:

Curious about this, I ran it through NOAA's HYSPLIT model for a central UK location (using the available  GFS 6Z output) and found this:

On Thursday the 21st:
- Air at 10m asl would come from Taimyr Russia, through Greenland and Iceland.
- Air at 500m asl would come from the central Atlantic looping through the Norwegian Sea.
- Air at 1500m asl would come from Labrador, doing that same looping.

On Friday the 22nd:
- Air at 10m asl would come from Taimyr Russia, through the Barents Sea.
- Air at 500m asl would come all the way from the Bering Street, doing a tour along the Russian Arctic coastline and the Barents Sea.
- Air at 1500m asl would come from Ireland, moving through Greenland and back.

What a brilliant post. Would have been really interesting to see what the sources were for the last 'so called' cold spell.

[Battleground Snow]

Control and mean at 204,

It does feel a bit like we are going round in circles at the moment, but the more chances we get the more likely it's going to land at some point?

Graph form heading to -6

[Cuban Zebra]

34 minutes ago, Winter Hill said:

Those snow charts are Load of old tosh.

I’d say it got it pretty much bang on today!!

[Ice Day]

So just when you're ready to have a few days off, the models drag you back in again. Generally, decent 12z's. The Control looking great at 216. The mean is an improvement as well!

 

[Garthvader]

Last few runs seem to have legs....pun intended

[Man With Beard]

My eyes are at T120, and the trough coming off Newfoundland

That's a little close for comfort. It's currently negatively tilted, encouraging sufficient build of heights to allow a northerly. But the ridge ahead of it is small. Any smaller, and the trough may go over rather than under, and the ridge will collapse. I think? Hopefully the SSW will do something magical and prevent the collapse!

[Frosty.]

Although the Gfs 12z op (hopefully loses the plot towards the end)...for sure there is quite a lot of wintry potential before that!..and we are entering an extremely volatile phase so basically all bets are off..I’m actually looking forward to the rollercoaster ride during the next few weeks!

[Battleground Snow]

That's a strong singal at 252 for a ton of Arctic blocking like advertised on the OP.

The ensembles are chopping and changing almost as the OPS at the moment, but it's the best tool we currently have for long term.

 

Edited January 14, 2021 by Battleground Snow

[feb1991blizzard]

GEFS are a massive upgrade, loads more members plummeting and for longer too.

[Ice Day]

I would say this is a surprisingly strong signal as a mean at 252.

 

[Ice Day]

2 minutes ago, Battleground Snow said:

That's a strong singal at 252 for a ton on Arctic blocking like advertised on the OP.

The ensembles are chopping and changing almost as the OPS at the moment, but it's the best tool we currently have for long term.

 

You beat me to it again!!!!!

[Phil Blake]

2 minutes ago, feb1991blizzard said:

GEFS are a massive upgrade, loads more members plummeting and for longer too.

-5 mean for London. Looking good. Should be colder up north

[Battleground Snow]

Just now, Ice Day said:

You beat me to it again!!!!!

Haha, Feb was too fast with the graph form.

Good to see a cold cluster that far out!

[beefy201]

3 minutes ago, feb1991blizzard said:

GEFS are a massive upgrade, loads more members plummeting and for longer too.

I think that resembles our heart rates at the moment giving the current set up lol 

[Met4Cast]

3 hours ago, mb018538 said:

@Met4Cast we must be looking at different ensembles? Just had a look out to 360 and I can’t see any promoting scandi blocking at all. Just looks like stronger heights persisting to the N/NW forcing a southerly tracking jet with low pressure headed our way.

Apologises, I mean to say Greenland blocking rather than Scandi blocking. 

Sizeable shift in todays GEFS mean towards a stronger Greenland block, as @Catacol mentioned either earlier or yesterday, models will now be starting to factor in the SSW in real time & will be able to begin modelling that into the trop patterns we see appearing. This run is evidence of that in quite a large shift towards an Arctic high in the mid-term.

I would expect the Det runs to go wild over the coming days, we'll probably see runs showing very mild almost spring like weather across the UK only for a BFTE style cold spell to appear on the next. 

Those of us who have been following the means these past few days have had a much more relaxed time of it, my advice for those of a nervous disposition would be to ignore the Det runs entirely beyond 120, and focus purely on the mean charts.

[MattStoke]

8 minutes ago, feb1991blizzard said:

GEFS are a massive upgrade, loads more members plummeting and for longer too.

There’s the signal for more significant cold from around the 21st again. It’s almost as if people shouldn’t get hung up on every model run

[Battleground Snow]

Maybe the chart of the day for south east members... Mean dew points go below 0 after the 21st

 

[Tim Bland]

Looks like we are back to (a slightly weaker version of) where were a few days ago. Cold enough for snow after the 20th - These are for the south / London 

[Youcan'tbecirrus]

23 minutes ago, Man Without Beard said:

My eyes are at T120, and the trough coming off Newfoundland

That's a little close for comfort. It's currently negatively tilted, encouraging sufficient build of heights to allow a northerly. But the ridge ahead of it is small. Any smaller, and the trough may go over rather than under, and the ridge will collapse. I think? Hopefully the SSW will do something magical and prevent the collapse!

What difference would the high shown over Greenland make ? To my very untrained eye that look very different so I suspect whichever is right would affect the evolution ?  

[Vikos]

1 hour ago, SLEETY said:

Siberian high about to make an entrance? Finally,we are getting SSW effect.

Was there ever a doubt about it? ?

as I mentioned in the Morning, we See a Swing-back. But there will be more Swings to come, so lean back and don’t take every run as done...

Edited January 14, 2021 by Vikos

[Anthony Burden]

Not a bad GFS 12z run the Greenland high as I have said before is crucial needs to strengthen 

and expand to push the low pressure further east.Later as Met office 30 day tells the story 

low pressure diving south but crossing southern England.Good for the north but not south

need them a couple of hundred miles further south which a strengthening of high pressure 

would accommodate this,fingers crossed could still happen.

[stratty]

Good to great charts so far this evening, hope all are well!  

[Youcan'tbecirrus]

4 minutes ago, Youcan'tbecirrus said:

What difference would the high shown over Greenland make ? To my very untrained eye that look very different so I suspect whichever is right would affect the evolution ?  

There were two images shown on MWB's post.

[Paul_1978]

Just for some context, we’ve had 2-3 inches of snow here in low lying Wakefield today, and the scene is repeated across much of Scotland and the spine of England - and this is the chart. You wouldn’t have thought it would you? By which I mean, you don’t need pretty charts for a brilliant snowy outcome as we’ve had today.

Edited January 14, 2021 by Paul_1978

[Snowjokes92]

Some momentum building in the models again, something is happening. Small tweeks in the short frame could throw something really good up for us I think.