Model Output Discussion - Into Winter

[northwestsnow]

What a wonderful week of winter weather ,frosts a plenty and some snow too

onto the NWP 

Patience might be the watchword looking at the 00z runs.

all eyes on the MJO

Edited December 3, 2023 by northwestsnow

[Catacol]

At the point where upstream forcing will begin to re engage the EPS is on the same page as the GEFS, the U.K. trough slightly more resilient than GEFS had it. Same strengthening of heights to the north. 
 

I hope folk can enjoy the week ahead despite the tendency for mild to win out and snow turn to rain across most of the country in time. Plenty of model eye candy won’t be far behind the breakdown…

Edited December 3, 2023 by Catacol

[northwestsnow]

1 minute ago, Catacol said:

At the point where upstream forcing will begin to re engage the EPS is on the same page as the GEFS, the U.K. trough slightly more resilient than GEFS had it. Same strengthening of heights to the north. 
 

I hope folk can enjoy the week ahead despite the tendency for mild to win out and snow turn to rain across most of the country in time. Plenty of model eye candy won’t be far behind the breakdown…l

Bloody azores high trying to ruin things 

[Bricriu]

3 hours ago, Nick123 said:

So confused. 4 posts one after the other. 2 says good start to the day, 2 say poor!! 

If you are looking at the bigger picture it's a great start to the today.  If you are looking at the medium term outlook,  and hoping for cold to come back quickly,  it's not a great start to the day. The few  dry days we had could  soon be cancelled  out by slow moving systems  that decay close by 

Edited December 3, 2023 by Bricriu

[Paul_1978]

3 hours ago, nick sussex said:

Not the best of starts to the day for coldies .

Although some differences remain between the models . The ECM probably the best upto day 6 in that some tweaks could see colder conditions hang on for more of the UK . Day 10 scrapes some interest .

The GFS tries to develop a more northerly flow later but low pressure remains parked over the UK slowly filling . Heights building into southern Greenland are poorly orientated . The pattern needs a large se correction .

The UKMO nothing to write home about !

Earlier two chances for snow . 

The low moving in from the sw . Detail wise still some disagreements , more likely Wales n England , north Midlands towards the ne .

A chance also that as the low clears east there could be some rain to snow for some other areas .

Later Wednesday still some uncertainty as to how the next low moves in . This would in any case be likely to be a snow to rain event for the risk areas .

 

To be fair Nick, after tomorrow I think I pretty much everyone has accepted return to less cold conditions and a wet week ahead. I think we’re all looking to mid month now for signs of a change back to cold, and at that timescale the models will vary wildly. So for me, it’s a case of enjoy the next 48 hours, accept the rainy week, and keep a watching brief on developments towards the middle of December. 

[DIS1970]

Forget the cold/snow hunting for now, nothing is going to stop this current Atlantic onslaught.

[That ECM]

Some consistency from gfs.

[IDO]

That block to the east, if it does not retrogress westwards, usually means the UK is at the end of the Atlantic train. Models are firming up on the Siberian/Russian high staying firm and a UK trough for at least a week (GFS) from D3-4. With the jet near the south, we are on the cooler side. D1-D8 GFS showing this:

So medium term is sorted. Longer term it is less certain as to how the UK trough is broken. Maybe something in mid-Dec, as the trough is attacked by the Russian high and the Atlantic ridge?

Edited December 3, 2023 by IDO

[Chesil View]

25 minutes ago, northwestsnow said:

What a wonderful week of winter weather ,frosts a plenty and some snow too

onto the NWP 

Patience might be the watchword looking at the 00z runs.

all eyes on the MJO

We know the breakdown is coming. It's already here on the south coast. 

We already know the next round of amplification is is coming around mid Dec onwards.

So probably time to take a break from picking the bones out of every model run for a few days and allow the next round of amplification to feed into the extended nwp. Gfs first for obvious reasons.

Then we can start the next showcase in time for Xmas.

Edited December 3, 2023 by Chesil View

[Lukesluckybunch]

Very west based at 240..all the cold air being forced into the atlantic..Euro heights need to clear off!

[DIS1970]

Breakdown is already here, rain has started falling - unless you're 500m + up on a hill/small mountain.

[nick sussex]

The Siberian high needs to do one if it’s just going to block low pressure from clearing the UK .

Another GFS run with low pressure filling over the UK . Cold air to the north trapped there .

[swfc]

10 minutes ago, Chesil View said:

We know the breakdown is coming. It's already here on the south coast. 

We already know the next round of amplification is is coming around mid Dec onwards.

So probably time to take a break from picking the bones out of every model run for a few days and allow the next round of amplification to feed into the extended nwp. Gfs first for obvious reasons.

Then we can start the next showcase in time for Xmas.

Tbh Nws was making a point about going forward, not really picking any bones.

[Vikos]

PV? Where are you?

 

[Lukesluckybunch]

2 minutes ago, Vikos said:

PV? Where are you?

 

Problem is no cold air too tap into now from the east..due to that Siberian high as Nick was saying.the trend is good though,with heights building toward greenland..so a few tweaks come the 12z..and it could be a better outcome

[ribster]

21 minutes ago, DIS1970 said:

Forget the cold/snow hunting for now, nothing is going to stop this current Atlantic onslaught.

Onslaught? Looks fairly average to me...

[SLEETY]

17 minutes ago, DIS1970 said:

Forget the cold/snow hunting for now, nothing is going to stop this current Atlantic onslaught.

Exactly seen it countless times the past 30 years once the Atlantic takes control it can be weeks before things change again.

Heard it all before about background signals look good for bitter cold to hit uk later on,but 90% the time it never happens.

Met got it spot on for once from last Wed about Atlantic winning out.

[BartyHater]

On the face of it the 180hrs chart from the GFS06 appears primed to deliver the Artic goodies, as soon as what looks like the last Low on the train exits stage east… but unfortunately the much vaunted Russian/Kazak High is likely to go from being our potential cold weather friend into enemy No1, by effectively trapping the trough smack bang over the UK going into week 3 of December…IF of course GFS turns out to be right with this trend it's toying with.

 

Edited December 3, 2023 by BartyHater

[Downburst]

Mid December and looking at the ECM 500 hpa anomaly, seems to me there’s a chance of  blocking to the north west or north east. Plenty of interesting options.

 

+NAO at 30% chance during this time, or glass half full way of expressing this is 70% chance of something else.

Edited December 3, 2023 by Downburst

[MATTWOLVES 3]

Disappointed with snow amounts here...I've seen more dandruff tbh

But as long as some of my fellow chasers got a decent amount I ain't bothered. The risk continues for some over the next couple of days before milder air makes inroads....yes it spells the end for this cold snap.......but we've had our 1st cold spell and snow for some so early in the season.

And yes the current drivers that are heading favourable with mjo and increased pressure being placed on the strat look gr8. So perhaps focus on that just before Xmas period of further blocking building momentum..If a pv split were to occur late December early January...we would again be in a position  of wintry goods providing the dice fall correctly.

So those who have snow enjo it..those who don't hold ya patience...as we could be in a much better position 2 or 3 weeks from now. Also plenty of the long range ens hinting at change.

Have a gr8 day...dont be putting a snowball through ya neighbours window and don't be breaking any bones.. 

[swfc]

7 minutes ago, Lukesluckybunch said:

Problem is no cold air too tap into now from the east..due to that Siberian high as Nick was saying.the trend is good though,with heights building toward greenland..so a few tweaks come the 12z..and it could be a better outcome

Just a variation of the same "hopefully" same theme going forward. Seen many worse nhp

[feb1991blizzard]

13 minutes ago, nick sussex said:

The Siberian high needs to do one if it’s just going to block low pressure from clearing the UK .

Another GFS run with low pressure filling over the UK . Cold air to the north trapped there .

i think that depends if your thinking short or long term - i would rather a Jan 87 than a Dec 17.

[Scandinavian High.]

Is high pressure trying to get up to Scandinavia . 

[Catacol]

8 minutes ago, BartyHater said:

On the face of it the 180hrs chart from the GFS06 appears primed to deliver the Artic goodies, as soon as what looks like the last Low on the train exits stage east… but unfortunately the much vaunted Russian/Kazak High is likely to go from being our potential cold weather friend into enemy No1, by effectively trapping the trough smack bang over the UK going into week 3 of December…IF of course GFS turns out to be right with this trend it toying with.

 

Enemy? No. It is aiding a significant attack on the strat vortex. And then - as it fades - the pattern shifts east to west. Clear on both ensemble means today. So far the trend for this month, after a cold spell that I think has generally over delivered, is sticking to the script.

[Vikos]

22 minutes ago, Lukesluckybunch said:

Problem is no cold air too tap into now from the east..due to that Siberian high as Nick was saying.the trend is good though,with heights building toward greenland..so a few tweaks come the 12z..and it could be a better outcome

Well, we all aren’t living in a favourable spot for prolonged cold and snowy weather, and climate change is doing the rest. 
my hopes remain that the El Niño effect will affect us in the later season. Again, as long as US/Canada remain “warm”, and the PV and the jet aren’t doing as they should do, everything is on the menu. 
 

sometimes the chase is more thrilling than the actual outcome (at least for me)

Edited December 3, 2023 by Vikos