Model thread discussion - cold spell looming

[SqueakheartLW]

2 minutes ago, sheikhy said:

Even better at 96 hours!!cold continental air still well and truly across the uk!

Is GFS up to its usual tricks

1     GFS first spots a cold pattern developing or continuing on

2     GFS drops the idea around 4 - 6 days before it is due and swings back to average or mild

3     GFS returns to the idea of cold from around 3 days from when it is due

You have to hope this is the case as we don't want this cold spell to go out with a whimper or a massive swing to February 2019 weather within days temperature wise anyway. The last thing many would want right now is loads more rain to bring back all that flooding again

[Don]

6 minutes ago, Nick F said:

But there seems some uncertainty to the MJO forecast atm, so not sure we can trust the models extended direction of travel at the moment.

Thanks Nick.  Ref to the MJO, I guess the uncertainty could be an issue for the longer range models too?  Perhaps a bit of a waiting game?!

[sheikhy]

Where my buddy battleground!looks even better at 108 hours!!!!!scandi high stronger as well!!

[Guest]

1 hour ago, Tim Bland said:

Not much uncertainty around the fact it is going to warm up on the ensembles ..

Wow look at that little beauty in there, P16 would be record breaking 21/22C. Yes please lets start spring quickly.

[Battleground Snow]

7 minutes ago, sheikhy said:

Even better at 96 hours!!cold continental air still well and truly across the uk!

Yes, sheikhy,

I don't think we can stop the milder air from encroaching later on Monday, but as Nick has explained well above, is the block to the north east is still very much in play and small adjustments will dramatically affect the UK.

Look for undercutting from both sides around 168. 

 

Edited February 10, 2021 by Battleground Snow

[I remember Atlantic 252]

2 minutes ago, sheikhy said:

Where my buddy battleground!looks even better at 108 hours!!!!!scandi high stronger as well!!

Not sure I like this one, bone dry at 96, in fact all weekend away from extreme W/NW

[sheikhy]

Just now, I remember Atlantic 252 said:

Not sure I like this one, bone dry at 96, in fact all weekend away from extreme W/NW

Yes mate seems to take away the snowy breakdown!!but temps will be frigid across england!!!

[I remember Atlantic 252]

2 minutes ago, sheikhy said:

Yes mate seems to take away the snowy breakdown!!but temps will be frigid across england!!!

Not so sure, this will be a thaw in many places, and no ppn

[Skullzrulerz]

5 minutes ago, I remember Atlantic 252 said:

Not sure I like this one, bone dry at 96, in fact all weekend away from extreme W/NW

I'm happy with it  

Still a bit of a upgrade with the high Is good news

[sheikhy]

1 minute ago, I remember Atlantic 252 said:

Not so sure, this will be a thaw in many places, and no ppn

Still pretty cold mate!!got dew points for same time?!

[sheikhy]

Front at 156 hours was in the north sea on the 00z its now strugglingn to reach wales and is turning to snow with cold dew points undercutting!!

[sheikhy]

This is a massive improvement from gfs if very cold continental temps/dew points and iceicles is your thing!!for snow not much!!going to feel bitter in that south east wind!!

[Battleground Snow]

Much better in the mid term too, if it can just back that cold pool over Eastern Italy towards France, it will prop the high up

[Frigid]

idk about you guys but i'd take cold and dry rather than wet and mild any day. will help river levels in the long run

[MJB]

14 minutes ago, sheikhy said:

Where my buddy battleground!looks even better at 108 hours!!!!!scandi high stronger as well!!

Rubbish run if we want a snow event , the HP is too strong 

[Battleground Snow]

Para has a much stronger scandi high which drags the cold pool much closer to us!

It was thinking about undercutting from the west at 144 too.

I'm going to mashing f5 at 2pm for the met office update

[sheikhy]

The differences at 168 hours are huuge between 00z and 06z!!!!!when i viewed the ukmo this morning i had a feeling something COULD be brewing cos the high at 144 hours was a lot further north compared to the 12z yesterday!!

[MattStoke]

15 minutes ago, sheikhy said:

Yes mate seems to take away the snowy breakdown!!but temps will be frigid across england!!!

Short term ‘pain’ for long term gain. A snowy ‘battleground’ would be nice but not if mild muck quickly takes over for a prolonged period.

Edited February 10, 2021 by MattStoke

[Scandinavian High.]

Nice to see westerly not getting in high to north east fighting back..

[Frigid]

Just now, Battleground Snow said:

Para has a much stronger scandi high which drags the cold pool much closer to us!

It was thinking about undercutting from the west at 144 too.

I'm going to mashing f5 at 2pm for the met office update

That cold pool is so close!! Would take a small adjustment for it to come here.

[adrianh]

The pattern does have the potential to fall favourably if you want another chance of extended cold rather than a battleground event.

Very much in the balance and not 10 days away either. The cold is never too far from our shores and it wouldn't take much of a shift to get it moving towards us rather than staying to the east of us.

[Battleground Snow]

I expect @feb1991blizzard to pop up soon with this chart at 198 on the OP

[SqueakheartLW]

Looking at all of the 00z runs, GFS, GEM and GFS Extended I have picked out the member from each that keeps the cold uppers in for longest, this is uppers at or below -5 at 850hpa on my definition.

GFS 00z

Member 10 keeps the cold in until Wed Feb 17 at 12:00 when the uppers get to -4.9 at 850hpa and it takes until Sat Feb 20th at 18:00 before we are up to the ensemble mean.

GEM 00z

All GEM members are quick to end this cold spell but the one that is slowest to do so is Member 4 which ends it by Sun Feb 14 at 06:00. Far too quick for my liking and it is around ensemble average by Sun Feb 14th at 18:00. Too quick progression to mild on the GEM and it never looks back after this really

GFS Extended

Member 9 on GFS Extended takes longest to end this cold spell by Fri Feb 19th at 06:00 and takes until Mon Feb 22nd at 12:00 to get up to the ensemble average.

Summary

Model          Cold Spell Ends                 Close to ensemble average of run time

GFS 00z       Wed Feb 17th 12:00          Sat Feb 20th 18:00

GEM 00z     Sun Feb 14th 06:00            Sun Feb 14th 18:00

GFS Ex         Fri Feb 19th 06:00              Mon Feb 22nd 12:00

I think we know which one the coldies like me will back here. GFS Extended Member 9. Takes longest of all 3 runs to end the cold spell. Mild lovers will no doubt go for the GEM 00z Member 4 run.

[Frigid]

WAA?

   

[sheikhy]

2 minutes ago, Battleground Snow said:

Para has a much stronger scandi high which drags the cold pool much closer to us!

It was thinking about undercutting from the west at 144 too.

I'm going to mashing f5 at 2pm for the met office update

Would love to see the 2m temps when you post the ensemble graph in a while and dew points!!thing is these changes happenes very early at 60 hours!!!2 things i take from that is firstly maybe gfs is taking into account the cold dense air across the uk is not gona be as easy to shift and secondly underestimating the cold scandi high!!!