[Model thread discussion - cold spell looming]

Who said it’s all over.  This would be so cold and snowy

[Model thread discussion - cold spell looming]

Reasons to be cheerful.

If it’s obvious to a total amateur like me...... no Atlantic to back up lows.

The reliable is 4 days at best (RT in my crayon below).  The ‘warm up’ is already being moderated, get back under the 30 yr mean !!!

Look at that spread beyond and into fantasy island some 15 degrees celcius so i would worry at all.  All of the trends have been for cold.   When the ECM latched onto it, the GFS gave up the ghost, (probably not able to handle the series of SSW’s and using default bias) but it soon came back on board.  
 

We are in a prolonged cold spell which even here in the far south of Wales, frosty mornings have been nice to have, and frequent too. (Certainly more than in recent years). 
 

I cannot see it ending in February....

[Model thread discussion - cold spell looming]

Has nobody noticed that the Atlantic is broken?  Up on blocks so to speak.  Factor in good coupling post multiple SSW’s and any “breakdown” just means snow.  We are not having anything mild or zonal for quite some time to come.

the ‘mild period’ is only going to be mild relative to now, which isn’t very mild at all and increasing all members will dip back under the 30yr mean imo.

shortwaves? Bring em on!!!

 

[Model output discussion - deep cold inbound?]

6 minutes ago, chris pawsey said:

Can I ask, when do people consider FI to be now? 

5 days

[Model output discussion - deep cold inbound?]

1 hour ago, Ice Day said:

Look how the 6z is losing the dartboard low in the Atlantic seen on the 0z at 150, and disrupting and stretching it more. This will help it slide more and keep the bitter air in.

  

I really think this is going to be the direction of travel and the breakdown maybe a fair way off.  We're on the cusp folks! 

All Atlantic lows become sliders as they get crushed by sheer strength of cold and nothing behind them as back up to drive em through 

[Model output discussion - deep cold inbound?]

6 minutes ago, Snowman31 said:

 

Para at 150. Looking good 

Seriously, how can the Atlantic ever recover from that?  Look at the drain potential of that black stuff Siberia and beyond.  Gallons of the stuff filters our way.  Heavy cold  

[Model output discussion - deep cold inbound?]

3 hours ago, Mike Poole said:

ECM T96 v UKMO:

Notice the two lows to the southwest, one thing I’m increasingly starting to notice is that UKMO is reluctant to develop deep lows here, ECM a bit more, and GFS over the top.  I’m convinced that in this region, massively affecting the UK, the UKMO has it right.

There’s a mass production facility for them just off Canada.  With a bit of luck we get persistent sliders and entrenched cold 

[Model output discussion - deep cold inbound?]

1 hour ago, Ice Day said:

Actually, this Icon run is turning into a stunner out to day 7

  

The plucky little ICON

[Model output discussion - deep cold inbound?]

This is why you dont have to panic.  Once we reach the bottom it’s a long way to go to get back above that 30yr average.... 4 or 5 days out at best is all you can really read into for specifics the rest as you can see really is fantasy island and the vortex undergoes a 4th warming event..... long cold spring on the horizon.  The tomatoes will be slow this year

[Model output discussion - deep cold inbound?]

Just now, Tim Bland said:

Would like to see signs of a bit more Longevity in the cold spell starting to appear soon. Otherwise it looks like a 4 / 5 day spell breaking down on Thursday. Let’s hope we see a repeat of the 00z GFS soon... if not it’s still a good spell (especially compared to recent years)  which will deliver a covering for many and i’m sure there are plenty of people in the far north east and Scotland who are sick of snow...just keeping everything crossed for the southern members

Don’t worry, the drum has been beating for cold all winter.  And now we have arrived almost at T0.....4/5 days max look ahead from here on in, enjoy as it unfolds 

[Model output discussion - deep cold inbound?]

18 minutes ago, Snowman31 said:

Icon better and further south.. 

some ridiculous slider potential out to our west on that chart

[Model output discussion - deep cold inbound?]

4 minutes ago, Uncertainy said:

This is low number 5. The previous 4 have all gone under the block. Even mambo number 5 is having a go! Go on my son!

Wat

Bonkers really, particularly if minus double digits 850’s are in place....

[Model output discussion - deep cold inbound?]

4 minutes ago, northwestsnow said:

Are we on the cusp of a Feb 1991 here?

Its certainly a similar time of year, I'm sure of it....

It is possible.  The op at 144 ish has a conveyor belt of lows queuing up to roll along the southern coasts.  Surely some  massive snowmaking potential in there with the cold from the east setting in....

[Model output discussion - deep cold inbound?]

There’s barely a member above the 30 yr average.  Everything is down down deeper and down right until the end of the semi reliable timeframe.  Is that called agreement?

Beyond 120  and often 96+ is guesswork.

this is how a prolonged spell digs in....

agreement on cold.  Next question is can it get a foothold?

 

[Model output discussion - is the beast awakening?]

1 minute ago, danm said:

How many times during a run up to a cold spell have we seen variations on a theme, wobbles in an operational and ensemble run, before things correct back? Probably every cold spell I can remember. That’s not to say that a downgrade for some on the GFS and GEFS this evening should be ignored, but unless that trend continues over the next two to three GFS runs, and until it is joined by the UKMO and ECM (which both had stellar runs just a few hours ago) I really wouldn’t be getting overly downbeat. These things are par for the course. 
 

 

I think everyone is still suffering PTSD from THAT ecm......

[Model output discussion - is the beast awakening?]

The overwhelming message is this:

All the trends have consistently been for a drop in temps.  Across all models, by far and away the trend is towards cold.  Flitting between just cold (like now and most of this winter) to VERY cold as is now coming into view.

We are approaching our third assault on the polar vortex in a little over a month

So, also no Atlantic and it would appear that the biggest spoiler could be weak defences from Mediterranean air.

 

my money is on the plucky little icon.  It seems to be good at picking out the final solution in a shorter term this year.  Or maybe that’s just me.  Either way terrific charts this last few weeks and we are approaching T0

[Model output discussion - is the beast awakening?]

DONT PANIC CAPTAIN MANNERING SIR.

the trend is a nosedive and a decent one at that.  That is all so, feet up and occupy thine selves in readiness for a sustained bout of monkeys.

[Model output discussion 24/01/21]

7 hours ago, tight isobar said:

The one to watch today..certainly imo..@ecm 

You’re back!!

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

https://www.netweather.tv/forum/topic/33865-the-severe-winter-of-1928-29/

this sounds awfully like this year and the set up post SSW is almost identical..........

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

Where is @tight isobar when you need him?

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

Classic flip coming up with some insane runs next week. And also some very mild wet solutions or just cold and wet.  The additional vortex split will not be helpful to much clarity on a run by run basis.  Time to reduce frequency of checking, its wasted time for a few days yet

[Model output discussion - cold spell approaching?]

Reasons to be cheerful.  Tomorrow’s forecast will be white for many, enjoy it whilst its there!

the trend still says Down!  This ‘blip’ on Sunday / Monday is slowly being eroded and from the 20th they are clueless.  Don’t forget all those inputs being collected from weather balloons etc in an already shot NH....... there is no Atlantic force, and we have a good 6-10 weeks left yet, bearing in mind that March can be quite a snowy month.......

[Model output discussion - cold spell approaching?]

Temperature drop imminent.  A much more organised set here.  Lets get that little hump under the line and outlook is back as it overwhelmingly has been all winter- cold.  And it has been cold.

[Model output discussion - cold spell approaching?]

Vile chart for a coldie but the models are not forecasts, they just generate multiple scenarios that people use to make a forecast.

 

As a total newb to this im just sticking to one chart - the 850s gfs ens.   And what that chart shows us in black and white is that beyond day 4/5 most models are useless.  (Circled red)
 

what I do know though is that whilst they might be not very specific and very sensitive to variables in their inputs, trend is how you make sense and the trend has been and remains cold...... on we go!

[Model output discussion - cold spell approaching?]

Wavy but universal agreement. 
 

i do not like it at all but thats what we are getting in the very short term.... however.... they ALL go colder in the relatively near term, even on the ‘disastrous’ latest run.  I don’t see any cause for concern the trend has been cool and cold all winter and we are only 5 weeks in really.