Model output discussion - deep cold inbound?

[AWD]

Just now, Tim Bland said:

36hrs into the cold spell. Starts sat eve and this is 36hrs later ...

Yeah, sorry misread your post.  Hidden original post.

[Drifter]

At 192, none of this sliding malarkey - ecm just wants to kick the door down!

Could be epic snow for a few hours before the inevitable thaw. That is certainly in fi though. 

[Cold Winter Night]

1 minute ago, Griff said:

Funny

Edit: I've gone wobble on this run

Cold getting entrenched?

Might not be that easy anymore to remove this cold airmass.

[tight isobar]

The battle is on and snowmagedon for some...  after copious amounts previously-utter madness . The Atlantic making inroads to polar con air.. and screams reload after... !!!!!

Edited February 3, 2021 by tight isobar

[Singularity]

6 minutes ago, kold weather said:

Following on from my previous post, here is 3hrs after that chart, again mild sector pretty obvious when looking at the expected conditions on the model:

Marginal zone runs roughly from the Wash SW towards the IoW.

Once that passes through, it will be more than cold enough again everywhere.

Honestly, considering the surface winds, rain seems unlikely away from right on the coast even with that ‘mild’ sector.

Past two Sundays, I’ve seen snow here when ECM had sleet or rain. I believe it tends to over-modify the mid-levels as air crosses a large body of water.

[Cheshire Freeze]

Looks done by D8 on the ECM, looking to be a snap rather than something more prolonged at this point.

The potential is there to increase longevity though I guess.

[ICE COLD]

T192 

[sheikhy]

I really could not care less what happens at 192 hours!!yeh hopefully it improves in the morning but before that its madness!!

[Gowon]

Just now, tight isobar said:

The battle is in .. and snowmagedon for some... utter madness . The Atlantic making inroads to polar con air.. and screams reload after... !!!!!

If GFS is good at picking up trends then there isn't a reload?

[snowice]

Just now, Cold Winter Night said:

Cold getting entrenched?

Might not be that easy anymore to remove this cold airmass.

I say 144 FI at present enjoy the epic charts.

[chris55]

One thing id say within the context of the thread, is that its important to interpret the runs rather than just take them literally, especially beyond day4-5.

 

 

[Frosty the Snowman]

10 minutes ago, DAVE_ALLEN said:

Just imagine.... If this did that  

Would prefer this...

 

pathway.webp

[Tim Bland]

1 minute ago, Cold Winter Night said:

Cold getting entrenched?

Might not be that easy anymore to remove this cold airmass.

With the 0c uppers reaching the Scottish Borders latitude to our west,  there is only going to be one winner i’m afraid... I hope to do an Ian brown “wtf moment “ shortly though lol

[kold weather]

4 minutes ago, Met4Cast said:

Imagine being in a position where -5c is considered "mild" lol, anything falling out of the sky even in that "mild sector" would be snowfall. 

Except that its definitely not snow on the 12z ECM for the SE at least, we've got the charts which very clearly have an area of rain and sleet moving SW on Monday morning with that small mild sector, see my posts above.

Of course does that mean its going to happen like that? No idea, though the GFS also does have a mild sector briefly as well.

However we shouldn't get hung up really on that, it will turn things perhaps the wrong side of marginal for 6hrs. We have 24hrs at least either side (and probably a fair bit longer) to get plenty of snow down there.

Also, our spot on with the last part of your post, LOTS of snow for most parts of the country, some slight divergence across the SE/EA later on Tuesday/Wednesday puts a bit of a cap on things down there, but snow showers constantly pilling in down the east coast.

[TSNWK]

ECM 192 looks primed to barrell through the atlantic - but will it

this mornings 216 ( so granted 12 difference ) had low pressure over us and out to scandi - where we now have a wedge of high pressure - big changes.

[Daniel*]

21 minutes ago, Snowman31 said:

Surely that mild sector would still be snow as winds from the east?

Dew points what you need to worry about very briefly dodgy in parts of SE. 

[Weathizard]

2 minutes ago, CreweCold said:

Looks done by D8 on the ECM, looking to be a snap rather than something more prolonged at this point.

The potential is there to increase longevity though I guess.

Indeed, that Atlantic low is being modelled strong consistently now. Could be a snowy breakdown though.

To be honest I don’t want a massive long freeze as it will cause vaccine carnage.

[tight isobar]

2 minutes ago, D.V.R said:

If GFS is good at picking up trends then there isn't a reload?

We’ll see what eps says about that in a while!!!!

[kold weather]

4 minutes ago, Singularity said:

Honestly, considering the surface winds, rain seems unlikely away from right on the coast even with that ‘mild’ sector.

Past two Sundays, I’ve seen snow here when ECM had sleet or rain. I believe it tends to over-modify the mid-levels as air crosses a large body of water.

If it was just the ECM I'd agree, but the GFS has a very similar looking profile as well, just a hair cooler

Because of that the GFS literally just stays on the right side, dew points get to 1-2c rather than 2-3c like it does on the ECM 12z.

 

[ICE COLD]

It’s a shame we haven’t got some more blocking left to the north to push the lows further south because there’s still epic cold to the east . Let’s hope it improves on that front in the next few days . 
 

Should add tho UKMO looks better that way at T144 . 

 

Edited February 3, 2021 by ICE COLD

[HellItsHot]

As a long time lurker I can’t ever remember a UK cold spell being initially forecast to last longer than 5-6 days. The models always seem keen to sweep them away, but they don’t always turn out to be right. 
 

Apologies for the OT comment. 

[Northern Sky]

2 minutes ago, CreweCold said:

Looks done by D8 on the ECM, looking to be a snap rather than something more prolonged at this point.

The potential is there to increase longevity though I guess.

It's a 5 day potent cold spell/snap Crewe - if it breaks down as early as shown on the ECM tonight. Often we see entrenched cold air putting up a bit more of a fight, but even if it pans out like shown, I think after next week I'll be happy to start looking for signs of Spring.

[joggs]

That far out I'm sure the models are over egging the lows. Definitely change that far out. A stunning 5 or so days at least to come.

[Eagle Eye]

5 minutes ago, Frosty the Snowman said:

Would prefer this...

 

pathway.webp 295.89 kB · 2 downloads

For everyone confused by this there is a line above the red one. 

[Captain Shortwave]

Given the breakdown is at day 8/9 we could easily see firstly the approaching low modelled to be much less deep and secondly we could still see surface heights to our north/north east exert far more influence on proceedings.

Still five solidly cold days in the south, longer the further north and east you get.