Model output discussion - into the start of Winter

[SMU]

ECM 12z goes for 70cm snow over ironically 'snowdonia'

[nick sussex]

Northerly topplers often get modeled too far west initially and then as the clock ticks down they get shunted east but this current set up is different so it’s highly unlikely there will be a change in terms of where the coldest air goes .

The blocking to the east allied with the amplified upstream pattern lock in the low unfortunately.

So it looks like a lot of cold rain with some snow to much higher elevations.

A lot of patience is going to be needed providing the upstream pattern remains favourable . 

[sheikhy]

Just now, Steve Murr said:

ECM 12z goes for 70cm snow over ironically 'snowdonia'

If we can just get it to shift another 100 miles east then we got more areas have a chance!!but i doubt thats gona happen now!

[Weathizard]

Frustrating.

[Tim Bland]

I know I’m like a stick record but so frustrating to see these Synoptics but no cold uppers anywhere near to tap into. All the cold air is in the other side of the northern hemisphere

[Matt H]

It would be such a shame if our first properly blocked pattern in December in years was let down by the lack of cold 850s around. Hoping if we maintain the pattern for long enough during December then eventually we’ll get lucky. Big if though.

[I remember Atlantic 252]

2 minutes ago, Tim Bland said:

I know I’m like a stick record but so frustrating to see these Synoptics but no cold uppers anywhere near to tap into. All the cold air is in the other side of the northern hemisphere

Surely that's the time of year? way too early yet, Feb is coldest if you get the right setup

[desverger2]

Although uppers don't appear anything special the UK is under a cold pool for a long time. Id expect dew points to keep dropping along with the 0 degree isotherm. Might be a slow builder but I can't rule out snow atm and if we get that second bout of amp we can probably add a few more days with an opportunity for deeper cold to come. Its a slow builder but the best spells are like this 

[mulzy]

Sadly it looks like cold rain for many after this evening’s NWP episodes - only the GEM looks good for more widespread snow.

ECM goes shortwave crazy in FI - probably a bit unbelievable but time will tell as ever.

[Scott Ingham]

This is a slow building cold spell. I'd expect uppers and dew points to slowly drop day on day. I couldn't rule out snow surprises. Wait till the low drops south and use the higher resolution models because looking at 850s this far out is pointless 

[SMU]

Just now, Scott Ingham said:

This is a slow building cold spell. I'd expect uppers and dew points to slowly drop day on day. I couldn't rule out snow surprises. Wait till the low drops south and use the higher resolution models because looking at 850s this far out is pointless 

 

ECM by day 7/8/9 has surface temps of about 4-6 for the SE / 2-4 for the midlands & close to Freezing for the far North!

[Tim Bland]

7 minutes ago, I remember Atlantic 252 said:

Surely that's the time of year? way too early yet, Feb is coldest if you get the right setup

I wouldn’t say approaching mid December is too early for cold weather from that kind of blocking, we are just unlucky on this occasion 

Edited November 29, 2020 by Tim Bland

[northwestsnow]

Just now, Steve Murr said:

 

ECM by day 7/8/9 has surface temps of about 4-6 for the SE / 2-4 for the midlands & close to Freezing for the far North!

Precisely why the really cold uppers are not so vital when the westerly feed is interrupted.

Looks quite stagnant, coupled with low solar input , cold temps at surface.

[nick sussex]

The ECM isn’t helped by a very unfavorable phasing of shortwave energy over the UK and that to the nw.

The day ten then anchors the low west of Iberia and drags out the boredom! 

I totally get the frustration ! 

[Scott Ingham]

1 minute ago, Steve Murr said:

 

ECM by day 7/8/9 has surface temps of about 4-6 for the SE / 2-4 for the midlands & close to Freezing for the far North!

Exactly mate. No point in getting hung up on 850s is there. Let's get the pattern nailed first. Im sure there will be a surprise or two closer to time 

[DavidS]

18 minutes ago, Steve Murr said:

ECM 12z goes for 70cm snow over ironically 'snowdonia'

Bank! Won’t happen, but bank. I’ll take the 1 to 2 inches for my location in South Wales.

[Tim Bland]

4 minutes ago, northwestsnow said:

Precisely why the really cold uppers are not so vital when the westerly feed is interrupted.

Looks quite stagnant, coupled with low solar input , cold temps at surface.

Depends what your after I suppose If it’s cold then it’s game on...if it’s snow then your probably out of luck away from highest ground. It can be 0c at ground level but without colder uppers (at least -3c at 1500m) you will get freezing rain at best

[northwestsnow]

While a true Cold spell is not indicated on EC a more seasonal outlook is...

There is low temps, well below in some places, and probably some frost etc...

Beats wind and rain off the Atlantic in my world.. 

[Nick F]

4 minutes ago, northwestsnow said:

While a true Cold spell is not indicated on EC a more seasonal outlook is...

There is low temps, well below in some places, and probably some frost etc...

Beats wind and rain off the Atlantic in my world.. 

But, it will be wind and rain off the Atlantic from Thursday! Albeit on the chilly side.

Wave over Ireland Thursday deepens rapidly into a 964mb low over Wales on EC by Friday morning.

Edited November 29, 2020 by Nick F

[Daniel*]

I did say Snowdon the other day 71.1cm on ECM that’s 28” you can’t expect all of that to be end depth but a huge potentially historic snow maker firming up for high ground of N Wales.

[northwestsnow]

Just now, Nick F said:

But, it will be wind and rain off the Atlantic from Thursday! Albeit on the chilly side.

I know, I'm focusing on thereafter Nick !!

[nick sussex]

Looking at the day 7 into 8 on the ECM given it’s that far out could still change.

The upstream shortwave is moving se but then phases with some shortwave energy over the UK .

If you can get a clean se track then this would lead to a more favourable day 9 and 10.

 

[bluearmy]

14 minutes ago, nick sussex said:

The ECM isn’t helped by a very unfavorable phasing of shortwave energy over the UK and that to the nw.

The day ten then anchors the low west of Iberia and drags out the boredom! 

I totally get the frustration ! 

I wouldn’t get too bothered by frustrating ops post day 7/8 just as we shouldn’t get over excited by those showing wintry nirvana at that timescale .....this isn’t a standard type evolution upcoming

and you just mentioned the phasing of the disrupting trough with the low heights just to our ne ..... how likely is that to verify ? 

incidentally, the gefs look a bit more mobile off the Atlantic late on compared to previous runs ...

 

Edited November 29, 2020 by bluearmy

[Sweatyman]

3 minutes ago, Daniel* said:

I did say Snowdon the other day 71.1cm on ECM that’s 28” you can’t expect all of that to be end depth but a huge potentially historic snow maker firming up for high ground of N Wales.

There will be surprises. There always is! You see...

[booferking]

4 minutes ago, Nick F said:

But, it will be wind and rain off the Atlantic from Thursday! Albeit on the chilly side.

Wave over Ireland Thursday deepens rapidly into a 964mb low over Wales on EC by Friday morning.

Rain totals for the entire EC run for those interested.