Model output discussion - here comes the beast!

[kold weather]

GOOD 144hrs from ECM and an upgrade towards the 12z GFS.

My word though there is so little room for error for those in the north, in the south there is a little more to play with, even with the 12zUKMO.

[Captain Shortwave]

I think this is pretty good, a middle ground between the UKMO and GFS solutions so a direct hit for the UK and much better than the morning run.

   

Snow moving from east to west along that kink.

[Man With Beard]

ECM T144 - yes the cold coming at us more directly - look at the cold in Scandi - this run could be incredible

[WalsallWeather123]

Great chart at T144. Brings widespread cold and incoming snow showers. Would prefer HP a tad more north but lots of small changes will happen closer to the time. Proves GFS OP was an outlier

[tight isobar]

Run of the day coming up here ecm 12z.

 

And everyone involved!!

12z ecm

 

Edited February 21, 2018 by tight isobar

[chris55]

1 minute ago, Quicksilver1989 said:

F5 F5 F5 F5, yessssss...  lol

Much better 

Note that little trough/kink moving through Wales, some snowfall on that you would think  

[SMU]

heavy snow tracking across the midlands to wales !

[Johnp]

Just now, Captain Shortwave said:

I think this is pretty good, a middle ground between the UKMO and GFS solutions so a direct hit for the UK and much better than the morning run.

   

Snow moving from east to west along that kink.

'Pretty good'.

Imagine saying that a few weeks ago.  We would have been excited if one ensemble member was showing that at day 15 in the past!

[Banbury]

ECM good so far 

[Snowy L]

ECM perfect

 

 

-10 uppers widely on Monday then we get a shortwave right in the middle of the country on Tuesday.

[winterof79]

2 minutes ago, Captain Shortwave said:

I think this is pretty good, a middle ground between the UKMO and GFS solutions so a direct hit for the UK and much better than the moaning run.

   

Snow moving from east to west along that kink.

Edited sir yes its a fantastic run so far

[nick sussex]

A very good halfway house between the GFS and UKMO. The ECM a bit slower than the latter to start evolving to the Omega Block.

You don’t want the high like the GFS being sucked eastwards .

 

[kold weather]

850hpa temps are not as low at 144hrs purely because of a shortwave coming across the UK. This feature has been slowly coming down the line.

So far we have the GFS and the ECM agreeing, the UKMO deciding to do something else. We are still no closer to having any agreement poast the first 24hrs of the easterly flow onthe 26th.

[Southender]

Lovely ECM. Cold with more organised snow moving East to West Tuesday.

[SMU]

Pressure on the NE part of the block @144 should instigate westward forcing of the upper cold pool-

Is this the jackpot run????

[Mike Poole]

The epiglottis opens at T168 on ECM.
And spewed towards the UK is a torrent of frigid air: -16 uppers incoming perhaps?
This is the middle ground at the moment.

[ICE COLD]

168 get in there my son 

[bobbydog]

ahhh... thats better...

peace and harmony descends on the model thread. ?✌

 

 

yeah right!....

[ZK099]

5 minutes ago, chris78 said:

Please dont take this the wrong way, I am not for one minute saying its all gone tits up,  but the second warming doesnt just affect the models, it affects the weather too, what if they effect is to dilute the strength or reduce the longevity of the cold?    Lots of people have made the point you make, but all seem to assume the SSW will make the models wobble and the settle right back on the ultra cold solution, well maybe they wont?

Yep, I never said whether the warming would or wouldn't enhance/dilute the cold spell. I just said that the models may not have a good handle on the effects of it- they were all over the place after the initial SSW. @Catacol and @chionomaniac (or one of the two ?) mentioned that they thought the secondary warming would in fact increase the chances of a prolonged cold spell. They have been spot on regarding this so far, therefore I'm inclined to accept what they're saying. 

[winterof79]

Oh my days 

[Snowy L]

Just now, Steve Murr said:

Pressure on the NE part of the block @144 should instigate westward forcing of the upper cold pool-

Is this the jackpot run????

Yes looks like most of the country will be hit aside from maybe the far North.

 

[Weather Wonder]

Its about time i did a post on here which takes more than a couple of minutes to type so here we go.

Going to start off by quoting @Paul will save me alot of time posting charts and all from an unbiased source

6 hours ago, Paul said:

Here's a look at the 00z forecasts for 1200 Monday, from the last 11 days on the GFS and Ensembles, plus the last 5 on the ECM. 

Yesterday the GFS and Ensembles did have the cold coming a touch faster, but in the main you'd mostly call it variations on a theme, barring a few big wobbles here and there. The ECM has had the odd wobble but has actually been more solid on the timing of the deeper cold, if anything bringing it forward a tiny amount today. 

GFS

GEFS (ensembles)

ECMWF

So now we have the previous outputs we can start to come to a conclusion here, i will start with the most obvious.

There is NO strong easterly flow as was previously modelled.. this is key as it will push showers well inland and allow the colder sub -10 uppers to arrive quicker and remain over the british isles. For the majority of the southeast in particular for heavy settling snow the charts at the moment are just not enough.

As above the slack flow off the continent also increases the risk of shortwaves developing hence the varied outputs we are seeing now, the fact the models cant decide on the stregnth of the block is even more concerning.

This should go without saying but with March around the corner and the increasing stregnth of the sun we all need low temps to sustain snow cover for more than a day or too,m -5/-10 850s just wont cut it this time of year without a cold high pressure being in situ more so in the south and would be difficult in the north withouth altitude in this setup as currently modeled.

With the output downgrading the potential consistantly i think we should all be a bit more realistic, im not saying its not going to snow but based of the input, the best most places can hope for is a four day cold snap with a chance of snow a high posibilty but severe snow away from favoured spots is unlikely IMHO

 

 

[BLAST FROM THE PAST]

10 minutes ago, Steve Murr said:

ECM 144 Is a boom for pretty much all of the UK except the extreme north & west

icelandic shortwave sliding east rather than digging which is what we want...

Hopefully some folk will relax.... ECM is an absolute beauty and I don’t see why that isn’t the way forward.  Much cleaner, bitter and very snowy.  This run HAS NAILED IT.....I am very confident on that

 

BFTP

Edited February 21, 2018 by BLAST FROM THE PAST

[Banbury]

Just shows the uncertainty in the outlook 

[Purga]

The cracker continues to 168hrs