Model output discussion - mid-winter

[January Snowstorm]

13 minutes ago, Broadmayne blizzard said:

That'll be the cold spell that hasn't arrived and the one we don't yet know the length of then.

To be fair it's all in the reliable time frame now. Starting tomorrow and Wednesday system is only 3 days away

[shaky]

18 minutes ago, Draig Goch said:

I'm hoping the ECM 12z takes this storm system much further north or south just to keep the worst of the winds away from the populated areas, fingers crossed 

Even deeper by 5mb on the ecm!!

[karyo]

3 minutes ago, shaky said:

Even deeper by 5mb on the ecm!!

Horrible ECM so far! The low goes through Scotland.

[nick sussex]

The ECM has the best upstream pattern at T96hrs slower. Its essential you get phasing at T120hrs between the two shortwaves, over the ne USA and Canada.

If they phase you get a better ridge to the nw, if not then not good.

[I remember Atlantic 252]

3 minutes ago, karyo said:

Horrible ECM so far! The low goes through Scotland.

Your location could still have a 2 day snow window, Thur/Fri, before the Atlantic arrives properly on Sat 20th, could certainly last rest of Jan (11 days zonality)

 

cannot get rid of the 'red' chart???????

Edited January 14, 2018 by I remember Atlantic 252

[ACCOUNT DELETED]

ECM 12z takes a more northerly track 

[That ECM]

Not pleasant. Will be news worthy.

[karyo]

1 minute ago, I remember Atlantic 252 said:

Your location could still have a 2 day snow window, Thur/Fri, before the Atlantic arrives properly on Sat 20th, could certainly last rest of Jan (11 days zonality)

 

I doubt it with those uppers.

[andymusic]

4 minutes ago, Draig Goch said:

ECM 12z takes a more northerly track 

at this rate it won't even hit the uk at all the way it's going lol

[karyo]

6 minutes ago, nick sussex said:

The ECM has the best upstream pattern at T96hrs slower. Its essential you get phasing at T120hrs between the two shortwaves, over the ne USA and Canada.

If they phase you get a better ridge to the nw, if not then not good.

At 120 hours it is still flatter than the 0z so not a good trend.

[feb1991blizzard]

2 minutes ago, karyo said:

At 120 hours it is still flatter than the 0z so not a good trend.

Yes - Flat.

[SLEETY]

Ecm  lot better at t144 Still showing Northerly  maybe it’s not over yet,huge difference between ecm and gfs UKMO 

 

 

 

[Johnp]

1 minute ago, feb1991blizzard said:

Yes - Flat.

It's not flat at all at t144. 

Hopefully we can get some trough disruption at t168.

[Weathizard]

Difference between the GFS and ECM at 144.. madness

[Mucka]

"Hello everybody! I'm the Azores high!"

What a turnaround it has been.

Just 24 hours or so ago NW England looked like getting 5 days of cold and snow shower followed by a NE and the chance of more cold and blocking.

Today the same locations are looking at a 24hr event on Tuesday followed by  a possibly damaging storm, followed by 24hrs of wintry showers then mild wet and windy.

The only glimmer of hope is that lesser models GEM and JMA don't develop the runner and so keep to it further South.

But given the big 3 all blow it up then that is just straw clutching.

Possibly for those away from the NW and central areas the biggest downer is the loss of the Atlantic ridge from the output.

I feared this would happen (low deepen and tack north) as soon as I saw the very first GFS run that had it stay to the South as a shortwave trough as it is often the case with these Atlantic features at the base of a trough. Atlantic Lows that get programmed further South over time are those that undercut blocking, runners nearly always get corrected North and deepen as we get closer in as the models begin torecognise the potential for rapid cyclogenesis.

I would love there to be another turnaround tomorrow with the runner at least - there will still be subtle corrections North that will push the cold air either further away NE or back South and tiny changes can mean the difference of 100 miles North or South by the time it hits the UK.

If it does deepen as programmed it looks as though it will be damaging, especially the potential sting jet.

Edited January 14, 2018 by Mucka

[blizzard81]

Just now, SLEETY said:

Ecm  lot better at t144 Still showing Northerly  maybe it’s not over yet,huge difference between ecm and gfs UKMO 

 

 

 

Can we trust the ecm though? Nick's lows do phase at 144hrs on ecm. 

[karyo]

1 minute ago, Johnp said:

It's not flat at all at t144. 

Hopefully we can get some trough disruption at t168.

I would be surprised if that flimsy amplification lasts. Either way the ECM is the only major model to show this so it could be overamplifying again.

[Dean E]

Well 24 hours ago, we were starting to get a good idea of next weekend and beyond. Today has put a spanner in the works, with models really disagreeing post Thursday.

The Azores High and this Low moving through on Wednesday/Thursday is really causing some headaches. 

I always bang on about this, but we need to keep the heights low over the Mediterranean. While its not always required, it really does help disrupt the Atlantic and send heights either to our West or North.

ECM 12z is attempting this again, and has been pretty solid on this trend.

Very brief window to be had, it must be said though.

[nick sussex]

6 minutes ago, karyo said:

At 120 hours it is still flatter than the 0z so not a good trend.

It eventually phases and develops more amplitude upstream.

I've decided to cancel the priest! For the timebeing!

[feb1991blizzard]

1 minute ago, Johnp said:

It's not flat at all at t144. 

Hopefully we can get some trough disruption at t168.

Obviously not Bartlett flat but flat enough that the Atlantic is still going to come through again by D8-9 - Matt Taylor agrees with this as well on his long ranger.

[Dancerwithwings]

ECM 144h....Still got the Northerly come Saturday but clear differences a foot.

12Z     YESTERDAY'S 12Z

BUT NOTHING COMPARED TO THE GFS

Edited January 14, 2018 by Dancerwithwings

[doctor32]

The low still tracking across scotland on ECM 12z.

Beeb week ahead forecast has a wintry week with the low tracking as per UKMO and ECM just a bit further south across southern scotland, then they go for a more northerly flow as per ECM +144hr then probably back to low pressure to west/northwest dragging in milder but wet and windy conditions.

Proper mixed bag coming up.

Plenty of snow for higher ground of scotland, N Ireland and N england (some 5 to 7 days of snow for scottish mountains) so really mounting up there!

Storm wednesday night the real story of the week i would have thought with very DAMAGING winds.

Edited January 14, 2018 by doctor32

[SLEETY]

Those long rangers flip as much as the models.im not believing anything past t120 anymore ,too much instability in the runs anymore for that.

Even if the ecm is junk at 168,probably will verify now 

Edited January 14, 2018 by SLEETY

[Dancerwithwings]

ECM.... BIG differences at 168h

    12Z          YESTERDAYS 12Z

[snowray]

3 minutes ago, Dancerwithwings said:

ECM.... BIG differences at 168h

    12Z          YESTERDAYS 12Z

ECM playing catch up and turning into a junk model very rapidly!