Model Output Discussion - A cold start to Spring?

[Unpredictable Seasons]

3 minutes ago, Kentspur said:

Nope the chart posted shows light blue shadings over my area

As for geography it was my strongest subject and i taught the class during a Geography tutorial at uni the tutors had that much faith in me...

Totally replied to the wrong post apologies Kentspur no doubt mate great reply...

 

[nick sussex]

Mogreps has been quite jumpy , similar to the op runs.

For example the 00hrs run removed the cold solutions for London for the 11th into 12th.

 

And then some made a return on the 12hrs run . There’s also a large degree of scatter for just 4 days out . You would only really see this type of scatter at short range in a pattern with a small margin between colder and milder 850 values related to  shifts in track of lows running into the UK.

Edited March 6, 2023 by nick sussex

[tight isobar]

The eps 12z therms/ @ 2m temp outs highlights the divergence on transient precipitation types. For this period Tuesday/ Wednesday, marginality is poker play!.. the moisture incursions are on point- and it’s  all eyes on bulbs/ dews south of mid England/ wales!!.. then it’s how much advance fronts make... there is likely a classic rain to snow- then revert for lower levels. Although this is as fickle as it gets for predictable outcomes!! Somewhere “likely mid- upper England/ wales .. are going to get a more than noteworthy snow twist... we watch and wait!!!

[tight isobar]

Longer term- it’s increasingly likely of a short milder interlude, as fronts absorb and make inroads- b4 the cold starts plunging bk once more... “ highlighted perfectly on the 18 supporting ens.. @ London ones!!

[Frigid]

Good agreement on the cold coming back with the mild spell not lasting too long.. GEFS 18z and ECM 12z ens shows this quite well

  

  

As for surface temps, well if the 18z is correct it could be quite severe.. lows of -9C in Manchester and continuous ice days in March is unheard of.

 

 

Edited March 6, 2023 by Frigid

[Cheshire Freeze]

There's a signal for an E'ly in a couple of weeks time- it's not just on the GFS ops, the CFS has been picking it up too

[PiscesStar]

The 18z overnight gfs run is a thing of Beauty if it's cold and snow you're after!! Low after low is shown undercut and pulling in those cold air uppers!! Brrr!! Winters sting is sharp!! 

[Mucka]

Horrible UKMO this morning with bowling ball lows. 

GFS much better than that with at least still cold across half the UK and snow for N England

GEM is much improved over the last run but still gets milder air into N England on the 10th before retreating back S so not the masses of snow for N England that GFS promises

GFS 00z ensembles

Plenty of GFS ensembles have snow for the S on 9th and staying drier in the N while the other favoured option is snow for the N and rain for the S.

So central England seems best placed at the moment but some runs have the mild air into Scotland while others have it so far South that even the S stays dry.

Unless we get a UKMO type solution it could come down to a nowcast for many as to whether they get rain/sleet/snow or nothing.

 

 

Edited March 6, 2023 by Mucka

[John88B]

48 minutes ago, Mucka said:

Horrible UKMO this morning with bowling ball lows. 

GFS much better than that with at least still cold across half the UK and snow for N England

GEM is much improved over the last run but still gets milder air into N England on the 10th before retreating back S so not the masses of snow for N England that GFS promises

GFS 00z ensembles

Plenty of GFS ensembles have snow for the S on 9th and staying drier in the N while the other favoured option is snow for the N and rain for the S.

So central England seems best placed at the moment but some runs have the mild air into Scotland while others have it so far South that even the S stays dry.

Unless we get a UKMO type solution it could come down to a nowcast for many as to whether they get rain/sleet/snow or nothing.

 

 

It sounds like the models are all over the place for this week then, even at this late stage. It certainly makes for interesting model watching and as you say a lot of it will come down to nowcasting and of course lamp post watching

All areas still in the game so will be interesting to see how all this pans out and who gets lucky.

[geordiekev]

1 hour ago, Mucka said:

Horrible UKMO this morning with bowling ball lows. 

GFS much better than that with at least still cold across half the UK and snow for N England

GEM is much improved over the last run but still gets milder air into N England on the 10th before retreating back S so not the masses of snow for N England that GFS promises

GFS 00z ensembles

Plenty of GFS ensembles have snow for the S on 9th and staying drier in the N while the other favoured option is snow for the N and rain for the S.

So central England seems best placed at the moment but some runs have the mild air into Scotland while others have it so far South that even the S stays dry.

Unless we get a UKMO type solution it could come down to a nowcast for many as to whether they get rain/sleet/snow or nothing.

 

 

Aware those are slghtly varied times but v noticeable how different the US pattern is, which in turn effect the Greeny block. Defo too much spread for confidence beyond 48h

[KTtom]

Be interesting to see what EC comes up with but UKMO comes up with a 'football' low which blows the cold away, even from the north temporarily, can it be wrong at just t96?. If nothing else at least the weather is livelying up a bit.

 

Edited March 6, 2023 by KTtom

[Mike Poole]

The models are really struggling with this.  It depends on what you think the ‘right’ solution is with this train of lows.  I think the right solution is a train of lows starting very elongated and squashed tracking more southerly, but becoming more rounded if and to the extent that the mild air encroaches north, and the heights over Greenland decrease.  UKMO looks too fast with the bowling balls:  

GFS looks to me to have had a better handle on this in recent runs, it just looks more plausible:

GEM also looks to squeeze the lows more:

Having said that, I think the whole track is subject to change, particularly for later in the week.  We need to get an early view of whether the cold is hanging on more or less than the models are predicting once the Atlantic low train starts.

Edited March 6, 2023 by Mike Poole

[That ECM]

Not what we wanted to see. 

Edited March 6, 2023 by That ECM

[Mike Poole]

ECM has swallowed the first low without substantially dislodging the cold at T72:

Really think anything after this point is FI, totally up in the air.

Edited March 6, 2023 by Mike Poole

[Weather-history]

ECM 0z has huge snowfall totals for Northern Ireland/ northern Eire and southern Scotland.

Maybe somewhere will get a historic snowstorm this coming week? The potential is there

[Ali1977]

UKV brings the Wed LP quite far north, with the Friday one heading to Scotland

The arpege isn’t so far north with Wednesdays and hits midlands north with snow on Thurs!! 
 

still non the wiser 

[EML Network]

If I was living in the Lake Districts Id be getting very very excited right about now.

but if you need proof that PPN can crop up at any time during this week.

 

look no further than right now

GFS PN for 0600

Actual

 

 

[Jacob Gamer]

May someone tell me how to see the line graph ecm ensembles on the website called Meterologix?

[IDO]

Looking like the Iberian high is a recurring theme on the GFS from T90-T252, so cold zonal, and the snow boundary looks somewhere north of the Midlands. GFS then brings back the Azores high after D10, so there is potential for Atlantic ridges or waves. ECM similar:

So maybe firming up on the long wave pattern going to D10. As for the finer detail, that looks close to call,  the channel low for the south with the GFS now missing the snow:

Those lows and trailing fronts only need a 100-mile shift north for a dumping for the south and still time for corrections.

Edited March 6, 2023 by IDO

[Ali1977]

Also noticeable is the ENS with even Fridays low staying south, the control and ENS show this - and fir the ENS to show snow further south that far out that’s quite a shift 

 

The cold hangs on with the GEFS too 

Edited March 6, 2023 by Ali1977

[sheikhy]

Well that was something from the 00zs!!!!cant say i didnt expect that!!!hopefully a push south on the 06z and 12zs!!!ukmo went mental with the low at just 96 hours!!

[That ECM]

Which to my mind goes against ukmo output.

Edited March 6, 2023 by That ECM

[Ali1977]

5 minutes ago, That ECM said:

Which to my mind goes against ukmo output.

With the latest UKV bringing Wed low pressure further north the fax charts could change I guess!! But the ENS are all over, 500 miles difference between day 3s outputs 

[sheikhy]

Just now, Ali1977 said:

With the latest UKV bringing Wed low pressure further north the fax charts could change I guess!! But the ENS are all over, 500 miles difference between day 3s outputs 

Why do i get this feeling if wednesdays is further north fridays shall be further south!!its like a ribbon of lows going up and down!!

[Ali1977]

1 minute ago, sheikhy said:

Why do i get this feeling if wednesdays is further north fridays shall be further south!!its like a ribbon of lows going up and down!!

Seems to be the case on the GFS Control , so could well be!!