Model Output Discussion - Spring Has Sprung

[Lukesluckybunch]

2 minutes ago, northwestsnow said:

take 6z right now!!

I think start looking northeast after this timeframe..fun and games could begin!

[northwestsnow]

6z is cold,  cold ,cold.

Can only hope EC follows along those lines..

[Lukesluckybunch]

Backdoor easterly set up..as the hp is beggining to sink over the uk

[IDO]

There were signs on yesterday's 12z that background signals may be showing as we saw the flow slow down. Mainly on the GFS and today's 0z and 06z run with that theme. A watching brief to see if this is what is likely, and if it is, how will it develop?

Nice to see though, D8-14:

[AO-]

Good Morning 

It seems like I'm joining at the right time. The GFS operational is great up to day 13. The EPSs this morning have improved a bit, but it is still just the operational. I would like to see the ensemble in line with what the operational is showing. Across model agreement untill day 10, which is nice. Maybe the background drivers are (finally) delivering in the charts.

[Met4Cast]

My thinking is starting to shift from "not much chance of notable cold" to "a possibility of notable cold". I'm still not convinced that we're going to see sustained high latitude blocking despite the current momentum surge from the tropics in the form of a very strong +MT event. 

Whilst the MJO is not to be taken into isolation, phase 7 is more supportive of Atlantic ridging (indeed, NWP modelling has started to signal this more strongly in recent runs) rather than Greenland or Scandinavian blocking. 

A colder spell of weather, at least relative to what we have at the moment seems likely post 7/8th February but prolonged deep cold with widespread snowfall risks continues to be a lower likelihood to me. Another dry northerly before the high topples? Potentially. 

Saying that - We don't necessarily need mega blocking to produce snowfall at this time of year so even a relatively mediocre could bring about snowfall.

Edited January 27 by Met4Cast

[Lukesluckybunch]

Better mean at day 10..ridging South of greenland..but them Euro heights still hanging around!

[Cambrian]

0z ECM nails it from my perspective, day 1-15 animations for the control (in effect the op past day 10) and mean.

The main PV moving east out of Canada / Greenland to Scandinavia during the next week, before regathering and drawing a proportion of the Scandinavian lobe back west, on the op and reinforced by the mean.

 

Chances for a northerly blast for a few days around day 10 before the pattern flattens again, except with the jet stream markedly further south, the flow is by then zonal but cold. The jet stream on the op and the mean T850s.

It’s not deep cold but far from wall to wall mild either, the clear trend for colder air further and further south into week 2. 

 

It’s what the op is showing signs of doing at the end of the run is what is most eye-catching though. The regathering of the PV over Greenland is brief, the (by then) Siberian lobe is dominant, and successive systems are being passed from Greenland southeast to the base of the Siberian lobe. 

By the end of the run, the remnant limb of the PV over Greenland looks like it’s going to catch the same train, swing south east and reconsolidate the PV from Siberia through to Scandinavia, with very little PV left back out west. A system is working its way through Canada and the US and is looking to pump heights up into Greenland. Very interesting.

A very long way off for now, but we’re getting close to the beginning of the initial very well telegraphed evolution with regard to the PV now, so for me, this is getting exciting - from a mild start, the models showing signs of being on the all go from here into a progressively colder February.

Have a great day.

[Anthony Burden]

Morning all,GFS 6z bringing the colder period into the 9/10 day  still lots to get resolved but promising is the word High pressure to the northwest looks the form horse at present along with a very cold northerly as the the met office extended hinted who has gone  from easterly/northeasterly to northerly all a good direction in my eyes for cold lovers with a chance of the white stuff.

[AO-]

The Control joining the operational to some extent. All depends on the developments of the shortwave near the eastcoast of the US/Canada. In the operational the WAA was much better, but still there is perspective in the Control at day 10. 

[WinterOf47]

I am wondering how much of this trend we are seeing for a mid Atlantic High, possibly switching to a brief GH is due to the brief SSW we had recently. Has that done just enough to mess up what looked like an endless Iberian high? The GEFS and OP runs are both holding lots of hope for some activity from 10 days time as others have said, and that really is the last window for some proper lasting winter weather, short of a BFTE. For the movement I am going to enjoy the sun and warmth though. 

[Kentspur]

  @Anthony Burden   Thats a real shame they've dropped the Easterly wording for most of the country much less chance of snow for places that haven't seen any. I've a friend in Aberdeen who was fed up of the snow I was wishing it down here but it didn't work lol sods law it goes to where its not wanted. If that's the case that the Met are only seeing dry Northerlies for most of us, so be it I'm still hopeful as late winter early Spring we do always seem to have them much more commonly and what with all the background signals AO and NAO going negative. Fading + IOD El Nino winter im sure we will see something crop up. I can't remember the last time we had snow in January possibly 2013, February was much more recent

Edited January 27 by Kentspur

[Dennis]

MJO event with GH

 

[Froze were the Days]

  @northwestsnow Problem is mate it's the 6z!...doesn't verify well and to be fair I don't take much notice full stop of the GFS in FI, maybe some trends.

[feb1991blizzard]

  @Dennis

MJO dying a death in 7.

[blizzard81]

  @feb1991blizzard Doesn't it go back into 6 on that chart?

[Mike Poole]

  @feb1991blizzard The MJO has been modelled to cave into the COD for what seems like ages.  But each day’s actual data verifies at higher amplitude than modelled just the day before, it seems.  I think there does have to be a chance that it will sail through 7 at similar amplitude to currently.  But you wouldn’t bet the house on it.

[Dennis]

  @Mike Poole

true status is this 

[AO-]

Didn't Anyone post the fact that the GFS operational is an outlier? At least for here it is. Trendsetter would be nice. Nevertheless it seems like bit by bit the EPS improved for the second week of February. 

[Rain All Night]

On 26/01/2024 at 11:45, RainAllNight said:

0z deterministic runs, Fri 26th to Fri 2nd

GEM continues its streak of maverick runs, this time sending some of the high pressure west into the Atlantic. On all the other models it's looking mostly settled down south, apart from possibly Monday/Tuesday. Would be interested to hear comments from anyone more knowledgeable about sunshine prospects?

0z ensemble means, Fri 26th to Fri 9th

GEM wants to offer us some interest from the northwest around 3rd/4th Feb, but its two bigger brothers are not keen.

0z/6z deterministic runs, Sat 27th to Sat 3rd

This doesn't look like it will manage to be an uninterrupted dry period for all of us, with disturbances running over various parts on Monday and perhaps again on Wednesday (UKMO is most aggressive with that).

0z/6z ensemble means, Sat 27th to Sat 10th

Some obvious interest emerging to the northwest from around 3rd Feb (beginning just after the T+168h frame of the op runs that I've presented above), peaking around 6th/7th. A week later and the signal has faded but it isn't gone completely, which at that range should be enough to sustain our interest.

Edited January 27 by RainAllNight

[Dennis]

50hpa postion and jetstream ,also see the vortex break (2 parts) by the GH

 

Edited January 27 by Dennis

[Cambrian]

6z GEFS shows the Atlantic jet stream splitting around the sinking high pressure at day 10, as it dives southeast through the UK and Ireland into Europe to define the southern flank of the developing Scandinavian trough. 

The setup is an enduring one - the day 14 heights and anomalies shows a maintained northwest-southeast alignment of the heights contours through Western Europe, the area sandwiched between low heights to the northeast, part of a broad trough extending south into Central Europe, and positive heights to the northwest, extending up into southern Greenland. 

It’s looking like a mean northwesterly flow and fairly cold by that stage, with the 552 dam line running through the far southwest. This is a very sound basis from which to move forward to the 12z’s. 

[Kirkcaldy Weather]

Wouldn't be surprised seeing a bit of flooding and potential rainfall warnings particularly for parts of Wales most likely Northwest and into Northwest England into Tuesday with increasingly heavy precip running along the boundary of colder and milder temperatures.

[Jacob]

12z GFS is looking different, less annoying lows in the Atlantic and more robust Canadian highs, better lows to our south but the PV is further east

Edited January 27 by Jacob

[I remember Atlantic 252]

but not looking forward to this rain event on Monday, expect warnings issued for Midlands area