Model Output Discussion - Spring Has Sprung

[bluearmy]

30 minutes ago, Metwatch said:

Very good reprensentation of that Greenland high on this plot for the GFS 12z, with the blue colours in the troposphere up to around 250hPa on the 6-8th February, which means slightly reversed zonal winds for a short time, changes each run though as it is in the less certain time frame post day 10.

Interesting to note that it's quite certain now that the westerlies in the stratosphere (above 30 hPa) are going to become even stronger at 60N during the start of next month. So a more pronounced strat - trop disconnection IF Greenland heights does set up, but then maybe the risk of the SPV over-riding any tropospheric led drivers to blocking. The chart below is just another depiction of looking at a model run through different levels of the trop / strat at the same time. NOT a teleconnection / driver like the MJO or velocity potential charts that you may see posted by others.

The Greenland ridge showing in the trop post day 10 is very brief - possibly because it has no support higher up 

The zonal flow for first ten days feb is stronger than average for feb but still below 35 m/s so not at a level that would likely preclude a Greenland block even with a coupled strat -trop if the spv is displaced towards n Russia 

Edited January 27 by bluearmy

[WYorksWeather]

Slightly odd setup on the GFS 18z. Ends up being a cold outlier, but how about this for a bit of ridiculousness.

At T+72, we have a deep low to the south of Greenland, but a block setting up above it.

This low then moves eastwards and deepens absolutely explosively, getting down to 935mb at T+96.

Extreme conditions resulting for northern parts of Scandinavia at T+120, an exceptionally severe storm. Between T+96 and T+120 at one point the central pressure dips below 930mb!

 Here's the mean wind chart at T+96 from the OP run.

130km/h mean winds. That would be equivalent to a mid-range Category 1 hurricane. Absolutely bonkers.

ECM usually has a more realistic outlook on intensification, and though it still becomes a very deep low, the 12z run only deepened the feature to 945mb, and kept it further north.

I think with this we can consider the GFS 18z run a little bit suspect, as the forecasted intensification of the feature looks very unlikely.

 

[Daniel*]

First up ICON keen on something colder a week from now… tpv drained into Scandi…

[That ECM]

Icon gfs ukmo T168.  Quite like ukmo. 
 

To much variation to be confident in anything really, let’s see where ecm goes.

[northwestsnow]

Large differences between UKMO and GEM 168

GEM turns out horrid so hopefully UKMO would be better..

[IDO]

I was hoping, not expecting, that the GFS yesterday was onto something, but the mean remains as per the last week:

The tPV circulates to our north, Greenland to Scandi and back again. The Azores/Atlantic high tries to break north but the jet is not dictated by the tPV, it is running underneath and as it ejects out of the Conus it spawns spoiler lows that cut off any ridge. There are ebbs and flows within the LP systems off the jet and the circulation of the tPV, so a brief ridge dragging colder uppers may pop up or be modelled but at the range of post-D8, of little confidence.

Good news IMBY the weather will be average to mild and little rain and no storms. For London, the next 8 days 850s and 2m temps:

 

[Lukesluckybunch]

North South divide day 10 ecm..snow or snow showers into Scotland and northern England potentially..mild in the south

[northwestsnow]

EC day 10 and the million dollar question remains is the colder air to the North going make it across the UK before Spring ??

 

[Lukesluckybunch]

7 minutes ago, northwestsnow said:

EC day 10 and the million dollar question remains is the colder air to the North going make it across the UK before Spring ??

 

Looking at that chart,I would say no!even some of the long rangers aren't confident if or when the colder air arrives in february!

Edited January 28 by Lukesluckybunch
Adding

[Dennis]

newest BOMM MJO 

[jules216]

I am throwing the towel in with this winter already. Actually I ve been quite convinced about it for good few weeks and posted here before that February would be very much different then the donkey carrot seasonal models. I am trying to mentaly get ready for these stupid northerlies that will by no doubt again arrive in spring and ruin my fruit crops at bloom like it does every spring since 2019. Its the same thing all over again actually. If I think back that any reasonable okay winters since 2014 came after not so hot but changeable summers -2016,2020. So a writing was on the wall after hot summer 2023.

The seasonal models like ECMWF and UKMO for february are just a joke. Meteogram this morning for my location is like late March 

[daz_4]

  @jules216 Yep, it is going to be a struggle to get something of note apart from higher elevations even here in Central Europe. Even the "better" GFS runs have zero ice days and not that much snow. Not that I mind, I like winters less and less due to the fact how they changed but I sure hope that we will get a warm spring for once. Those northerlies in spring have been pain the ass for the past few years.

[nick sussex]

Not the most exciting starts to the day .

The GFS has dropped its more interesting output from yesterday . 

The ECM brings the jet further south but struggles to get the cold air to clear the UK .

The GEM has zero interest until day ten where it teases with a possible high developing to the ne.

The UKMO at day 7 probably the best in terms of cold prospects at that stage but it rarely picks out a colder option at that timeframe which trumps the others .

I think it’s best to reserve judgement on future prospects for a while yet . 

The MJO is still on the move into phase 7 . And there is a timelag with that.

 

Edited January 28 by nick sussex

[jamesthemonkeh]

The CFSv2 remains bullish on a high pressure anomoly to our west for February, though it has trended it a little further east in recent days.  A drier than normal month seems likely.

Does anyone have any thoughts as to whether our "reflective SSW" could still have impacts on our weather in March/April (assuming no further warming events) and whether we could still end up with high pressure further north?  It seems to me that previous SSW events increased northern blocking in the following months, and not only after the immediate impact - ie also April/May 2018.

[Mike Poole]

ECM clusters T192-T240:

Zonal on cluster 1, weak ridge in the Atlantic on clusters 2 and 3, but nothing very substantial.  

T264+:

I think the trend in this timeframe that is clear, is a trough developing in Europe to our SE on both clusters here.  However, the signal for high heights to the NW to go along with that is much less clear now.  There is no consistent sign of a big Greenland high, and the signal on the 46 for height rises to our NW is weak at best - but given the trough to the SE, it may be that well placed wedges could work very well, cluster 2 suggesting something like this, but such features will not be apparent until much much closer to T0.  So I think we are headed towards a period of potential for colder weather, but the detail for that is some way away.  

[feb1991blizzard]

  @nick sussex

I think its been a very exciting start to the day, plenty of activity below the -5c line on eps, also an MJO chart into 8 - excellent   @Dennis  - albeit low amplitude.

[phil nw.]

I haven't posted much recently as the modeling continues to remain uninspiring in the short term.

There are some signs of a pattern change in week 2 with height anomalies appearing in the Atlantic in the ensembles but the Euro heights remain stubbornly present, maybe a little move west with time.

Zonal winds remain relatively strong at 10hPa but lower down there is a forecasted weakening and depending on some help from the mjo may provide something colder as we head beyond day 10.

[Dennis]

  @feb1991blizzard

i like the Korean version 

[Dennis]

  @Mike Poole

....There is no consistent sign of a big Greenland high

Thats just the most strangest on what i see in other parameters who highlight the GH , by AO block

so what is here going on by EC ?  I think they wait to change after the weekend .....

[Chesil View]

The background signals continue to suggest that another set of cold synoptics as we move through the second half of meteorological winter is a reasonable assumption but if it materialises at all it looks like it will be a slow and steady process possibly with more than one bite at the cherry to get there. Which will do nothing for the  nervous dispositions of our more impatient members

The late winter prospects are definitely not in Amazon mode at the moment and certainly not prime.  

Edited January 28 by Chesil View

[Dennis]

i will see an orkan here to norway wed-thurday 935Hpa vortexlobe

Edited January 28 by Dennis

[Battleground Snow]

Jff but a slider snow event at day 9.

 

[Pembroke Dangler]

4 minutes ago, Battleground Snow said:

Jff but a slider snow event at day 9.

It then transitions to a decent northerly but as you say JFF would be great if that’s how it happens. 

[MJB]

I think this is the least we deserve LOL .............................if only eh?

[feb1991blizzard]

  @Battleground Snow

You know what analogue fits that chart don't you?