Model Output Discussion - Spring Has Sprung

[Lukesluckybunch]

A bit more like it from the ecm..snow showers showing up!

 

[Uncertainty]

Stunning chart!

[Frigid]

 Uncertainty First BOOM chart since mid Jan. Of course we start to see eye candy as soon as winter ends lol

[Lukesluckybunch]

10 minutes ago, Uncertainty said:

Stunning chart!

Snow showers in the north there..threat of more persistent snow in the South I think..

[Jacob]

 Lukesluckybunch not for the south with those -4 uppers

[feb1991blizzard]

 Jacob

more reinforcement soon after though with colder uppers.

[Anthony Burden]

Evening all,ECM firming up on this northern blocking with low pressure to the south feeding in this progressively colder easterly feed.March looking more and more wintery with the effects of the major SSW showing it’s hand nothing would surprise me regarding this coming month including the white stuff.

[Lukesluckybunch]

3 minutes ago, Jacob said:

not for the south with those -4 uppers

It's actually -6/8 uppers

[Mike Poole]

 nick sussex Yes, the ECM is out of the same stable as yesterday’s GEM 12z.  

Would need some luck to land that - the thing is though, the winter cold-synoptics shield is switched off now, so at least we are in a fair game.  Sadly, I never feel we are in a fair game when such things show themselves on the model output in January.   

Edited February 29 by Mike Poole

[stodge]

Evening all

Well, it's good to have some interesting synoptics in March (and not unusual in all honesty).

The journey from the weekend seems to be settling - the LP sends enough energy back west into the Atlantic to spin another vigorous little LP towards the south west on Monday but and we might get a brief S'ly flow midweek but the Scandinavian HP intensifies and the LP begins to disrupt south leaving the British Isles in a SE'ly or ESE'ly flow by the end of next week.

Plenty of hints in FI we could get a more E'ly flow but nowhere near the reliable currently. 

The European warming continues to feature strongly on the 10 HPA charts - it's unusual to my eye but likely to keep the synoptic interest going.

 

[jellybaby1969]

 andymusic

 

I hope so for you guys !

[Mark wheeler]

Blimey the fat lady isn't quite singing yet . 

[Tim Bland]

Day 10 has potential I suppose

[IDO]

EC is off on one this evening with a whopper of an outlier. For London, the ens:

There is nominal hope of verifying that!

[damianslaw]

ECM going for a cold easterly, backing the trough far west. UKMO heading in the same direction. GFS going with a similiar evolution but doesn't quite pull in the cold easterly instead heights sink through the UK.

A change to something very different on the way, heights building strong to our east. Question is whether low heights disrupt and undercut cleanly to allow a long fetch easterly draw, or hold in situ to our west, enabling a milder SE draw.

First half of March with a long draw easterly certainly not late in the season to deliver wintry goods.

[Methuselah]

 damianslaw Cold as in blizzards, or cold as in merely boring and uncomfortable?

[stodge]

 IDO Tonight's party-pooper.

After last night's GEM 12Z OP, it is interesting to see the evolution even on the table let alone from the OP run. 

As with last night's GEM, the key to the evolution is having the Scandinavian HP even further north which pulls the very cold air over from NW Russia though the airmass itself is of Arctic origin. The cold airmass flows WSW over Scandinavia and phases with the energy over southern Britain.

[IDO]

 stodge

The D10 op versus the mean from the EC are very different:

  

The GEM and GFS means:

They are solid means from the three suggesting a high level of certainty, so random ops that show otherwise, that are massive outliers and disappear by the next run (e.g. GEM) are best treated with sceptisism.

[Uncertainty]

@IDOyou’re absolutely right mate. A se flow, potentially more low pressure dominated than high does seem the form horse on the means. Only reason I wouldn’t rule out something akin to the ec op is the big reversal plus, of course, the irony of avoiding cold Synoptics till after winters finishes. 
 

The op cluster has 8 members so less than 20%. I actually think that’s about right for the probability of a cold long fetch easterly amidst a -15m/s protracted reversal / potentially unfavourable mjo phase. 

[damianslaw]

 Methuselah Depends if the draw is long fetch from Russia, then cold and wintry, but may just be a raw chill cloudy SE flow with near average temps.

[stodge]

 IDO I'm much less convinced by "certainty" at Day 10 than I would be certainty at Day 4.

This winter has been a fine example of the best laid plans of Day 10 forecasts not surviving to the "reliable". 

Let's see where we are this time next week.

[Methuselah]

 damianslaw I'll HOPE for the former but expect the latter. 

[Kirkcaldy Weather]

Wanted to add some info for the setup as we start Spring and some focal areas I'm monitoring heading through the first 2-3 weeks of March.

During the first area of precip during the overnight hours tonight into tomorrow morning a tornado can't be ruled out as there will be an increased amount of shear and SRH values are also higher.

Wales moving East Northeast across a large part of England.

As this activity develops into frontal precip moving northwestward into Scotland there will be a zone of increasing instability from Southwest England pushing into Central and Southeast England from mid day tomorrow. Thundery showers development with thundersnow also possible.

This can be noted as increasingly cold cloud tops move through.

My main period of interest continues to be through week 2 of March and in particular by mid March with a number of intriguing prospects.

Fitting with the MJO compisites in my post above we are beginning to see the feedback of the next opportunity for a possible snowy system into Northeast America with this currently looking to be devdloping around March 8th - 11th though not a huge emphasis on precise dates.

During this timeframe we also see current trends which move the Tropospheric Vortex more into our side of the Northern Hemisphere.

Into Mid March this will be part of the main 500hpa setups with our retrograding block moving into Greenland which gradually continues westwards as this is a big part of the El Ninò pattern as I showed prior, main focal points will be how strong we get into the negative NAO plus the energetic connection with the cyclone from Northeast US into our current UK trough which moves into the Atlantic as discussed plus as these join and link to the emerging trough toward Scandinavia ie the Tropospheric Vortex.

[Rain All Night]

8 hours ago, Rain All Night said:

0z/6z ensemble means, out to Thu 15th (day 15)

I'm looking at the ensemble means in a slightly more pessimistic light this morning; it's possible we (or at least, most of us) might only see a few dry days from the 6th before the Atlantic trough lodges itself to our southwest and causes misery to those not sufficiently far away from it.

Perhaps more members late in these runs suggesting that there will be a loss of amplification towards mid-March, though that is less apparent on the GEFS.

0z/6z deterministic runs, on Thu 7th (day 7)

As with last night, ECM and ICON still the most appealing to my tastes.

 

12z ensemble means, out to Thu 15th (day 15)

The ECM and GEFS means generally suggesting the Atlantic failing to take back control after 6th/7th March, but still sitting close enough to interfere at times (GEFS more earlier on, ECM more later on).

12z deterministic runs, on Thu 7th (day 7)

Seems likely it will be dry for most or all of us on this day next week. Hallelujah.

[phil nw.]

I think any easterly would need to hold for a number of days to see any meaningful cold pool from the east.

We have to remember Eastern Europe is currently Anomalously warm so we would need a long fetch airstream from Russia and it's asking a lot this time of year to get a snowy setup .

We need the high to be oriented west to east and this is something yet to be established in the model runs.

Our best bet now would be a high towards Iceland or Greenland with a north easterly Continental Arctic sourced flow down through Scandinavia.

It's worth sticking with the next few model runs to see what transpires but I think we are in the last chance saloon now for coldies to see any chance of widespread lying snow.