The hunt for cold - Model discussion (late November)

[Mucka]

UKMO has a very healthy looking Arctic high at day 7

Ideally it would be better placed nearer to us but not complaining.

GFS for the same period still wants to stubbornly build pressure to our South. Uninspiring run it has to be said.

 

ICON builds a formidable block to the East, just needs an Atlantic ridge to slam the door on the Atlantic.

Edited November 27, 2018 by Mucka

[Mucka]

GFS parallel 144 better than GFS 00z Op

[ArHu3]

7 hours ago, bluearmy said:

Nothing obvious on the ec46 out to week 5 to raise the excitement of the coldies .......

How consistent is ec46 in your opinion?  Did it pick up on the extreme heat in summer? 

Edited November 27, 2018 by ArHu3

[booferking]

6 minutes ago, Mucka said:

GFS parallel 144 better than GFS 00z Op

Gefs have took a clear step away from blocking the majority are zonally from start to finish low after low I'm afraid..

[Mucka]

3 minutes ago, booferking said:

Gefs have took a clear step away from blocking the majority are zonally from start to finish low after low I'm afraid..

Not too worried about that at the moment as I feel the signal for blocking is pretty strong still overall but it would be nice to see them trending toward blocking.

It is fair to say there is no cold signal as of yet though but I guess that can't really come until the ensembles get to grips with the blocking should it happen.

I'm not convinced either way as far as cold tbh though I do expect at least mid lat blocking to form near end 1st week Dec and a pattern change from zonal.

Time will tell.

 

 

 

 

[northwestsnow]

 

8 minutes ago, Mucka said:

Not too worried about that at the moment as I feel the signal for blocking is pretty strong still overall but it would be nice to see them trending toward blocking.

It is fair to say there is no cold signal as of yet though but I guess that can't really come until the ensembles get to grips with the blocking should it happen.

I'm not convinced either way as far as cold tbh though I do expect at least mid lat blocking to form near end 1st week Dec and a pattern change from zonal.

Time will tell.

 

 

 

 

Lets just say i'm glad its only the 27th of November Mucka because the NWP seems to be going from bad to worse at the moment.

Ive been around long enough to know things can change quite quickly but at this juncture i'm getting a feeling of deja vu in so far as Decembers pattern is concerned.

On a slightly more positive note BBC RAW data which i think is derived from mogreps is going for settling down from the 5th of Dec .

Edited November 27, 2018 by northwestsnow

[feb1991blizzard]

19 minutes ago, northwestsnow said:

 

Lets just say i'm glad its only the 27th of November Mucka because the NWP seems to be going from bad to worse at the moment.

Ive been around long enough to know things can change quite quickly but at this juncture i'm getting a feeling of deja vu in so far as Decembers pattern is concerned.

On a slightly more positive note BBC RAW data which i think is derived from mogreps is going for settling down from the 5th of Dec .

on the whole i agree although 0z para decent.

[booferking]

31 minutes ago, northwestsnow said:

 

Lets just say i'm glad its only the 27th of November Mucka because the NWP seems to be going from bad to worse at the moment.

Ive been around long enough to know things can change quite quickly but at this juncture i'm getting a feeling of deja vu in so far as Decembers pattern is concerned.

On a slightly more positive note BBC RAW data which i think is derived from mogreps is going for settling down from the 5th of Dec .

Deja Vu i can concur para v what happen last week

 

Edited November 27, 2018 by booferking

[Seasonality]

The model rollercoaster is going full steam I see 

[NO LONGER POSTING]

Exactly what was said by more experienced people yesterday is happening.. 

The models are throwing out Milder options but also colder options GFS has done this exact thing on it's last 3 model runs in FI.

Im not expecting December to be cold or Snowy... It never is.. Apart from the exceptions.. In my short 24 years on this planet ive learnt not to bother myself getting hung up on what happens in December and even let that dictate the rest of winter... Where we sit allows us to flip Milder or colder within a few days/weeks without warning 

It's very easy to go from "OMG" when the GFS churns out FI stuff like the 18z and 12z yesterday to then be like "oh fk sake" when the 00z comes out.. Its a computer it is randomly creating a scenario each time until the reliable where it firms up. Even then we get some surprises right within the 24-48 hour period!

Until a raging Westerly is showing at the start of April Im enjoying the ride so far.. 

 

[Weathizard]

Vortex setting up just where we want it on the ECM... not! Iberian heights also prominent 

[feb1991blizzard]

That ECM from yesterday with that trans-Arctic-ridging seems to have disappeared and its gone back to usual today.

[northwestsnow]

4 minutes ago, feb1991blizzard said:

That ECM from yesterday with that trans-Arctic-ridging seems to have disappeared and its gone back to usual today.

Like i said, NWP going from bad to worse if its dry or cold you want.

..

[bluearmy]

1 hour ago, ArHu3 said:

How consistent is ec46 in your opinion?  Did it pick up on the extreme heat in summer? 

the mean (which we see) is fairly consistent beyond week 4 as it generally tends to climatology ........ I usually take note of week 3 (which has some possibilities) and week 4 (which doesn’t though the clusters could be anticyclonic across us) 

just a part of the puzzle 

[ArHu3]

9 hours ago, Daniel Smith said:

Strat Vortex was the strongest in recorded history for the time of year at one point, still no downwelling..

Largely thanks to continued heat flux from the Troposphere up into the Strat

Last year? Last year it was record week until it picked up strength mid to late December 

[jules216]

From my perspective it's all about learning something new every season. I remember back in 2011 when @Glacier Point did Netweather winter forecast and he mentioned that seasonal forecasts are like A+B+C = D - forecast. If one presumption doesn't happen according to it then whole forecast will most likely be more wrong then right.

For example which teleconnection drives weather on our  side of Atlantic in western Europe mostly: is it tropical forcing(MJO),low solar,stratosphere, or SST? We know some are conductive to blocking and some are not this year. Looking at MJO and forecast from NOAA yesterday they are anticipating robust event through phases 8 to 3. If we look at re-analysis of phases 8 and 1 they show blocking and cold singal in Europe generally. Zonal winds also do not look like interfering much over the coming weeks as they might even trend below average. 

So in my view if this mornings GFS and ECMWF deterministic outputs pan out correctly then MJO presumption will be wrong as they do not show HLB, barely MLB. 

After this I personally would consider not favorable SST as most important driver for our weather, where the Atlantic energy coming from eastern CONUS takes over with lows spinning across sometimes cut off sometimes part of vortex that loves staying between Greenland and Hudson bay. 

[Tim Bland]

Ensembles are a bit disappointing. Massive uncertainty after day 6 but inwouod like to see more cold options. 

[Met4Cast]

22 minutes ago, Tim Bland said:

Ensembles are a bit disappointing. Massive uncertainty after day 6 but inwouod like to see more cold options. 

Give it time - The period of interest isn’t in range yet

[KTtom]

To be honest the whole output is dissaponting at the moment. I invested in outside lights this year for the run up to Christmas based on the Mets predictions of a dry settled spell from early December.. now it's looking like a transient area of high pressure before the wind and rain returns for Christmas. Currently looking like a bulk standard December on the way...help from the strat needed again this year?

[carinthian]

Morning all , -4C in the village and snow cannons back in operation on the slopes. Due to open runs this weekend. Picture over looking Katschberg village. Another variation on the model runs this morning but the theme towards a rise in pressure over the British Isles likely in the period day 7 to 10. So a fairly short lived spell of unsettled and relatively mild conditions in your part of the world , although not particularly mild so in the north. The model our expert use still indicate a strong developing ridge over the British Isles for the second week of December and pressure falls in Eastern Europe as the trough starts to sharpen against the cold block. The forecast 300mb flow is indictive of this process over Scandinavia and into East Europe in the longer term charts . 

C

 

Edited November 27, 2018 by carinthian

[Met4Cast]

20 minutes ago, KTtom said:

To be honest the whole output is dissaponting at the moment. I invested in outside lights this year for the run up to Christmas based on the Mets predictions of a dry settled spell from early December.. now it's looking like a transient area of high pressure before the wind and rain returns for Christmas. Currently looking like a bulk standard December on the way...help from the strat needed again this year?

Based on what?

Last nights models had sub -8c over much of the UK, the models this morning now show mild, sure. But that’s what I and others have stated would happen, wild swings in the models were expected by a few of us on here and that’s whats happening.

Further flip flopping from mild/cold/mild is expected whilst the models deal with the evolving forecast. GEFS ensemble mean as high pressure moving Northwards from Iberia across the UK, look at the Eastern Hemisphere across the Arctic, also filling up with high pressure 

EPS mean similar, high pressure filling the Arctic

Extended EPS shows the Atlantic trough that’ll be with us this week backing out West with a signal for heights to build across Scandi day 15

Certainly far, far from “bog standard”.

Continued flip flopping expected but note the likelihood of increasing cold runs towards the end with milder runs becoming fewer and farther between as this week progresses and into next week. 

The Strat isn’t an issue. There is no downwelling, it’s not influencing our weather at the moment. Sig wave 1 activity continuing with further Heat Flux into the Strat from the Trop in the forecast, the Strat is very much under attack from a couple of different angles right now. The expected developing Scandi Ridge/Arctic High into Dec could be the nail in the coffin anyway.

15-20th December < That’s the timeframe for the pattern switch.

Edited November 27, 2018 by Daniel Smith

[blizzard81]

2 hours ago, Weathizard said:

Vortex setting up just where we want it on the ECM... not! Iberian heights also prominent 

The last few ecm op runs have taken the main chunk of the pv to the Canadian side. Not good for us. Especially when the Siberian high is acting like a hermit. 

[Paul_1978]

3 hours ago, booferking said:

Gefs have took a clear step away from blocking the majority are zonally from start to finish low after low I'm afraid..

Completely different from 6 hours previously then when we were advised of the complete opposite! So much inconsistency I don’t know what to think. 

Best to take a step back and look at the bigger picture methinks. Personally I’m keeping an eye on all the strat warming talk as that would be a game changer. 

[Newberryone]

A case of spot the difference with regards to day number one and day 10 on the Ecm overnight run. Atlantic influence still very evident out to day 10, at least, with north western areas more prone yet again to any wind and rain. Still, as the more knowledgeable in here have already stressed the timeframe of interest with regards to cold weather prospects is from mid-dec onwards. Let's just pray they're bang on the money with this theory...

[KTtom]

11 minutes ago, Daniel Smith said:

Based on what?

15-20th December < That’s the timeframe for the pattern switch.

Overnight model runs, EC46, BBC forecast, Met forecast, ENS....not much really