Model output discussion - The Hunt For Cold

[SLEETY]

So Nice to approaching winter with some decent looking cold weather sypnotics on the horizon.Usually its a raging Atlantic with low pressure over iceland and high pressure to the South.

That SSW at end of Feb has really changed the weather this year we seem to have gone Continental.

[northwestsnow]

Who would have dreamt it? The hunt for cold is ON!!

Lovely GFS00z with northern blocking galore!!!

Scandy high in all its glory this morning ..:-)

[Weather-history]

How often do you see a mean 240hr chart like this?

4 month in the row where the month's CET drops during the final third of the month?

[Weather-history]

Got to favour that overall, that autumn 2018 will be drier than average for a lot of the country

 

[Met4Cast]

Ka-Boom.

Game on.

[Radiating Dendrite]

Looks great, but it is still in mid-range / FI. How often have we seen a shortwave pop up once we get to the higher resolution timeframes and scupper our chances. 

This does have a whiff of 2010 though, the models locked on the target and never really deviated. 

[cyclonic happiness]

So does this mean we could be cold by the weekend, but initially under an inversion?

I need to know this so we can winterise the nursery and garden centre, to stop the pipes from freezing 

[Met4Cast]

Model support from all three of the big players, GFS, ECM and UKMO

Solid ECM clusters from last night, too

It does feel as if the models are locking onto this signal now, they're all running with it and the building blocks are moving into the reliable.

[daz_4]

The question is where exactly will that initial weak easterly go. ECM and GFS para push the cold air to SE Europe.

[BLAST FROM THE PAST]

8 hours ago, Mr Brown said:

I know it may be early to ask but, what is your forecast for the month of December as a whole? 

Not at all, cold start to winter, snow early on and Very notable period over Xmas.

 

The hint has been coming but this morning the models are doing something in the nigh on reliable (T120) and balloooning that HP up over Scandi to then bring an easterly flow.  This is looking good....but we just need T72 now

 

BFTP

Edited November 12, 2018 by BLAST FROM THE PAST

[markw2680]

With all these lovely charts starting to appear for the end of the month I have to ask where is nick Sussex? Although I’m hoping for no shortwave dramas this time around.

in all seriousness I like reading his posts so would be a great comeback mate

[BLAST FROM THE PAST]

1 hour ago, northwestsnow said:

Who would have dreamt it? The hunt for cold is ON!!

Lovely GFS00z with northern blocking galore!!!

Scandy high in all its glory this morning ..:-)

RJS, Steve Murr, I think I had an hallucination too at some point.  Just want it t72 now

 

BFTP

[Ali1977]

A huge block is good for dry weather but unless it migrated North enough to pick up a colder Easterly feed from Scandy or Siberia nothing much snow or freeze wise with materialise this early in the year. Scandy isn’t that cold just yet so we’d need a long Easterly feed, which actually looks possible with the latest charts.

Whats is nice to see is the lack of any PV building up, if that stays at bay any HP has a better chance of getting in the right place, and we know late Nov can deliver severe winter weather if all falls into place.

[Summer Sun]

We should begin to see increasing amounts of frost and fog in the coming days as high pressure begins to dominate 

Where cloud and or fog lingers it will be feeling rather chilly

[shaky]

7 minutes ago, Summer Sun said:

We should begin to see increasing amounts of frost and fog in the coming days as high pressure begins to dominate 

Where cloud and or fog lingers it will be feeling rather chilly

Could you post the gfs upper temps for same time please!!am sure they are a lot colder at that level!!

[Summer Sun]

2 minutes ago, shaky said:

Could you post the gfs upper temps for same time please!!am sure they are a lot colder at that level!!

Initially, they're not overly low at face value again frost and fog would make it cooler

later they go colder as GFS has an easterly feed whereas ECM is more SE'ly

[ICE COLD]

GEFS 00z ensembles are looking very nice again this morning. Snow row on the up . 

[Leo97t]

First ensembles showing ice days in London if I'm not wrong

[Geordiesnow]

35 minutes ago, Summer Sun said:

We should begin to see increasing amounts of frost and fog in the coming days as high pressure begins to dominate 

Where cloud and or fog lingers it will be feeling rather chilly

I don't think frost will be an issue at this moment in time in all honesty, with such high upper air temps dewpoints are not going to be all that low and the models are hinting the winds will pick up during the weekend so whilst the dewpoints will lower somewhat with stronger winds then fog might not be an issue either. Also as winds swich more to a SE'ly, drier air may prohibit fog formation anyways.

Some really impressive thicknesses showing on the ECM model which indicates a very strong block but would prefer if it was further Northwards and Westwards in an indeal world.

[ItNeverSnowsInWindsor]

7 minutes ago, Geordiesnow said:

I don't think frost will be an issue at this moment in time in all honesty, with such high upper air temps dewpoints are not going to be all that low and the models are hinting the winds will pick up during the weekend so whilst the dewpoints will lower somewhat with stronger winds then fog might not be an issue either. Also as winds swich more to a SE'ly, drier air may prohibit fog formation anyways.

Some really impressive thicknesses showing on the ECM model which indicates a very strong block but would prefer if it was further Northwards and Westwards in an indeal world.

Yes, just hope the ECM op is one of the warmer members in its ensembles suite.

Edited November 12, 2018 by prolongedSnowLover

[nick sussex]

1 hour ago, markw2680 said:

With all these lovely charts starting to appear for the end of the month I have to ask where is nick Sussex? Although I’m hoping for no shortwave dramas this time around.

in all seriousness I like reading his posts so would be a great comeback mate

OMG you must be psychic ! Had quite a few visitors over so not been on for a while but I’m back now and it looks like a good time given the models !

It looks much better for the UK now after some pretty awful weather , and we’re back to chasing cold pools around .

Quite a difference between the ECM and the GFS. Even without the cold pool temps are set to lower near the ground even though on the ECM 850 temps are nothing to write home about .

Next few runs key to see whether the ECM starts cutting the jet back in towards the UK . Overall though given recent conditions a return of high pressure I’m sure is welcome .

[Methuselah]

Just so as to prove that I'm not entirely living in the 1960s, here's the latest GFS T+384 operational:

Just a hint of a straight northerly, should the HP shift into the Atlantic, so a massive European cool-down is looking ever more 'certain'...

[biggreyface]

With all those lovely charts starting to appear for the end of the month I have to ask where is frosty? 

Come on Carl it’s time to give up the heat and sunshine in the Caribbean and return to good old Blighty

[carinthian]

On ‎11‎/‎11‎/‎2018 at 07:46, carinthian said:

Yes, think UKMO looks the most robust of the models to strengthen the high pressure ridge over the British Isles by next weekend. In the meantime, plenty of warm air advection help this process with some very mild temps by Thurs/ Friday before colder surface starts to take affect. Sometimes this process can speed up just as we have seen in recent runs. Think GFS model is still uncertain regarding its 300mb jet projection in the latter stage of the runs, hence its variations of high pressure placement in its 6 hourly runs. The UKMO looks like it is going to retrogress the high NW wards. More runs needed. Back tomorrow with thoughts of our own team .

Morning all, as promised a bit of an update from over here. Short term, rock solid with UKMO at 144t. Mildest day still looks like Thursday .Stunning over here at the moment with mild sunny days unless you are stuck under the temperature inversion in the valley. Deterministic Forecasts for the medium long term have advanced the high pressure cell centre to be between Northern Britain and Southern Scandinavia for the early part of next week. The single model still showing strong retrogressive features towards the end of the month with a probability forecast of 50/60 % ( not sure what MOGREPS ) medium range showing but suspect something similar based on their earlier outputs. Sometimes, a slow burner as in this case advances changes at bit quicker than being shown 3  days or so ago and the situation becomes more fluid. Still height falls over Europe after day 10 with a backing of the wind flow still showing up with increasing chance of Polar Continental airmass getting into parts of Europe and even a outside chance of a quicker route to cold over the British Isles with Arctic Maritime flow possible. However, we are sometime away yet but the encouraging features maintaining a  split jet will help to a colder scenario. Also nice to see fairly solid agreement in the main models.

C

Edited November 12, 2018 by carinthian

[Ali1977]

Gloesea has flipped cold for winter, nice to see.