Model output discussion - 16th Nov onwards

[dragan]

Certainly looks like an unsettled cool period coming up, temps about average.

[knocker]

The gfs again a very unsettled run with some quite wintry weather, particularly in the north, as depressions run east on a very strong jet. The south escapes the worst with the periodic proximity of the HP to the SW. Later in the run the lows duck SE over central Europe under the influence of the high pressure to the NE/E and so the run ends with this scenario and a ridge over the UK and a disrupted Atlantic flow.

Charts courtesy weatherbell

Edited November 21, 2015 by knocker

[dragan]

Alas knocks, the ski resorts up north will be laughing

[Polar Maritime]

The GFS continues this morning to show a very unsettled/stormy and cold start to Winter, As depressions spin in off the North Atlantic from the N/W on a Pm flow dragging in cold air with them. As i said the other day, Perfect synoptic's for blizzards in the North.

 

On a side note - After all the so called 'upgrades/downgrades' over the past few days, Last night delivered snowfall for many areas, With lying snow here this morning it just goes to show how fickle these set-ups are.

Edited November 21, 2015 by Polar Maritime

[knocker]

The ecm tends to more amplification of the HP to the SW but towards the end swings a deep depression NE and develops a little system in it's southern quadrant which nips west across England

 

 

The GFS continues this morning to show a very unsettled/stormy and cold start to Winter, As depressions spin in off the North Atlantic from the N/W on a Pm flow dragging in cold air with them. As i said the other day, Perfect synoptic's for blizzards in the North.

 

On a side note - After all the so called 'upgrades/downgrades' over the past few days, Last night delivered snowfall for many areas, With lying snow here this morning it just goes to show how fickle these set-ups are.

 

And didn't forecast the Pembroke Dangler down here this morning PM. Quite foul

 

The Dangler

[Frosty.]

The Gfs 00z shows generally below average temperatures, only occasionally struggling up to average in the south and it's a very unsettled run with wintry ppn for northern hills  / mountains and frosty nights in the quieter interludes, especially by the end of the run...a much more seasonal weather pattern with a generally nw / se aligned jet...and our first wintry blast is here!!       

Edited November 21, 2015 by Frosty.

[Polar Maritime]

ECMWF also looking very similar to the GFS for the turn of the Month.

Edited November 21, 2015 by Polar Maritime

[Frosty.]

Yes this is much more seasonal from the Ecm / Gfs 00z with frequent Pm incursions bringing wintry ppn in particular to northern hills, I hate mild mush, this is much better.

[East_England_Stormchaser91]

End of the 00z would be on the cusp of something magic. Europe would certainly be heading for some brutal cold if that came off! 

This current cold snap was spotted quite a way off too albeit slightly watered down nearer the time. We can only hope!

[John Badrick]

Yes this is much more seasonal from the Ecm / Gfs 00z with frequent Pm incursions bringing wintry ppn in particular to northern hills, I hate mild mush, this is much better.

 When was the last time (if anyone can recall) we had a good dumping of snow to lower levels down south i.e Cornwall and Devon from a PM source

[Iceaxecrampon]

Massive Greeny - Icelandic LP forming at T+123 (Thursday 26th)

 

 

Filling and sinking SW for next Saturday.

 

 

Saturday potential

 

 

......Sunday

 

 

 

 

 

 

 

 

 

 

Edited November 21, 2015 by Iceaxecrampon

[Iceaxecrampon]

Yes this is much more seasonal from the Ecm / Gfs 00z with frequent Pm incursions bringing wintry ppn in particular to northern hills, I hate mild mush, this is much better.

 

Nice December 1st "Advent" Chart Frosty - too far off but next weekend reload looks promising.

[johnholmes]

The anomaly charts do not suggest any deep cold but with a flow n of west, just, then it is not going to be mild overall, unsettled also with the strength of the predicted flow at 500mb. Link below to ECMWF-GFS both of which are not totally unlike NOAA last evening but have a stronger flow and the trough into Europe is much more marked.

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

not a bad outlook 6-10 days for the Alps ski resorts.

[Northern Sky]

Both the GFS and the ECM show quite a potent blast of pm air around t168. Of course usually the models over estimate the coldness of the 850's but I'm sure there have been times when a truly cold zonality delivered snow for many. I think I remember someone posting some historical charts illustrating true cold zonality but I can't remember what year they used as an example.

 

Anyway, cold wind and rain is great too.

[Frosty.]

Nice December 1st "Advent" Chart Frosty - too far off but next weekend reload looks promising.

Yes it's a lot more promising than if we had a long draw swly flow or a very mild limpet euro high slug across the uk, at least it's seasonal now which could lead to something more wintry further down the line as we are now experiencing.

Edited November 21, 2015 by Frosty.

[Northernlights]

Both the GFS and the ECM show quite a potent blast of pm air around t168. Of course usually the models over estimate the coldness of the 850's but I'm sure there have been times when a truly cold zonality delivered snow for many. I think I remember someone posting some historical charts illustrating true cold zonality but I can't remember what year they used as an example.

 

Anyway, cold wind and rain is great too.

Possibly December 1973  a few days before Christmas? We were blocked in with exceptionally heavy snow and wind.

[BLAST FROM THE PAST]

Quite a timely post BFTP

 

GFS 00z has a robust Siberian high which forces the trough disrupt and dig South

 

 

We will need that Siberian high in place though for anything more than a snow on hills PM waft here and there.

Indeed Mucka nice to see the models support the overall outlook.  The runs show quite a lot of cold pM air to flood and always be close by to the UK.  I believe this is right and again there will be snow for many over the next two weeks....but as ever in pM air especially on lower levels its short lived.  Very seasonal though to say the least.

I mentioned the Siberain HP will play its part in early winter even if it was to help hold the trough in a favourable place to allow pM air to flood thE UK with some potent blasts.

Nice to see that the warm sectors that were shown to shunt the colder air away have been minimalized this morning...again I think that's right...less cold then more potent pM air.  Very good runs this morning and may they continue.  I feel what we see this morning is the right direction

 

BFTP

Edited November 21, 2015 by BLAST FROM THE PAST

[bluearmy]

Day 10 ECM and gefsp on the same page at day 10. Flat w euro high anomoly returning as the Atlantic fires up.

Gefs and gefsp looked quite different by day 16, especially over the polar field. Extended ECM has large stretched polar vortex by end week two with two centres - nw Greenland and kamkatchka. tbh, you could argue that the ECM isn't too far from being split by the combo of Alaskan ridge and Siberian high anomoly. Same is true of the GFSP. those gfs op runs developing blocking to our North are not without support then.

Edited November 21, 2015 by bluearmy

[SMU]

Add to the above 4 out of the 50 ECM ensembles have maxima at 0c or below for debilt at day 15

Thats nearly 10% in old money !

Its a start

[Neilsouth]

Why yet again, does the cold pool keep situating itself over NE states and Canada? Or is it in a completely different place to last year? Can someone compare Cheers 

 

Oh and good morning

[Frosty.]

The Gfs 6z op run shows frequent polar maritime incursions and the run ends with an Arctic blast. Once again it looks like a very unsettled, occasionally stormy & seasonal outlook with plenty of snow on northern hills / mountains and occasionally to lower levels and further south, in the quieter interludes there are widespread frosts and any milder weather is fleeting.     

[kag]

Mid February 1973. Ayr had more than 10cm of powder snow from a PM incursion which in my memory in coastal Ayrshire has not been matched. interesting if someone could find a chart for this?(Jan 84 similar )

[Coopsy]

Mid February 1973. Ayr had more than 10cm of powder snow from a PM incursion which in my memory in coastal Ayrshire has not been matched. interesting if someone could find a chart for this?(Jan 84 similar )

 

Feb 15/1973....

 

 

Jan 15/1984...

 

 

 

Edited November 21, 2015 by Nemesis

[damianslaw]

Models showing a a meridional jet with the longwave trough and low heights digging well into central/southern Europe - thus preventing the build up of robust central based euro heights, instead we look like maintaining a predominantly west/northwest airflow with alterations between PM and RPM air.

 

So an unsettled outlook with temps overall close to the late Nov mean, with high likelihood of substantial snow down to modest levels in the north, with frost in clearer spells, the south drier and brighter.

 

A very typical late Nov set up.

[Mucka]

GFS, if it is good for one thing, it is picking up long range signals for potential blocking.

As such there is just the slightest signal for Atlantic/Greenland blocking to try again somewhere into 2nd week of December.

ECM has surprisingly been more progressive than GFS of late with pushing away any Siberian high influence but if we can get a stronger more influential high as with GFS then a response to that could be a deeper trough into Europe and said Atlantic height rises.

 

Crystal ball territory at the moment but worth keeping an eye on for coldies over the coming week to see if the idea gains any traction.

Edited November 21, 2015 by Mucka