Model output discussion - 1st December onwards

[knocker]

 

A brief overview of the latest EC32 update

The anomaly on the 13th LP Alaska, with ridge into GOA,  and SW US with HP NE Canada, A trough NE Atlantic and eastern Europe. So mostly unsettled but tending towards a N/S split.

The next week up the 20th initially brings an intensification of the trough in the eastern Atlantic bringing some very unsettled weather to all before settling down to a slightly quieter zonal flow.

This theme continues but signs of some ridging from the south west/ south east around the 24th – 28th so more settled conditions, certainly in the south with temps a little above average.

After this there is a tendency for the trough to the NW to move east accompanied by slight pressure rises to the west.

Summary

A flow from the westerly quadrant for the whole of the period which will bring periods of very unsettled weather as systems move in from the Atlantic. Quite wintry in the north with some snow and strong winds. The latter could even affect the south at times. This though interspersed with more settled periods particularly in the south. Temps will vary quite a bit around the mean as systems move through and with the interplay of the Pm and Tm air.

Keep in mind this is not taken from the full suite output so some nuances will be missed although broadly speaking it wont be far from the money.

I should have added that the control at the end of the run has strong ridging to the west and a trough to the east.

The gfs run this morning the usual dog's breakfast

Edited December 4, 2015 by knocker

[Mucka]

ECM going for a couple of chilly days.

 

 

I don't see any reason to be disappointed with this mornings output if you want the chance of colder weather and snow later in the Month.

We have made some good strides over the last couple of days even if there is still little sign of a proper blocked cold spell out to final 3rd of month.

[knocker]

The ecm this morning is the usual mixed bag of Pm and Tm, quite warm on some occasions and cool on others, ending with the proverbial N/S split.

Charts weatherbell

Edited December 4, 2015 by knocker

[jvenge]

25 minutes ago, knocker said:

The ecm this morning is the usual mixed bag of Pm and Tm, quite warm on some occasions and cool on others, ending with the proverbial N/S split.

Charts weatherbell

That's interesting at 10 days, for me anyway ;-) Likely not much chance of it happening though.

 

[bluearmy]

Whilst I see little of any concrete nature to get me interested re proper cold pre last week December, the general look of the NH profile on the last two ecm ops are not without quite a lot of promise for later in  week 3. 

[knocker]

There was a message in the woodshed this morning saying possible snow in Cumbernauld for the New Year with ridging to the west and a trough Scandinavia down into central Europe.

[chris55]

GFS FI. Perfect timing for a pattern change ;);) lol

 

[chris55]

ECM also going for a slackening of the pattern in the longer range.

Not much consistency between the two models but we have to start somewhere eh.

 

 

[warrenb]

Look at the ECM, what has happened to the PV, good signs for the turn of the year

[Frosty.]

Fingers crossed the Gfs 00z is right about bringing a generally colder but still very unsettled pattern from later next week onwards with an increasing chance of snow, hopefully the current spell of very mild mush won't last much longer!

[Nouska]

1 hour ago, knocker said:

There was a message in the woodshed this morning saying possible snow in Cumbernauld for the New Year with ridging to the west and a trough Scandinavia down into central Europe.

A good excuse not to visit the outlaws..... 

Meanwhile, European woodsheds look to be largely undisturbed from usage or by infestations from the east. 

[Iceberg]

Very Good 06 GFS full of potential from T144 to T180 thanks to the change of LP direction off the States, the artic high is allowed to migrate further into Greenland, good position of jet and cold comes in..Again very plausible and the models include the ECM have been dropping very heavy hints of a pattern change.

[joggs]

Then gone on the next run lol.GFS leading us up garden path again? 

Until the meto state a change in pattern or Jh charts,count me out.

[Yarmy]

If only...

 

 

Has there ever been a North American synoptic pattern that looked like that in mid-December?

[Weather of Mass Disruption]

5 hours ago, Mucka said:

Ho ho ho

 

I'll take that on the 16th as it would be a very welcome birthday present! 

[Ali1977]

Amazing GFS.

[Tim Bland]

1050 Greenland high anyone? This would be the start of a long cold spell ! ..

[Ali1977]

Let's see if the ensembles show support....Chrismas commuting could get tricky going on from these charts.

[tight isobar]

This morning s suite leaving a lot to ponder mid month onwards. ....

I think its almost nailed foe a mid month pattern change...perhaps in a more notable way than some suspect! !!

Some interesting output.

[Frosty.]

The Gfs 6z turns into a dream run for coldies with reload after reload of wintry weather from the Arctic. I think something significantly wintry is brewing as we head towards mid december onwards, hope we see much more of this on future runs to bring some much needed cheer to coldies, especially those in the south!

[Polar Maritime]

Yes Karl, The GFS has been hinting a change of sorts from the North around the 12/13th for a good while now, And the 6z certainly maintians that theme again this morning. With High Pressure shown pushing up into Greenland. Certainly a colder 2nd half of December coming up with more of a Wintry flavour. .

 

Edited December 4, 2015 by Polar Maritime
charts back to front..

[knocker]

The ecm anomaly this morning tells a familiar tale upstream and the trough in the NE Atlantic so the unsettled theme continues.  The ext ecm has LP over the Pole, HP GOA, flat pattern across N. America with trough eastern Atlantic and eastern Europe so more of the same.

 

[nick sussex]

Hope at last for coldies but not a done deal yet.

Reading through the extended forecast discussion from NCEP, a more amplified flow is expected to develop across the USA. I think the issue remains that chunk of PV left over in Greenland and whether there might be enough WAA ahead of the troughing in the USA to lift heights there.

The GFS 06 hrs run has moved inline with the ECM 00hrs upstream at T240hrs, the trigger for any cold for the UK will be that deepish low moving through the USA, with the right amplitude this could deliver enough WAA into Greenland to downstream develop a north or nw flow.

Fingers crossed that this trend sticks and we see this moving into the more reliable timeframe.

 

 

[gottolovethisweather]

8 minutes ago, Polar Maritime said:

Yes Karl, The GFS has been hinting a change of sorts from the North around the 12/13th for a good while now, And the 6z certainly maintians that theme again this morning. With High Pressure shown pushing up into Greenland. Certainly a colder 2nd half of December coming up with more of a Wintry flavour. .

 

Yes indeed PM, see the following post from the last day of November. In there I made a reference to being cautious yet remaining optimistic. My view was that I'd like to see such Northerly teases in the reliable timeframe which still applies but we are slowly nearing those D5 to D7 timeframes to which I mention. December 12th remains a date to watch in my book but the significance of this date in my mind will only remain should we see consistency in the outputs post the HP ridge event mid-next week. I'm taking early bookings for our future emotional model rollercoaster ride events at a discounted price as of today, anyone interested, priced at 19.47 a ticket. EYES DOWN! 

[BLAST FROM THE PAST]

12 minutes ago, nick sussex said:

Hope at last for coldies but not a done deal yet.

Reading through the extended forecast discussion from NCEP, a more amplified flow is expected to develop across the USA. I think the issue remains that chunk of PV left over in Greenland and whether there might be enough WAA ahead of the troughing in the USA to lift heights there.

The GFS 06 hrs run has moved inline with the ECM 00hrs upstream at T240hrs, the trigger for any cold for the UK will be that deepish low moving through the USA, with the right amplitude this could deliver enough WAA into Greenland to downstream develop a north or nw flow.

Fingers crossed that this trend sticks and we see this moving into the more reliable timeframe.

 

 

I've always had and have hope Nick.....being the archetypal coldie optimist

 

Yes good spot re ECM and 06GFS, that looks like parity there.   

 

BFTP

Edited December 4, 2015 by BLAST FROM THE PAST