Model Output Discussion - The Start Of Winter

[Nouska]

Interesting four panel from ECM at T162 - heavy precip, T850s sub -5c and the 528 line well south. Courtesy IMO.

 

http://brunnur.vedur.is/kort/ecm0125/2014/12/05/12/ecm0125_nat_4panel1_2014120512_162.png

 

[Mucka]

RE a more northerly flow it is really all about the low being held back and not phasing with the Atlantic trough which GFS had been doing until today.

The deeper the trough the more amplified the upstream pattern was going to be so long as this phasing did not occur.

How that cut off low is modeled in upcoming runs should make for interesting viewing and we also have hints of height rises to our East being possible (JMA)

Fascinating. (Captain)

[Nick L]

Model discussion please.

[SE Blizzards]

RE the CFS, I had noticed that the HLB signal for January had disappeared over the past week (to be replaced with something akin to what we have now). I wonder if this is the reason?

 

 

Hi CC.

 

Ironically, since you said about the disappearing signal of HLB for January i have kept an eye on the CFS, and to be honest HLB for january has come back quite strongly in it's last few updates.

 

Here's the most recent update for January...

 

 

 

 

And just for fun, here's February...

 

 

 

[Cheshire Freeze]

Hi CC.

 

Ironically, since you said about the disappearing signal of HLB for January i have kept an eye on the CFS, and to be honest HLB for january has come back quite strongly in it's last few updates.

 

Here's the most recent update for January...

 

 

 

 

And just for fun, here's February...

 

 

 

It doesn't surprise me. Usually the opposite of what I say happens. Just one of those things

[Jason T]

Evening all, Plenty to talk about in the current output now. Just thought i would post this link reagrding Agreements from different Models. These are all on one page, Some probably have this already but for those that do not..Here you go.

 

http://www.meteociel.fr/cartes_obs/comp_panel.php?mode=1&ech=54&size=1

 

Take Care all.

[Snowman.]

It doesn't surprise me. Usually the opposite of what I say happens. Just one of those things

I've been looking at it for the past few and I never saw anything for January just close calls...

 

Feb however it's been banging on about since November.

Edited December 5, 2014 by SN0WM4N

[Paul]

This isn't due to go live on the site until tomorrow, but since I just finished the main part of it I thought I'd share in here. 

 

We've now got free viewers for the NetWx-SR and NetWx-MR models (were the NMM's) - our in house hi-res models. The SR is a short range (48 hour) 4km model for the UK, with the MR running out to 7 days at 12km resolution.

 

SR:

http://www.netweather.tv/index.cgi?action=netwx-sr;sess=

 

MR

http://www.netweather.tv/index.cgi?action=netwx-mr;sess=

 

I hope you like them

 

Ps - For Netweather Extra (and Extra Lite) subscribers these pages will automatically take you to the subscriber versions of these charts rather than the free one if you're logged in.

[knocker]

Tonight's anomalies.

 

NOAA 6-10 has trough just north of the UK orientated slightly SE; HP amplification North America and low Pacific. Azores HP orientated south of east meaning the UK temporarily under the influence of the low pressure. The 8-14 has the  trough more east west allowing the HP to push further north into the UK.

 

The GEFS and ECM have pretty similar scenarios with the HP to the east over N. Europe.

 

The extended versions of the ECM and GEFs have less influence from the trough and more from the Azores HP.

 

Surface analysis is after briefly flirting with the low pressure to the north and NE the HP becomes more dominate in the later stages. Temps  below average and briefly quite cold then becoming average.

 

Verdict. No major changes in the overall pattern.

 

Charts courtesy weatherbell.

Edited December 5, 2014 by knocker

[Frosty.]

Although I've not been well today I think my negative comments earlier and a dash of reverse psychology has done the trick. We could be on course for our first real taste of winter later next week with a potent Northerly blast bringing snow showers and sharp frosts..fingers crossed guys. :- )

[blizzard81]

Well, fasten your seat belts everybody, it's going to get much colder during the middle third of Dec.

The ECM and GFS agree on this and I have noticed an almost firm transition day of the 10th Dec that

has kept cropping up over the last few days on and off. Today though has almost cemented this date as the

day to watch the transition unfold. This will herald a much colder middle third of Dec defined by trough digging

south east into Europe followed by north easterly drift backing into easterly. Not frigid by any means but so much

better than last winter. Whether this cold can hang on for Xmas week is another question but fingers crossed.

Just wanted to bring this post I made on Monday night back to the fore. Everything still firmly on track and no revisions necessary. In fact I believe tonight's ECM op was in this ball park. Edited December 5, 2014 by blizzard81

[Gibby]

No comments on tonight's 10 Day ECM Mean. Doesn't look that exciting to me around the UK.

http://www.wetterzentrale.de/pics/Reem2401.gif

Edited December 5, 2014 by Polar Maritime
If you aren't going to comment, Don't post the chart.

[nick sussex]

No comments on tonight's 10 Day ECM Mean. Doesn't look that exciting to me around the UK.

http://www.wetterzentrale.de/pics/Reem2401.gif

Perhaps these comments from NCEP forecast for New York in their latest update might shed some light on why the ensembles might be painting a false picture:

 

ATTENTION THEN TURNS TO THE STORM EXPECTED TO DEVELOP OFF THE EAST

COAST BEGINNING MON NIGHT. SIDING MORE AND MORE WITH A MORE

AMPLIFIED SOLUTION PER LAST TWO RUNS OF THE ECMWF FOR THIS EVENT...

AS AN AMPLIFYING NRN STREAM PHASES WITH A PAIR OF DISTINCT

SHORTWAVES MIGRATING FROM THE NRN ROCKIES AND DESERT SW IN SPLIT

FLOW ALOFT...AND A WEAK SFC WAVE ALONG A STALLED FRONTAL ZONE OFF

THE SE COAST. TREND HAS BEEN FOR THIS LOW TO DEVELOP CLOSER TO THE

COAST LATE MON NIGHT TUE MORNING...THEN QUICKLY INTENSIFY OFF THE

MID ATLANTIC COAST. LATEST RUNS OF THE ECMWF AND THE 00Z ECMWF

ENSMEAN DIVERGE FROM THAT POINT ON...WITH THE OPERATIONAL RUNS

TRENDING TOWARD A MORE INTENSE LOW WITH WARM SECLUSION REACHING PEAK

INTENSITY TUE NIGHT NEAR THE NY BIGHT...AND THE 00Z ENSMEAN SHOWING

A MORE OFFSHORE LOW TRACK. GIVEN THE INCREASING POTENTIAL FOR

GREATER PHASING OF THE VARIOUS STREAMS ALOFT...THINK THE OPERATIONAL

TREND IS MORE ON TRACK.

 

The more coastal track impacts on the ridge ahead of it so if some of those  GEFS and ECM ensembles are taking the low off shore downstream this would lead to more flatness to those solutions.

 

[shaky]

No comments on tonight's 10 Day ECM Mean. Doesn't look that exciting to me around the UK.

http://www.wetterzentrale.de/pics/Reem2401.gif

that is one rubbish mean man!! I honestly thought I'd see a bit more of a dig of low pressure into europe and slightly higher heights across greenland! ! Azores high is in a worrying position aswell!!

[gottolovethisweather]

Just wanted to bring this post I made on Monday night back to the fore. Everything still firmly on track and no revisions necessary. In fact I believe tonight's ECM op was in this ball park.

 

FWIW I think you might be onto something too regarding the trough digging SE as I've been watching the NH pattern closely on the ECM 12z over a number of days recently.   The UKMO outputs are tending to head in a similar direction too.

 

Once we get past next Wednesday's deep depression, things will be much clearer, but the signs are there for a continuance of the cool to cold picture PM flows for now. Whether deep cold start of a more prolonged nature starts showing up in reliable timeframes across NWP outputs by next Wednesday, who knows, but there is plenty to keep a watch on in the meanwhile as to how things are developing NH wise.

Edited December 5, 2014 by gottolovethisweather

[BLAST FROM THE PAST]

Early stages and not much difference but I think we are seeing a tad more amplification in early stages here on the 18z.  With that I've probably caused it to flatline......

 

BFTP

[BLAST FROM THE PAST]

Just wanted to bring this post I made on Monday night back to the fore. Everything still firmly on track and no revisions necessary. In fact I believe tonight's ECM op was in this ball park.

I'm on your side B81...and some 

 

BFTP

[gottolovethisweather]

that is one rubbish mean man!! I honestly thought I'd see a bit more of a dig of low pressure into europe and slightly higher heights across greenland! ! Azores high is in a worrying position aswell!!

 

The Azores High is not of concern right now and won't be generally in the UK weather picture for at least another week, in the meanwhile the nearby continent gets ever colder with snow nearing central parts of Europe. The continuance of PM flows is the main weather signal within the reliable timeframe and ramifications from the pacific region (Typhoon thingmebob) and its knock-on effects on the US, along with any Arctic blocking signals would override any influence the Azores High has on the UK I would imagine. Whether by Mid-December we see the current coolness relent is up for debate, but to my mind, mid-December onwards we're more likely to see a drier picture develop as Xmas approaches and I can almost hear the weatherman saying at least "it won't be mild". Admittedly, the last bit is beyond model projections and is a kind of fantasy prediction from my "gut", however, these gut instincts can often come true too.

Edited December 5, 2014 by gottolovethisweather

[Recretos]

Hi CC.

 

Ironically, since you said about the disappearing signal of HLB for January i have kept an eye on the CFS, and to be honest HLB for january has come back quite strongly in it's last few updates.

 

 

I was playing around with its files earlier, and its actually pushing for an SSW in Jan. So what you are seeing is actually SSW response.

[Cloud 10]

No comments on tonight's 10 Day ECM Mean. Doesn't look that exciting to me around the UK.

http://www.wetterzentrale.de/pics/Reem2401.gif

 

 

Looks to be a similar theme to recent runs with a cool/cold NW flow with the odd milder day thrown in,so pretty much a "steady away"start to winter.

 

[BLAST FROM THE PAST]

I think this is going to lead to a more extreme northerly blast than 12z.  Slightly slower but more pronounced lower heights  in Med. 

 

 

Look around Hudson Bay too, trough further south so block in Greenland should hold better...

 

 

 

 

but it collapses?  Mind you seeing how the models perform, what is the concern that far out?

 

 

BFTP

Edited December 5, 2014 by BLAST FROM THE PAST

[Captain Shortwave]

The cut off low over Eastern Canada will raise the stakes on model uncertainty as the models naturally will tend to throw various solutions on the journey of this low and hence the pattern downstream

The pub run shows this pretty much banished from the polar front jet. No sign of it re-engaging any-time soon so expect a different solution beyond week 1

[Cheshire Freeze]

If anyone wants to know how the UKMO would have looked at 168 hrs, the 18z would pretty much be it I think. They're pretty similar at 144.

[fergieweather]

No comments on tonight's 10 Day ECM Mean. Doesn't look that exciting to me around the UK.http://www.wetterzentrale.de/pics/Reem2401.gif

...albeit the 12z clusters into that timeframe *could* prove to be.

[bluearmy]

...albeit the 12z clusters into that timeframe *could* prove to be.

Ooh Ian - you tease.

the extended naefs and ECM anomolys aren't inspiring for deep cold but do provide a wide enough envelope to allow interest neater the time. both suites end with high anomolys joining to our north though still weakish. The euro high anomolys showing yesterday are less obvious today as week 2 progresses.

The ECM day 10 spreads have a cluster Iceland/Greenland. I assumed was an area of low heights. Perhaps it wasn't???

Edited December 5, 2014 by bluearmy