Model output discussion 8th Feb - Cold for now, but then what?

[Frosty.]

Really exciting Gfs 12z tomorrow with a snowfest across parts of northern England and Scotland with blizzard conditions and up to 12 inches in places, drifting in the strong winds and that's the other feature, Gale to severe Gale force winds for a time. I would love to be in the middle of that snowy sweet spot! 

[mb018538]

Pretty disappointing 12z....gfs doesn't develop anything really. Ukmo looks to be staying unsettled for the foreseeable. All eyes on ecm tonight.

[knocker]

29 minutes ago, karyo said:

This is a dog's dinner because...?

There is quite a bit of complicated stuff going on ending with complex low pressure systems as in the chart but I accept it's a pretty pathetic way of describing the run so in fact it was better left unsaid.

[Frosty.]

I can't see very much mild weather on the Ecm 12z run, for the most part it looks rather cold with 526 / 528 dam across the uk next week. It's a generally unsettled run too..not spring like at all..a chilly start to march. :- )

Height rises to the NE with scandi high forming it looks increasingly blocked later with the Atlantic held at bay.

Edited February 22, 2017 by Frosty.

[I remember Atlantic 252]

10 minutes ago, Frosty. said:

I can't see very much mild weather on the Ecm 12z run, for the most part it looks rather cold with 528 dam across the uk next week. It's a generally unsettled run too..not spring like at all..a chilly start to march. :- )

can only agree Frosty, it's a vile ECM run (south) just hope it can be as dry as possible, unlikely but never know, miserable weather due after Monday 27th

3rd and 4th down, my favourites on your post Frosty!

Edited February 22, 2017 by I remember Atlantic 252

[Frosty.]

9 minutes ago, I remember Atlantic 252 said:

3rd and 4th down, my favourites on your post Frosty

Yes, briefly milder through the weekend then chilly.

[nick sussex]

Interesting ECM run but the sort of output that leaves you thinking shame it didn't appear a few weeks back.

As you head into March you really need to tap into deeper cold than whats on offer on the ECM. I think for those looking for a last proper gasp of winter we're going to have to see a lobe of the PV drop south which could happen if the pattern retrogressed.

A shortwave complicates matters on the ECM which stopped better ridging nw into Greenland, overall it looks like a coldish start to March but nothing dramatic at this stage.

If the ECM was on the right lines in terms of pattern which of course at this range is a big if, then you'd need to see the pattern retrogress so energy from the upstream troughing disrupting se a ridge building nw in towards Greenland and a chunk of that PV to the ne being pulled sw to help develop much deeper cold to tap into, the trouble some shortwave energy circled red develops earlier and then hangs around.

 

Edited February 22, 2017 by nick sussex

[snowray]

I don't think that it would have made much of a difference if the ECM run had verified in January or early in February, first week of March can produce the goods still without any problems but as usual when we do pick up an easterly or south easterly for that matter, the air to our east is not terribly cold so its the same old close but no cigar.

Something that was showing up a few days ago was the Iceland High, this is what we want ideally with HP extending either west towards GL or east towards Scandi. I bet we do end up with the block in just the right place when its too late, like in late spring or early summer.

[Frosty.]

There are some encouraging longer term signs for cold weather in March from the GEFS 12z..I'm not about to give up!

[Singularity]

With an MJO signal in the Indian Ocean and a stratospheric vortex persistently displaced toward Asia it seems the ingredients for blocking to our NE are there, but the road that the model runs which follow this script are keen to take on the way there leaves not a lot of cold air to be brought our way, resulting in a nuisance chill and little more.

Then we have the sporadic signal for the Atlantic jet to remain strong and keep things mobile for us instead. Possibly the tropospheric polar vortex just doing its own thing rather than aligning with the stratospheric one. I wonder if we might see a halfway house of sorts which sees strong westerlies over a mid-latitude block. Sounds all too familiar doesn't it?

Not hard to figure out why I've been silent for quite a while; ever since the massive modelling fail with respect to mid-Feb there's been a distinct lack of particularly appealing charts to discuss (or at least, within the 10 day range). Tomorrow was briefly an exception but it has since gone too far with the wind and not far enough with the cold air component.

Best case scenario - but not a particularly likely one - that I can see on the cards for pleasant weather is ending up with a mid-lat block but either positioned far south enough that we avoid a nagging easterly or (best of all but also the least likely) aligned in conjunction with a low over Europe in such a way as to send relatively warm air in our direction from the eastern Med.

For cold weather sufficient for widespread lying snow we'd need to see a proper annihilation of the stratospheric vortex and then get very lucky with the orientation of the major building blocks. Not sure I'd want to play that game after such a diabolical winter season in terms of defying our attempts to anticipate it's behaviour (worst I've known since I started paying proper attention a decade ago). 

Okay, time I ditched the morose hat and moved on. Here's to an entertaining spring season 2017 

[Eugene]

1 hour ago, Frosty. said:

I can't see very much mild weather on the Ecm 12z run, for the most part it looks rather cold with 526 / 528 dam across the uk next week. It's a generally unsettled run too..not spring like at all..a chilly start to march. :- )

Height rises to the NE with scandi high forming it looks increasingly blocked later with the Atlantic held at bay.

Yes frosty ECM 12Z is a very encouraging run, we've had a real lack of cold active weather the past few months, tomorrow and next week could deliver some exciting weather esp for northerners, i want to see the jetstream edge further south on future runs and a growing scandy high maybe giving some battleground events.

[knocker]

I'm beginning to get that deja vu feeling again looking at this evening's anomalies. Still pretty good agreement and no significant diversion from the recent indicated evolution.

In the 5-10 range the GOA ridge is now the Aleutian ridge and an intense N. Canadian vortex and associated troughs south over N. America and the negatively tilted one into mid Atlantic. Worth mentioning the positive anomalies north and east of Iceland. Thus the whole of the N. Atlantic is in negative anomaly mode and with the energy emitted upstream rushing east on the upper flow which portends unsettled weather for the UK with periods of wind and rain as systems pass through, Temps obviously varying but generally around average.

There are no massive changes during the 10-15 period. Upstream the ridge continues to retrogress and the vortex becomes a little more diffuse  but the negatively trough into the Atlantic is still the main feature with the positive anomalies and some ridging NW into Iceland playing a slightly more influential role. Thia tends to back the upper flow WSW so a more N/S split vis the unsettled weather may be inclined. temps perhaps a little above average, As ever the details to be sorted by the det runs

Apparently Sidney's in-laws are considering popping down for an early Spring break.

Edited February 22, 2017 by knocker

[Frosty.]

In another winter where there has hardly been any snow its nice to post some Gfs 18z snowy charts. Tomorrow parts of the north look like having significant accumulations, the best snow of this winter so far..enjoy it if you are lucky enough to be in the snow zone!

Edited February 22, 2017 by Frosty.

[Frosty.]

Most of next week looks rather chilly on the Gfs 18z, especially further north but later in the week it turns much milder from the southwest and that is just a little taste of what's to come later in low res with a very pleasant spell of early spring warmth with a generally southerly airflow.

Edited February 22, 2017 by Frosty.

[cheshire snow]

This Morning GFS0z has us in a Northerly flow by T138 With quite a bit of wintry PPN across the UK

C.S

[knocker]

One point of interest this morning vis the GEFS anomalies is the evolution of stronger positive anomalies over Iceland to a cut off high pressure cell as a result of the temporary amplification next week leaving the trough to dominate the Atlantic. This is reflected in this morning's det. run

Once Doris is out of the way fronts associated with depressions tracking east from Iceland bring further rain and strong winds on Saturday. A brief respite before the next depression arrives north of Scotland 970mb by Sunday 18z bringing more fronts and rain to quickly traverse the country. Systems moving rapidly in a strong jet.

This brings us neatly on to Tuesday as the upper trough slides SE over the UK as the Azores ridges north in mid Atlantic. Thus we have a large surface low pressure area over the UK and points east which brings a complete mixture of weather (including a brief northerly as the main depression runs quickly south east)  and even a couple of shallow wave depressions pop along from the NW before the next deep (filling) depression arrives west of Ireland by Saturday. In a nutshell very unsettled with temps quite variable but generally around average.

[mb018538]

I'd go along with that knocker. The beeb in their last 2 nightly forecasts have hinted at things settling down at the end of next week....doesn't look that promising to me at all. That trough out west looks way too dominant.

[Ali1977]

The GFS control is a beauty in the long term, Winter would return. A few decent GEFS in FI but a big spread and most are milder.

[mb018538]

6 minutes ago, Ali1977 said:

The GFS control is a beauty in the long term, Winter would return. A few decent GEFS in FI but a big spread and most are milder.

Sadly a bit of a cold outlier! Lots of ensemble noise after the 1st March, so no clear pattern emerging as of yet. That said, there are about 6/20 members going cold, so it's not without any support. Roughly half of the remaining 14 members keep it mild, with the other half around average. So in a nutshell, we haven't a clue!

[Frosty.]

Next week looks like it would be feeling wintry according to the Gfs 00z with a Northerly flow, night frosts and some snow around too!

Edited February 23, 2017 by Frosty.

[knocker]

Although obviously varying in detail the general theme of unsettled with temps around average is echoed by the ecm.

[Frosty.]

The Ecm 00z looks rather cold too for the most part..chilly and unsettled with snow on hills and occasionally sleet and wet snow to lower levels, especially in the north with some night frosts, a little milder this weekend and towards the end of next week but generally feeling like winter.

Edited February 23, 2017 by Frosty.

[Seasonality]

^^^^^^

I don't know @Frosty. 00z ECM looks just chilly and mucky to me. Neither fish nor fowl. I do love your boundless optimism though, I wish there was more of it in the world.

[Frosty.]

7 minutes ago, Seasonality said:

^^^^^^

I don't know @Frosty. 00z ECM looks just chilly and mucky to me. Neither fish nor fowl. I do love your boundless optimism though, I wish there was more of it in the world.

Thanks but I'm just calling it as I see it, the Gfs / Ecm 00z look generally unsettled and on the chilly side for most of next week with a risk of some snow, especially on hills..could be worse

Edited February 23, 2017 by Frosty.

[knocker]

The ext EPS has the quite intense vortex over N. Canada becoming more diffuse stretching from the Pole around to NE Canada with the negatively tilted trough still running south east into the Atlantic. With some positive anomalies and some ridging NW around Iceland the upper flow remains in the W//WSW quadrant portending a continuation of unsettled conditions with temps around average.