Model output discussion - 20th Feb onwards

[Frosty.]

I just had to check whether it was still April fools day when I viewed the Gfs 00z op run in low res which show widespread snow and frosts.....stunning

[knocker]

The GEFS and ecm anomalies at T144 are identical with a trough shooting out from the deep cold trough over N. America and disrupting the HP in the western Atlantic.This develops rapidly into some high amplification in the Atlantic with ridging into Greenland becoming reestablished and a quite intense upper low SW of Ireland. This could well produce some interesting and unsettled weather over the UK, rather depends a little on where the surface low resides. Perhaps some heavy shower activity with some hail and thunder thrown and some longer periods of rain but also some pleasant drier periods. Probably drier in the north and generally temps a little below average.

No significant change in the final five days of the period.

 

 

[Frosty.]

Yesterday I said I'm not dreaming of a cold April but the coldie in me was impressed by those Gfs 00z charts I posted earlier, really stunning synoptics which would bring meltdown to this forum in winter and shows that even after mid April it would still pack a punch...and the Ecm 00z is also going for a colder, showery spell from later next week and a bit of fine tuning towards the end of the run would deliver an Arctic blast with -10 T850's. It shows we could yet have a wintry sting in the tail this month!

[A.J]

2 hours ago, Frosty. said:

I just had to check whether it was still April fools day when I viewed the Gfs 00z op run in low res which show widespread snow and frosts.....stunning

love your posts Karl, but I have to be the party pooper on this occasion...............Those deep FI charts (which have a miniscule chance of verifying at this range,)show generally cold and dry conditions....even if they somehow verify (not impossible of course) .....the same model run using ppn grid values show a different story with relatively dry conditions with some small amounts of wintry ppn over the high ground of the west country, wales, pennines, and north of the border.....apologies for the critique buddy, but IMHO the call for widespread snow is pushing it a bit 

Edited April 2, 2016 by ajpoolshark

[Frosty.]

2 minutes ago, ajpoolshark said:

love your posts Karl, but I have to be the party pooper on this occasion...............Those deep FI charts (which have a miniscule chance of verifying at this range,)show generally cold and dry conditions....even if they somehow verify (not impossible of course) .....the same model run using ppn grid values show a different story with relatively dry conditions with some small amounts of wintry ppn over the high ground of the west country, wales, pennines, and north of the border.....apologies for the critique buddy, but IMHO the call for widespread snow is pushing it a bit 

Cheers AJ I just got a bit carried away, I guess that was bound to happen after one of the warmest winter's ever recorded across England and Wales so that's my excuse. I noticed a few hard-core coldies were around earlier and however unrealistic those charts are it was still nice to see them and I'm sure Dr Judah Cohen would agree.

[A.J]

3 minutes ago, Frosty. said:

Cheers AJ I just got a bit carried away, I guess that was bound to happen after one of the warmest winter's ever recorded across England and Wales so that's my excuse. I noticed a few hard-core coldies were around earlier and however unrealistic those charts are it was still nice to see them and I'm sure Dr Judah Cohen would agree.

no worries buddy, you never know though, one day one of the low res GFS outputs will verify .....I wasn't trying to come across as a bit of a smarta*se or anything, but I know quite a few follow your posts, just wanted to save said people from getting their hopes up too much (not due to following your posts of course, rather falling victim to the GFS FI 'bait and switch' output)

[knocker]

Well the hard-core coldies can return to hibernation (probably until next January).

[Frosty.]

2 minutes ago, ajpoolshark said:

no worries buddy, you never know though, one day one of the low res GFS outputs will verify .....I wasn't trying to come across as a bit of a smarta*se or anything, but I know quite a few follow your posts, just wanted to save said people from getting their hopes up too much (not due to following your posts of course, rather falling victim to the GFS FI 'bait and switch' output)

No worries AJ, I did my best all winter for the cold cause but it was a nightmare and I know you wernt trying to come across as a bit of a smarta*se because I have always respected your input on netweather..cheers again buddy

[damianslaw]

Continue to dip in and out of model watching - for various reasons... Glancing at the models this morning, nothing warm or dry on the horizon anytime soon, indeed after this weekend it looks distinctly unsettled and rather cool, possibly cold as we head further towards the middle of the month. Strong signal for a diving deep trough to dig across the country with a rapid rise of heights over mid atlantic into Greenland - nothing too unusual, but it would bring rather unpleasant conditions and certainly snow to higher ground in the north.

April is our most fickle month - two faced April, the cruellest month they call it, as we see flip flops between early warmth and the last vagaries of winter cold, northerlies often spring up out of nowhere sometimes on the back of southerlies and vice versa, troughs can suddenly become slow moving sluggish affairs enabling innocuous looking height rises to become super features often in the wrong position for warm and sunny weather - there are exceptions though April 2007 and 2011 notably so.. Its the month most hardest to predict.

 

[phil nw.]

GFS 06z run shows what cold lovers were seeking earlier in the year.

the deep cold from the pole finally being released towards us via N.Scandinavia.

Of course now it's too late for anything wintry of note away from northern hills as the cold pool available is now declining and the warmer air to the south means any real cold will soon modify on it's journey towards the UK.

It will create some heavy  and possibly thundery showers though with that upper cold pool in place so some dramatic cloud formations look likely in the unstable atmosphere.

[Frosty.]

15 minutes ago, phil nw. said:

 

Of course now it's too late for anything wintry of note away from northern hills as the cold pool available is now declining and the warmer air to the south means any real cold will soon modify on it's journey towards the UK.

 

Late April 1981 shows its not too late

[knocker]

 

And of course moving on slightly we are in Sidney heaven with a southerly flow.

Edited April 2, 2016 by knocker

[MP-R]

2 hours ago, phil nw. said:

GFS 06z run shows what cold lovers were seeking earlier in the year.

the deep cold from the pole finally being released towards us via N.Scandinavia.

Of course now it's too late for anything wintry of note away from northern hills as the cold pool available is now declining and the warmer air to the south means any real cold will soon modify on it's journey towards the UK.

It will create some heavy  and possibly thundery showers though with that upper cold pool in place so some dramatic cloud formations look likely in the unstable atmosphere.

Unfortunately those were the very charts we saw earlier in the year, that delivered sod all. Air from the north with uppers around -4C to -6C at best, therefore a wintry mix for most, which in April, as you say, will bring very different weather conditions in the form of excellent convection and potent spring showers. A lot less cold air to tap into now than earlier in the year.

[knocker]

59 minutes ago, MP-R said:

Unfortunately those were the very charts we saw earlier in the year, that delivered sod all. Air from the north with uppers around -4C to -6C at best, therefore a wintry mix for most, which in April, as you say, will bring very different weather conditions in the form of excellent convection and potent spring showers. A lot less cold air to tap into now than earlier in the year.

Indeed, particularly when one considers the 500mb and surface temp anomalies over that time frame.

 

[knocker]

The GEFS anomalies still running with the evolution of the trough emanating from the cold trough over N. America phasing with the UK trough whilst building heights into Greenland in the western Atlantic. Ergo an area of low pressure very adjacent to the UK which could herald some nice convective stuff along with some drier sunny intervals. Temps generally around average.

[Milhouse]

The Azores high looks like taking a long holiday away from the UK so it looks like the best route to something warm will be from the Euro high drawing up warm southerlies as low pressure pulls back west into the Atlantic. Ecm 12z shows how this would develop. Before that its looking generally unsettled though very mild at first with temps dropping back to average/slightly below.

 

[Singularity]

Interesting again from ECM. Looks like we'll have both unseasonably cold and unseasonably warm airmasses moving/developing close to our shores as we approach the halfway point this month.

GFS has managed to keep us on the warmer side for a large part of its 12z run, but without enough amplification to produce markedly warm conditions - just a bit above average with a lot of rain about. Being on such a pronounced cold/warm boundary is a recipe for a very soggy month. In these parts it could mean 2016 continues to chase 2014 for the wettest first four months of the year - though it's currently still more than 100 mm short despite being the second wettest in the past two decades. Jan-Feb 2014 was just insane.

[knocker]

Good agreement this evening between NOAA and the ecm in the 5-10 range with strong amplification, ridging into Greenland with upper low just SW of Ireland. So the prognosis is the same as before, unsettled with heavy showers, perhaps thundery activity, with occasional longer spells of rain but some pleasant interludes as well. Temps on the nippy side as a little below average.

 

Not a huge difference in the latter time frame except the EPS has the low rather more to the west thus veering the wind into a more SW flow and bringing the temps to nearer average.

[knocker]

Not a hundred miles away from what the anomalies were indicating last night. Anyone for a Spring break in Spain. Sidney's Spanish cousins are not amused. And this morning's come to that.

Edited April 3, 2016 by knocker

[northwestsnow]

As is becoming the norm in recent years, a winter void of any meaningful Greenland blocking is being followed by some pretty strong blocking highs in April.

Maybe its sods law but im getting a feeling of deja vu here.

April is shaping up to be a poor month for anything warm and settled, the jet is going so far south even the canaries looks iffy certainly for the first half of the month !!

Bitterly disappointing for coldies seeing massive blocking and a southerly jet in April,even the south looks wet at times as the lows to the south do their thing.

[knocker]

And the ecm

[tinybill]

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=2&ech=204

 

just  looked into  fantasy world spain  could see snow there in April!!!

[Nouska]

The oft quoted "flow from Siberia" in Dr Cohen's blogs has finally made it on to the pages of the NWP - albeit,  mixed with wrap around from the Med.

2 hours ago, northwestsnow said:

Bitterly disappointing for coldies seeing massive blocking and a southerly jet in April,even the south looks wet at times as the lows to the south do their thing.

I would imagine it is bitterly disappointing for most people in terms of sensible weather but the convective enthusiasts will have plenty to cheer.

[jamie82]

3 hours ago, northwestsnow said:

As is becoming the norm in recent years, a winter void of any meaningful Greenland blocking is being followed by some pretty strong blocking highs in April.

Maybe its sods law but im getting a feeling of deja vu here.

April is shaping up to be a poor month for anything warm and settled, the jet is going so far south even the canaries looks iffy certainly for the first half of the month !!

Bitterly disappointing for coldies seeing massive blocking and a southerly jet in April,even the south looks wet at times as the lows to the south do their thing.

Indeed, I am currently in Lanzarote and it's very unsettled and cool. 

[Frosty.]

Nice warm end to the Gfs 6z this morning, I am so looking forward to potential Spanish plumes from May until September!