Model Output Discussions 12z 01/09/2016

[Summer Sun]

This evening's ECM ens shows winds shifting around to more of a westerly during the 2nd half of next week with temperatures slowly but surely recovering

[Frosty.]

2 minutes ago, Summer Sun said:

This evening's ECM ens shows winds shifting around to more of a westerly during the 2nd half of next week with temperatures slowly but surely recovering

It's far from a done deal Gavin, still lots of uncertainty beyond the increasingly cold weekend and cold first half of next week with confidence in the forecast currently low beyond next Wed. :- )

[Summer Sun]

2 minutes ago, Frosty. said:

It's far from a done deal Gavin, still lots of uncertainty beyond the increasingly cold weekend and cold first half of next week with confidence in the forecast currently low beyond next Wed. :- )

Indeed this sort of jet stream isn't what we've become used to over recent autumn's

[Frosty.]

4 minutes ago, Summer Sun said:

Indeed this sort of jet stream isn't what we've become used to over recent autumn's

Indeed, more twists and turns are likely in the unreliable timeframe and we have our first arctic shot in the bag

[Mucka]

3 hours ago, knocker said:

Mucka

I'm sure we could discuss the meteorological aspects of this for quite some time but it's really suffice to know what people mean in the context of the thread. So in this context the upper low on Friday is a slider and phases in with the cold air of the main upper trough. By the way have you noticed this evening's GFS is being quite wicked and shifting warmer air eastwards from the middle of next week.

Yup

It is very much swinging back and forth, this mornings output was more favourable for blocking, this evenings more for sweeping westerlies.

I expect there will be plenty more swings next 24/48 hrs.

I have just quoted and replied here before reading all the other posts so this has probably already been posted but JMA at least going for a disrupting/sliding/undercutting low - whichever our preferred flavour of wintry synoptic. 

[lorenzo]

JMA is well respected by UKMO - Ian summed it up by citing the nuances of forecasting for such a small landmass - Japan akin to the UK given ocean proximity.

Some data here

http://ds.data.jma.go.jp/gmd/tcc/tcc/products/model/verif/1mE/Map_discussion/ACOR/vrfmap_acc_z500_nh_52wmean.e.html

Model verification in mind Dr Maue put a tweet up this week showing the slightest incremental increase in skill demonstrated by the new ECM - really is a case now it would seem of massive effort to make the smallest gains.

Hey - every model has it's day during winter and all can 'sniff' something out. That's the fun of looking at them

[feb1991blizzard]

3 minutes ago, lorenzo said:

JMA is well respected by UKMO - Ian summed it up by citing the nuances of forecasting for such a small landmass - Japan akin to the UK given ocean proximity.

Some data here

http://ds.data.jma.go.jp/gmd/tcc/tcc/products/model/verif/1mE/Map_discussion/ACOR/vrfmap_acc_z500_nh_52wmean.e.html

Model verification in mind Dr Maue put a tweet up this week showing the slightest incremental increase in skill demonstrated by the new ECM - really is a case now it would seem of massive effort to make the smallest gains.

Hey - every model has it's day during winter and all can 'sniff' something out. That's the fun of looking at them

I don't rate the JMA or the GEM tbh, the much maligned GFS is still what it is, a consistent NO.3, there was a time, not long after i became a member on here, where i rated the UKMO 12z above the ECM and GFS, they swap around a bit in my eyes but the usual order is correct for me, that's gut feel btw, i don't keep any stats, i only really use the others when its a tie and you need a decider.

[karlos1983]

In summary,  it depends whether it shows what your looking for. The NAVGEM had my respect this morning 

lets see if we can get a pub run special. 

[BLAST FROM THE PAST]

2 hours ago, Summer Sun said:

Indeed this sort of jet stream isn't what we've become used to over recent autumn's

Well although we have been wet and stormy (last couple of winters), the storm tracks have been well more south hence the huge amounts of hits and exceptional floods. Indeed the north south contrasts have been very stark....for me indicative of a very perturbed jet-stream (as it is now but causing different affects on UK

 

BFTP

Edited November 2, 2016 by BLAST FROM THE PAST

[chrisbell-nottheweatherman]

46 minutes ago, Summer Sun said:

Indeed this sort of jet stream isn't what we've become used to over recent autumn's

That's almost the dictionary definition of a meriodional jet.

[Methuselah]

Just now, BLAST FROM THE PAST said:

Well although we have been wet and stormy, the storm tracks have been well more south hence the huge amounts of hits and exceptional floods. Indeed the north south contrasts have been very stark....for me indicative of a very perturbed jet-stream.?

 

BFTP

We haven't had a storm for weeks, Fred?

[feb1991blizzard]

Just now, Ed Stone said:

We haven't had a storm for weeks, Fred?

I think he's on about recent winters.

[Barry12]

I really rate the NASA model personally...

[legritter]

Will current gfs run show increasing high pressure over scandy ,steady as she goes ,but wont be staying up to find out ,going to check up tomorrow after mornings runs but looks interesting ,cheers .

[Ali1977]

Is this another load of WAA about to head in to the block?

Not quite but it stops the lower heights heading SW from Greenland keeping us a dryer set up - will keep us going with the cold nights.

Edited November 2, 2016 by Ali1977

[knocker]

If one takes the progression of the EPS 6-10 anomalies and continue it for the next five days it will jjust about cover the 10-15. In other words it continues to deamplify and we end with HP to the SW, low pressure over Iceland and a westerly upper flow with temps average, perhaps a little above,

 

[Ali1977]

Look at the differences over NE Canada and Greenland - could be good news.

[Frosty.]

1 hour ago, Ed Stone said:

Usually yes but, sometimes, it forecasts loads of snow...And, in such situations, it's the beez neez!

Can't wait to see what the JMA 00z shows

More of this please!

[weirpig]

22 minutes ago, Frosty. said:

Can't wait to see what the JMA 00z shows

More of this please!

 

[weirpig]

Well the gfs is going crazy in fl 

[karlos1983]

Fl northerly seems to be the new trend. That's 2 runs in succession now from gfs. 

 

[Frosty.]

The Gfs 18z still looks great this weekend into early next week with the first of hopefully many arctic incursions, there then follows a flatter, milder blip but this is followed by further polar / arctic maritime as the jet axis sharply tilts nw / se with vigorous lows dive bombing the uk from the northwest.

Edited November 2, 2016 by Frosty.

[feb1991blizzard]

3 minutes ago, karlos1983 said:

Fl northerly seems to be the new trend. That's 2 runs in succession now from gfs. 

 

There is loads to be said about todays modelling and although people wont see it this way, most of it is good news in my opinion, look at the third successive good strat run for starters.

[karlos1983]

5 minutes ago, feb1991blizzard said:

There is loads to be said about todays modelling and although people wont see it this way, most of it is good news in my opinion, look at the third successive good strat run for starters.

Yes i noticed that, although quite a step down from the bullish 06z run. But I seem to remember hearing the 06z has a habit of overplaying strat events?

i think today has been just fine. 

Edited November 2, 2016 by karlos1983

[feb1991blizzard]

Just now, karlos1983 said:

Yes i noticed that, although quite a step down from the bullish 06z run. But I seem to remember hearing the 06z has a habit of overplaying strat events?

Ive never actually heard someone say it but lately yes it has had a habit, but look at the 10mb and 30mb charts now - not bad.

http://www.instantweathermaps.com/GFS-php/showmap-strat.php?run=2014110218&var=HGT&lev=10mb&hour=384