Model Output Discussions 12z 01/09/2016

[legritter]

31 minutes ago, Newberryone said:

Please don't disregard this mods as I feel it's not off topic and overall considerably relevant to the present discussion re medium term cold prospects...Just been listening to this mornings 7:55 weather update from Ireland's met service and what's being forecast from midweek onwards doesn't seem to concur with what we're seeing here on the likes of both the  Ecm and Gfs 00z  

Wednesday will be a mainly dry day with sunny spells followed by a cold, clear night with minimum temperatures coming closer to freezing with light to moderate northwesterly winds. The winds will begin to back to the southwest later. 

The further outlook to towards the end of next week is for southwesterly winds and temperatures around normal for the time of year. There's a signal for a spell of rain for Friday but otherwise a good deal of dry weather.

Thanks for posting Newberryone ,you are posting as you see it and as the professionals are seeing it .If further outlook charts come off its after this that we might All see colder weather i feel ,A Realy dross overcast drizzly day in my kneck of the woods  bring on winter proper ,cheers.

[Ravelin]

I'm sat here with my jaw on the floor this morning . I just can't believe that the models are churning out charts like the following one from the 0Z GFS in November. I know it's in FI but there is just no sign of any organised tropospheric PV, to the extent that there is virtually no low pressure at all in the northern, western hemisphere. 

Edited October 29, 2016 by Polar Maritime
Ridden quote box.

[karlos1983]

1 hour ago, Frosty. said:

I'm liking where this Ecm run is heading..

I'm liking it even more now!

 

Yet again WAA flying north to Greenland. Nice output this morning. Cool down now looks almost nailed on to me, just a question of how cold can we get. 

 

[BLAST FROM THE PAST]

1 hour ago, Newberryone said:

Please don't disregard this mods as I feel it's not off topic and overall considerably relevant to the present discussion re medium term cold prospects...Just been listening to this mornings 7:55 weather update from Ireland's met service and what's being forecast from midweek onwards doesn't seem to concur with what we're seeing here on the likes of both the  Ecm and Gfs 00z  

Wednesday will be a mainly dry day with sunny spells followed by a cold, clear night with minimum temperatures coming closer to freezing with light to moderate northwesterly winds. The winds will begin to back to the southwest later. 

The further outlook to towards the end of next week is for southwesterly winds and temperatures around normal for the time of year. There's a signal for a spell of rain for Friday but otherwise a good deal of dry weather.

This deserves an answer. Look at following chart for Thurs. W to SW winds would be experienced by NI and Scotland.....albeit temporary and average temps.

BFTP

 

[BLAST FROM THE PAST]

Gonna change my Nov CET guess.....downwards!  Monster GFS run for Scandinavia and continued lovely rock solid cold pooling 

 

 

BFTP

[Frosty.]

It's nailed on to become fresher from the north by next midweek and cold, windy & showery across Scotland with the showers becoming wintry on high ground by tues / wed and slight frosts becoming more widespread for a time. The question is whether we will then see a second, stronger surge of cold from the NE or something milder as the Gem 00z shows..but coldies are in a better place than we were 12 months ago for sure!

Edited October 29, 2016 by Frosty.

[Ali1977]

14 minutes ago, Frosty. said:

It's nailed on to become fresher from the north by next midweek and cold, windy & showery across Scotland with the showers becoming wintry on high ground by tues / wed and slight frosts becoming more widespread for a time. The question is whether we will then see a second, stronger surge of cold from the NE or something milder as the Gem 00z shows..but coldies are in a better place than we were 12 months ago for sure!

If the next GFS is similar the the last 2 and latest ECM I imagine we'all see the GEM come on board next run - if it doesn't then it's square 1 again beyond bonfire night. The next seasonal models out next week will be eagerly anticipated by many on here I'm sure.

 

Edited October 29, 2016 by Ali1977

[Frosty.]

Just now, Ali1977 said:

If the next GFS is similar the the last 2 and latest ECM I imagine we'all see the GEM cone on board next run - if it doesn't then it's square 1 again beyond bonfire night. The next seasonal models out next week will be eagerly anticipated by many on here I'm sure.

 

All I know is the models are a lot more interesting than last autumn at this stage..for the majority.

I hope we see something like the Ecm 00z, fingers crossed!

[blizzard81]

The good news is the ECM control run follows the op run with the very cold theme and scrapes to about 1 degree top temp for debilt by day 14. We just need those ensembles to fall in line now over the next couple of runs.

[Ali1977]

The control looks like a very cold run. (Blue dotted line)

Edited October 29, 2016 by Ali1977

[blizzard81]

25 minutes ago, Frosty. said:

All I know is the models are a lot more interesting than last autumn at this stage..for the majority.

I hope we see something like the Ecm 00z, fingers crossed!

Absolutely, it is making for very exciting model watching and it is still only October. Brilliant stuff!

[blizzard81]

I wouldn't be surprised to see the GFS 06z op throw up a milder run only for the 12z to revert back to cold again.

[nick sussex]

Some interesting outputs this morning but too far out to have much confidence in. Looking at the ECM ensemble spreads there looks like a strong signal for pressure to rise in the Arctic regions, the biggest spread is through the UK this will be in relation to how far south high pressure extends from the north. This is likely to go one of two ways, either low pressure stuck over the UK with the coldest air held at bay to the north of the UK or a scenario where low pressure gets sufficiently south to allow that cold air into the UK.

An earlier pointer to how things might turn out is around the T144 to T168 hrs mark, clearance between low pressure near the UK and low pressure near Newfoundland with stronger ridge between those two is a plus if you're looking for the colder solution, a more amplified pattern in the ne USA around that timeframe will help. 

A bad sign is if we see a train of shortwave energy connecting both lows, this will mean high pressure to the north needs to work harder to force the pattern south.

In a nutshell then cold air will be in evidence to the north but it's whether it can get far enough south.

Edited October 29, 2016 by nick sussex

[phil nw.]

Yes modeling continues to show the warm air heading into the Greenland/Canada side of the vortex pushing the core of cold towards Siberia.

A look at the 850's for day 6 on the ECM mean show the gradual extent of the Russian cold heading this way

with the GFS 00z ens graph for C.England showing the step down in the 850hPa temperatures as we go into November -a change to a more Polar air mass

although the Op run was on the cold side of the suite overall the mean trend for a colder spell is very much there.Temperatures down to around average but again low rainfall totals showing that the general dryness of the Autumn continues.

Quite a different season this year with the vortex formation still being held back and that growing continental cold easing ever closer whilst the weakness in the Atlantic jet remains.

 

 

Edited October 29, 2016 by phil nw.

[Iceaxecrampon]

Typical Lancashire murk today - here's one from FI at +348 to liven things up.

 

 

[bluearmy]

Extended ens output continues to head where expected.

Upstream we see a developing east Alaskan upper ridge and east n American trough. that does beef up the jet off the eastern seaboard by the end of week 2 as would be expected. eps are not convincing with a mid Atlantic ridge at that timescale to keep us on the cold side of that strengthened jet so we could see several different  scenarios play out for mid Nov. The GEFS do have a solid mid Atlantic upper ridge towards Greenland at that time so I expect any re invigoration of the PFJ to be displaced well south on an extrapolation of that model mid month. 

Very interesting times and getting to the point where we would be looking for the op ECM to throw a spanner in the works re the general evolution post day 7 as advertised on the ens - runs like the 00z doing the opposite! 

[nick sussex]

In terms of the GFS 06 hrs run so far similar to the earlier run. Crucial timeframe coming up now around T144 to T168 hrs.

Edited October 29, 2016 by ajpoolshark
snipped o/t content

[Frosty.]

Ecm 00z ens mean is heading in the right direction

[shaky]

3 hours ago, Steve Murr said:

Morning -

look at the ECM 192 - western Greenland Hint Hint !!

Very november 2010ish!remarkable similarities!!gfs ukmo and ecm look similar at 144 hours!!

[shaky]

9 minutes ago, nick sussex said:

Thanks, many in the political section will be glad that winters approaching and won't have to put up with as many of my rants! Lol  In terms of the GFS 06 hrs run so far similar to the earlier run. Crucial timeframe coming up now around T144 to T168 hrs.

Looking very good nick on this run around the time frame youve mentioned!!maybe even better than the 00z run with a bit more ridging in the atlantic!!

[stewfox]

34 minutes ago, Iceaxecrampon said:

Typical Lancashire murk today - here's one from FI at +348 to liven things up.

Not back to T348 this year again, that's all we have had in recent years 

We want T48 charts and lots of SM sausages and record breaking negative AO October followed by  lots of Polar Vortex wobbles but in the right place. Promising start.

Edited October 29, 2016 by stewfox

[nick sussex]

4 minutes ago, shaky said:

Looking very good nick on this run around the time frame youve mentioned!!maybe even better than the 00z run with a bit more ridging in the atlantic!!

Bizarre good consistency between two GFS runs! Lol I think we'll need two bites of the cherry here to get the coldest air south, so that shortwave energy you see near southern Greenland at T192 hrs needs to cut se and reinforce the troughing over mainland Europe.

Edited October 29, 2016 by nick sussex

[ALL ABOARD]

17 minutes ago, nick sussex said:

Bizarre good consistency between two GFS runs! Lol I think we'll need two bites of the cherry here to get the coldest air south, so that shortwave energy you see near southern Greenland at T192 hrs needs to cut se and reinforce the troughing over mainland Europe.

No luck this time with the low but even then we end up with this ...






Are we finally entering a period where even when it goes wrong it still ends up right???

[Kieran]

The whole of the country is going to feel cold if the 6z GFS is to be believed

Edited October 29, 2016 by Kieran

[fergieweather]

I subscribe to Bluearmy's cautionary note. Whilst 00z EC EPS agreement is fairly good on a cyclonic NW'ly regime into the 7-10d period, spread has increased (cf 24hrs ago) onwards into d11-15, including the proportion of members exhibiting a leaning towards an increased westerly component. However, it's still a shifting signal, with only a low level of agreement. So, as before, forecast confidence remains effectively low beyond next weekend, albeit continuation of an amplified pattern remains favoured through the 1st half of Nov.