Model Output Discussion - Into Autumn 2020.

[swfc]

Good looking gfs 12z with high level Atlantic riding and cool-cold northerly, be it fi

[mb018538]

Hi, it’s GEM here. I’d like to show you all what a stonkin’ -ve NAO is! 

[Iceaxecrampon]

I wasn't going to look until things (maybe) got going later in the month but Lordy the GFS 12 has a somewhat  chilly chart for October.

[Kirkcaldy Weather]

Theme does seem to be appearing now of the snow and colder air spreading further and further west out of Siberia over the next ten days + , also @Steve Murr ‘s Greenland high going strong on the GEM again 

[Tim Bland]

Still a bIt too early in the season to be talking about the S word but there’s a possibility at the end of the month, especially on higher ground...

[northwestsnow]

GFS brings an early taste of Winter for parts of Scotland in particular.

Not to be totally discounted with Exeters musings suggestive of snow to high ground.

 

[I remember Atlantic 252]

3 minutes ago, northwestsnow said:

GFS brings an early taste of Winter for parts of Scotland in particular.

Not to be totally discounted with Exeters musings suggestive of snow to high ground.

 

low ground too on this not just north either,  but for fun anyway 297 is FI

Edited October 11, 2020 by I remember Atlantic 252

[Iceaxecrampon]

30 minutes ago, northwestsnow said:

GFS brings an early taste of Winter for parts of Scotland in particular.

Not to be totally discounted with Exeters musings suggestive of snow to high ground.

 

 

Exeter = Snow?

[Zak M]

12z GFS shows some snow falling for Norfolk and East Anglia in FI.

Edited October 11, 2020 by Zak M

[Eagle Eye]

No chance for me great i'll just sit and wait for the sme to happen nexy year and the year after that and so on

[I remember Atlantic 252]

so uncertain in FI, EC could create Indian summer if this was placed a bit more north west

[Zak M]

3 minutes ago, I remember Atlantic 252 said:

so uncertain in FI, EC could create Indian summer if this was placed a bit more north west

Oh wow, I love that chart! Perhaps one last chance for a thundery breakdown in the south from this if it comes off?

Edited October 11, 2020 by Zak M

[I remember Atlantic 252]

Aye, I'm not done with summer yet, this is too far East for decent summer 20 degree temps, but at 240, could turn out nothing like this

 

[Mucka]

2 hours ago, Tim Bland said:

Still a bIt too early in the season to be talking about the S word but there’s a possibility at the end of the month, especially on higher ground...

It is so "early in the season" it isn't even "the season" yet!

Eager Beavers here on NetWeather"

ECM would be a sickener in January.

[damianslaw]

Longer term model runs suggesting substantive northern blocking certainly raising the eyebrow at present, backed up by Ensembles. We may well see such heights toned down in future runs, or conversely hold sway, but interesting to note at a stage in the year when typically we see the jet charging into gear and wind and rain is usually the order for the day - but not always.. in the last 12 years late October has brought a mixed variety of conditions, in some years cold northerly plunges such as 2008, 2010, 2012, and 2019. In other years the very mild tropical maritime airstream 2011, 2013, 2014, 2015. Snow can certainly be a low level feature if you have enough cold air, as happened in 2008, 2010 and 2012.

[mb018538]

1 hour ago, I remember Atlantic 252 said:

so uncertain in FI, EC could create Indian summer if this was placed a bit more north west

Too windy for Indian summer weather really....need it a bit calmer and more settled. It’s not actually that warm on that chart - 17c on raw data. 

[Thundery wintry showers]

You might be surprised (I certainly was when I first started getting involved with these weather forums) by how windy southerlies can produce clear sunny weather and unusually high temperatures even in late October.  There was a very good example on 27 October 2005:

and this one from my childhood on 8 October 1995:

So I agree with the "Indian summer" post, although such warm plumes in October tend to be just 36-48 hour events at the most.

[mb018538]

Morning one and all,

A quick update from me about where we are in the short and mid term.

Frontal rain pushing through today, which won't be anything too serious. A quick soaking for a few hours before this clears through. Rain and showers could linger into Wednesday in a few places (eastern areas especially) as low pressure slowly clears and a feed off the North Sea sets in.

From midweek onwards - drier across the UK as a weak ridge of high pressure moves in. A few spots of rain about, but essentially it's a dry picture right out until the end of next weekend. A chance to dry off! Ensemble below shows this dry period:



Beyond this, and ECM and GEM are similar in showing a large low spinning up to the SW of the UK, which would draw up some very mild air, and temperatures probably in the mid to upper teens:




The mega -ve NAO/AO pattern that is setting up also likely to snap back into positive territory towards the end of the month:



This resulting pattern will keep the PV weak for the next couple of weeks though:



In summary - briefly unsettled for a couple of days. Quiet spell from midweek until the end of next weekend, before it likely turns unsettled and milder again.

[Anthony Burden]

The 9 to 10 day breakdown of the high pressure from a vigorous low off the southwest is very much

up in the air.ECM keen on milder southerly winds to most but met office not so keen.

[summer blizzard]

GFS prefers to move the low north east towards the UK along with its tropical moisture source (GEM agrees). 

I would still bet on the Euro but it does highlight the potential for some horrific rain. 

[Cheshire Freeze]

Just a quick one-

Just spotted this in GFS FI...negatively tilted Atlantic troughing. This is a VERY good sign to look out for as we approach November as it's a solid sign that the general pattern is predisposed to blocking at a higher latitude going forward...

[MildCarlilse]

21 hours ago, Mucka said:

It is so "early in the season" it isn't even "the season" yet!

Eager Beavers here on NetWeather"

ECM would be a sickener in January.

There has already been mountain snow in Scotland.

[tinybill]

33 minutes ago, MildCarlilse said:

There has already been mountain snow in Scotland.

their will lbe  people  comeing  out of  hibernation  soon!!!

[feb1991blizzard]

46 minutes ago, CreweCold said:

Just a quick one-

Just spotted this in GFS FI...negatively tilted Atlantic troughing. This is a VERY good sign to look out for as we approach November as it's a solid sign that the general pattern is predisposed to blocking at a higher latitude going forward...

 

The OPI looks like it would have recorded a strongly negative value this year.

[Cheshire Freeze]

5 minutes ago, feb1991blizzard said:

The OPI looks like it would have recorded a strongly negative value this year.

I suspect we are heading towards a cold and wintry December, all things considered. Not that I place much emphasis on things like the fabled OPI. 

I'm looking and getting 2010 vibes. The output further towards, and during, November will give us more clues.