Model Output Discussion - mid Autumn

[Arch Stanton]

6 minutes ago, carinthian said:

Evening all. The Polar Jet Stream out to this weekend continues  to show a more southerly track than normal with the British Isles on the colder side. Several models have shown developments of  slider low in the vicinity of Southern Britain to move towards the Alps during Sunday as indicated on the chart below. Beyond that the models still ebbing and flowing with a continuation of the prolonged unsettled spell against some form of build in high pressure being more influential to the forecast for Mid - month.  I have a feeling that a rather colder scenario getting established by then. This is mostly based on a continuation of the more southerly tracking jet shown by the models.

C

Unless the near continent gets properly cold then any wintry weather over the SE is usually short-lived. Its good to see Scandanavia cold & very snowy so early on, I'm just praying for a big, immovable Scandi high this winter.

[carinthian]

5 minutes ago, Chasbrown said:

Carinthian, looking forward to your snowy pictures this season. Thanks. 

Hi,  we have snow already and more expected later in the week. I will post pictures in the Austrian Thread when we get the next top up. See you from Gatwick. I lived in Charlwood when I worked at LGW back in the 80s !

C

[carinthian]

5 minutes ago, Arch Stanton said:

Unless the near continent gets properly cold then any wintry weather over the SE is usually short-lived. Its good to see Scandanavia cold & very snowy so early on, I'm just praying for a big, immovable Scandi high this winter.

Late Autumn / Early Winter cold across The British Isles normally establishes from the north rather than the continent. A big immovable Scandinavian High ? Its a long time since one of those sent prolonged cold into the UK. Yes, I prey for one as well. Good for you but not so for the Eastern Alps !

C

[Arch Stanton]

18 minutes ago, carinthian said:

Late Autumn / Early Winter cold across The British Isles normally establishes from the north rather than the continent. A big immovable Scandinavian High ? Its a long time since one of those sent prolonged cold into the UK. Yes, I prey for one as well. Good for you but not so for the Eastern Alps !

C

I live in hope!

[Chasbrown]

1 hour ago, carinthian said:

Hi,  we have snow already and more expected later in the week. I will post pictures in the Austrian Thread when we get the next top up. See you from Gatwick. I lived in Charlwood when I worked at LGW back in the 80s !

C

Appreciate that thanks. I also worked at Lgw until covid killed it.

[WYorksWeather]

Not got time for a full post, so I'll go through the ECM meteograms again. Usual pick of locations - London, Sheffield, Newcastle, Aberdeen.

Again, climate normals for these charts are roughly analogous to 2004-2023.

   

In London, we see below average temperatures for the next five days, then above average after that, then returning closer to the mean. Overall, it probably comes out about average.

Patterns are similar further north, but in Sheffield the cold spell over the next few days isn't really that cold time of year, and it is then an above average picture moving forwards. Newcastle is milder still relative to its average.

Even as far north as Aberdeen, though of course temperatures are lower here in absolute terms, it is still a mild picture, with very few overnight frosts.

A relatively wet picture for most still, though not as much so as of late.

As others have noted, there are some intriguing cold weather patterns potentially setting up for later as we move into winter, but for now, it's mild and showery all the way.

Nothing wrong with taking a day's break from the main models - I'll try to fit a proper post in tomorrow night and take a look at the road ahead in a bit more detail.

 

[January Snowstorm]

The charts don't look great to me at the moment. A strong high pressure over Spain is becoming a feature as we move to mid November. We've seen this many times over the years and how stubborn it can be...

(Excluding gfs of course which is in a world of its own since last years upgrade)

Edited November 8, 2023 by January Snowstorm

[Jordan S]

An incredibly deep area of low pressure modelled by the GFS this morning out over the middle of the North Atlantic. Pressure down to 928mb, weakening and then effecting Iceland, while it won’t effect us at all, it does show the potential conducive environment for explosive cyclogenesis to be prevalent with any systems developing across the Atlantic towards the end of November.

 

For the short term it remains less unsettled than recently with places managing to steadily dry out to some extent, as for tomorrow and especially Friday, not looking as settled as previously thought would be for southern parts of the uk with windy conditions in the south and west of England and Wales as well as further showers with possibly a longer spell of rain swinging southeast for a time early Friday but not amounting to much, showery in the north too but not particularly breezy. 

Weekend as a whole looks mostly dry for northern and eastern parts of the uk, with the risk of frost and fog for a few especially for Scotland, whereas although perhaps dry at first further south , it will turn cloudier with rain moving into southwestern areas later Saturday and then southern areas on Sunday as a low and weather front tries to move through though high pressure developing over Scandinavia helping to delay and disrupt the weather fronts progress east with the large majority of the front slipping into the Low countries.

By Monday/Tuesday next week, these unsettled conditions spreading northeast into Scotland too with the risk of snow on hills here,

becoming windy in the south and west of the UK by the middle of next week with the risk of gales around coasts and gusts to 40-50mph inland moving east along with further rain in some areas possibly heaviest over the vulnerable parts of eastern Scotland with a wraparound weather front bringing the chance of heaviest rain for a time here. but won’t be a washout by any means for the most part elsewhere with on the whole excluding middle of next week the wettest conditions generally still over the south and west of the uk through next week. Turning slightly milder for most. Apart from possibly the far northeast of the uk. With hill snow continuing to be possible in Scotland. 

Into the third week of November 20th to 27th and it’s likely that higher pressure will have more influence over southern areas of England , with more average Synoptics taking hold for a time with wettest and windiest weather over Northern Ireland and Scotland with the risk of gales occasionally and somewhat drier and less windy weather further south with some dry days but still with weakening frontal systems producing more cloud and some drizzle and light rain in the more settled areas on occasion.

 

Gfs as a broad example though this view isn’t based off just the Gfs output.

Perhaps higher pressure slipping back southwest of the uk and higher pressure remaining close to or over Scandinavia, along with a strengthening of the jet stream across the Atlantic in the last few days of November with it becoming colder for most or all as northwest winds possibly more frequent bringing much more unsettled conditions into all areas with the increasing risk of gales in places, these could be severe in places with northern areas most at risk at first anyway.

Rain bands look most likely to move across the country quite quickly so significant flooding as we’ve seen from any one weather system is unlikely but we may see more flooding from just the succession of rain bands. With the possible colder conditions there could be snow to lower levels of Scotland on occasion with hill snow possible in northern areas of England and Wales in heavier precipitation. 

This may lead to a more settled start to meteorological winter with high pressure beginning to influence all areas more through the first week of December with increased fog and frost for some. And drier start to the month for all. But this is a while out of course so we’ll see if that does happen. 

Edited November 8, 2023 by Jordan S

[alexisj9]

12 minutes ago, Jordan S said:

An incredibly deep area of low pressure modelled by the GFS this morning out over the middle of the North Atlantic. Pressure down to 928mb, weakening and then effecting Iceland, while it won’t effect us at all, it does show the potential conducive environment for explosive cyclogenesis to be prevalent with any systems developing across the Atlantic towards the end of November.

 

For the short term it remains less unsettled than recently with places managing to steadily dry out to some extent, as for tomorrow and especially Friday, not looking as settled as previously thought would be for southern parts of the uk with windy conditions in the south and west of England and Wales as well as further showers with possibly a longer spell of rain swinging southeast for a time early Friday but not amounting to much, showery in the north too but not particularly breezy. 

Weekend as a whole looks mostly dry for northern and eastern parts of the uk, with the risk of frost and fog for a few especially for Scotland, whereas although perhaps dry at first further south , it will turn cloudier with rain moving into southwestern areas later Saturday and then southern areas on Sunday as a low and weather front tries to move through though high pressure developing over Scandinavia helping to delay and disrupt the weather fronts progress east with the large majority of the front slipping into the Low countries.

By Monday/Tuesday next week, these unsettled conditions spreading northeast into Scotland too with the risk of snow on hills here,

becoming windy in the south and west of the UK by the middle of next week with the risk of gales around coasts and gusts to 40-50mph inland moving east along with further rain in some areas possibly heaviest over the vulnerable parts of eastern Scotland with a wraparound weather front bringing the chance of heaviest rain for a time here. but won’t be a washout by any means for the most part elsewhere with on the whole excluding middle of next week the wettest conditions generally still over the south and west of the uk through next week. Turning slightly milder for most. Apart from possibly the far northeast of the uk. With hill snow continuing to be possible in Scotland. 

Into the third week of November and it’s likely that higher pressure will have more influence over southern areas of England , with more average Synoptics taking hold for a time with wettest and windiest weather over Northern Ireland and Scotland with the risk of gales occasionally and somewhat drier and less windy weather further south with some dry days but still with weakening frontal systems producing more cloud and some drizzle and light rain in the more settled areas on occasion.

 

Gfs as a broad example though this view isn’t based off just the Gfs output.

Perhaps higher pressure slipping back southwest of the uk and higher pressure remaining close to or over Scandinavia, along with a strengthening of the jet stream across the Atlantic in the last week of November with it becoming colder for most or all as northwest winds possibly more frequent bringing much more unsettled conditions into all areas with the increasing risk of gales in places, these could be severe in places with northern areas most at risk at first anyway.

Rain bands look most likely to move across the country quite quickly so significant flooding as we’ve seen from any one weather system is unlikely but we may see more flooding from just the succession of rain bands. With the possible colder conditions there could be snow to lower levels of Scotland on occasion with hill snow possible in northern areas of England and Wales in heavier precipitation. 

This may lead to a more settled start to meteorological winter with high pressure beginning to influence all areas more with increased fog and frost for some. And drier start to the month for all. But this is a while out of course so we’ll see if that does happen. 

Yuk looks like a repeat of the pattern we just had, a low stuck due to a high in the north east dropping lots of rain on the south coast and Scotland from the east. Not good.

Edited November 8, 2023 by alexisj9

[Jordan S]

41 minutes ago, alexisj9 said:

Yuk looks like a repeat of the pattern we just had, a low stuck due to a high in the north east dropping lots of rain on the south coast and Scotland from the east. Not good.

Broadly similar but as a whole looks drier for those areas of eastern Scotland and eastern England compared with the last couple of weeks, with rain generally moving through quicker through those especially hard hit areas so although not settled and wet at times here it thankfully doesn’t look extreme or as wet as elsewhere. does look much wetter for the south and west UK compared to elsewhere like I said above through next week as a whole. But hopefully a trend for drier weather developing for the southern half of the country in the following week.

An example of this below..

Edited November 8, 2023 by Jordan S

[ItNeverSnowsInWindsor]

Just wish the North Atlantic drift would shut down to give us a break from all the mild mush!

[ANYWEATHER]

13 minutes ago, prolongedSnowLover said:

Just wish the North Atlantic drift would shut down to give us a break from all the mild mush!

No you wouldn't!  Do you know the implications if that would happen?

[TSNWK]

12 minutes ago, prolongedSnowLover said:

Just wish the North Atlantic drift would shut down to give us a break from all the mild mush!

No thanks.. unless you want 6 months of sub zero and meters of snow from November to April..  labrador climate..  

[MattStoke]

Just now, TSNWK said:

No thanks.. unless you want 6 months of sub zero and meters of snow from November to April..  labrador climate..  

Yes please. 

[Aiden2012]

7 minutes ago, TSNWK said:

No thanks.. unless you want 6 months of sub zero and meters of snow from November to April..  labrador climate..  

exactly what we want

[northwestsnow]

5 minutes ago, TSNWK said:

No thanks.. unless you want 6 months of sub zero and meters of snow from November to April..  labrador climate..  

It's hardly stopped raining here for weeks and by the looks of it we can expect another 3 weeks bar the odd day here and there.

This is Shaping up to be the worst Autumn ever locally hardly a dry day to appreciate mother nature at her best .

00z runs are just awful and reading matts thoughts in the winter thread it's going to go on and on.

[mathematician]

1 hour ago, TSNWK said:

No thanks.. unless you want 6 months of sub zero and meters of snow from November to April..  labrador climate..  

Where do I sign?

[StretfordEnd1996]

Amidst the soaking weather recently (for me anyway) and the recent gloomy weather and somewhat gloomy outlook at least it looks like we can nick a settled chilly night for the majority of the country back end of this week



Not that it's a sign of things to come thereafter

[Tamara]

15 hours ago, Metwatch said:

In the more closer time frame there is an interesting phenomenon, which although it affects us less, I still think it's important to some extent. That is the 'Summer of San Martin.'

Essentially it's a few day period in mid November, starting around the 11th where conditions settle down for Iberia as high pressure builds more compared to October / early November, and it often happens most years; the data has been analysed to prove it during this period in the year. It's a sort of Indian summer if you like.

We see it this year with the ECM height anomaly. Heights in Spain (sort of Euro heights if they move more north in some years) usually keep the UK under a zonal flow, so it remains unsettled and it can be on the mild side. Spain is often under high pressure a lot of the time as it is on the border between the Hadley and Ferrel cell with descending air and close to the Azores high, but even so this seems to stand out more. Mid November 2015 was the biggest example of the quirk.

Not sure if it's the MJO, GWO or AAM etc that causes this, probably a multitude of teleconnections working together in the background which coincide themselves for mid November. I am curious if @Tamara who is in southern Portugal would notice this perhaps where it's called 'Verão de São Martinho.'

If you would like to read more about it, an article below:

Know everything about the summer of San Martín | Network Meteorology

WWW.METEOROLOGIAENRED.COM

---

In this article we tell you all the secrets, curiosities and we explain why the summer of San Martín is formed. Come in and find out.

Thanks for posting that link - its a very interesting background to the phenomenon

The ECM in particular advertises a classic Verão de São Martinho for this part of the southern Europe from the weekend and extends it well through next week. The rains have been welcome easing the drought (though the Algarve & Alentejo need a lot more rain). But some late autumn sun & temperatures into the low 20s will be much appreciated

 

 

[Jacob]

3 hours ago, TSNWK said:

No thanks.. unless you want 6 months of sub zero and meters of snow from November to April..  labrador climate..  

Well I want that lol

[Don]

3 hours ago, mathematician said:

Where do I sign?

When you find out, let me know too!  

[Downburst]

Looking at the 46 day charts and it's most likely NAO + to end of month into early December. 

I fact it looks very much the same well into December

Come on and do something weather, want a rest from the rain.

[TSNWK]

Gfs toying with a little something around day 9.. still no vortex setting up to north west..

this chart would be pretty chilly..

Edited November 8, 2023 by TSNWK

[Dancerwithwings]

06z GEFS member 11 has been on the pop methinks

[Rain All Night]

15 minutes ago, TSNWK said:

Gfs toying with a little something around day 9.. still no vortex setting up to north west..

this chart would be pretty chilly..

The ECM, GFS and GEM ensembles have all been consistently showing height rises from the south around that date, though not many individual member runs show as optimistic a solution as this one on the scale of those heights.