Model Output Discussion - mid Autumn

[Summer8906]

3 minutes ago, TwisterGirl81 said:

Any kind of weather can kill, this is a weather forum 

21C, partly cloudy skies, calm and dry in May?

Edited October 29, 2023 by Summer8906

[Wivenswold]

Just now, Summer8906 said:

21C, partly cloudy skies, calm and dry in May?

8 hours in that strong sunshine without sun block could cause problems. Not to mention more people out on the roads. 

[Summer8906]

3 minutes ago, Wivenswold said:

8 hours in that strong sunshine without sun block could cause problems. Not to mention more people out on the roads. 

Hence "partly cloudy skies". Thinking of those kinds of late spring days with about 4/8 cloud cover, rather than continuous sunshine.

Or alternatively, how about mild and sunny in Feb?

Or cloudy, dry and calm with unremarkable temps at any time of year? Boring, perhaps, but completely harmless.

Edited October 29, 2023 by Summer8906

[Wivenswold]

More gardening and DIY accidents in fair weather. 

Sorry mods, this is really going off the rails, but some humour ahead of a big storm isn't a bad thing. 

[Josh Rubio]

The ‘enthusiastic’ side of me hopes this will trend to head back on a more northerly path, although I do understand dangers and consequences of the impacts possible. 

[WYorksWeather]

We all have our weather preferences. Weather can be potentially dangerous but also exciting / interesting for some. Any extreme conditions have the potential to cause significant property damage or loss of life - be it a prolonged sub-zero spell, heavy rain, storms, extreme heatwaves, and so on.

The key is to appreciate the power or excitement associated with the weather, but to still be human enough to have sympathy for those that are affected. This forum would be extremely dull after all if nobody got excited when something unusual happened! But it'd also be quite a sad place if we just told anyone concerned about an extreme weather event where to go. It has to be a balance.

To prevent this from going too far off topic, here's the ECM ensemble mean.

[matty40s]

Anyone in the Bay of Biscay later this week will need a strong stomach

 

The accumulated rain for the week...

 

 

[alexisj9]

6 minutes ago, WYorksWeather said:

We all have our weather preferences. Weather can be potentially dangerous but also exciting / interesting for some. Any extreme conditions have the potential to cause significant property damage or loss of life - be it a prolonged sub-zero spell, heavy rain, storms, extreme heatwaves, and so on.

The key is to appreciate the power or excitement associated with the weather, but to still be human enough to have sympathy for those that are affected. This forum would be extremely dull after all if nobody got excited when something unusual happened! But it'd also be quite a sad place if we just told anyone concerned about an extreme weather event where to go. It has to be a balance.

To prevent this from going too far off topic, here's the ECM ensemble mean.

I haven't looked at the mean, wonder if the pressure is falling with each run, or whether it seems to have found a level,does anyone know, not looking at just ecm specifically. In these situations watch what the mean is doing with the low over time, can give some insite.

[IDO]

Looking at the mean wind, we can see the usual trend of the system(s) being modelled further south as we get nearer the event(s). GFS 06z mean:

[Captain Shortwave]

We were due a stormy mid-autumn, that said the coming period isn’t really that normal given we are seeing stormy conditions at the same time as seeing heights omnipresent to our north. 
The storm for Thursday looks like a tough one to model given it will deepen and then dumbbell around the parent low before becoming one discreet system. At the moment it could bring severe winds anywhere from the middle of France to northern England, on the other hand it could become absorbed into the parent low quicker and not be so much of a problem.

Rain looks being the more definite problem, even today there is a near endless supply of moisture pushing out of the English Channel and with low pressure tracking further south compared to normal, then England and Wales look like baring the brunt of the rain in the coming days.
 

[tight isobar]

hi-  well I come bk in for the autumn/ winter, on the cusp of perhaps some news making weather!.  As alluded - we have some critical Atlantic energy’s spawning from the usual US seaboard into the pond, hand in hand on a more or less srting jet scenario.    Keeping things short for the here n- now, it’s an obvious evolving point/ points. However as often we see the modeling when running into a nearer time base- up- and downing LPS as output start’s nearer deciphering.  And as often we see the biscay boomerang  being a plot for modeling in the mid term…. It’s the shorter prognosis “ that obviously “- needs consideration- As there is some real possibilities for some excessive/ Damaging weather in hand … Anyway we do what we do and watch such dramas unfold!!.  Good to be bk , And let’s see where we go this season

Edited October 29, 2023 by tight isobar

[Buzz]

35 minutes ago, IDO said:

Looking at the mean wind, we can see the usual trend of the system(s) being modelled further south as we get nearer the event(s). GFS 06z mean:

Yup, at the moment it does seem to be trending south - good for the UK but of course very bad for France.

I just hope that it's not nearly as strong as currently forecast so that nobody has to suffer from potentially highly damaging winds.

I know that some love extreme weather but as people grow up and mature most of us come to realise that what is often classed as 'exciting' weather is usually damaging to both life and property, plus a lot of harm is caused by the inevitable power cuts. Only those who are aware of the damaging potential yet who are also selfish and/or mean-spirited could possibly even entertain the idea of enjoying something which would harm others, whether that is weather-related or otherwise.

Edited October 29, 2023 by Buzz

[daniel barber]

36 minutes ago, IDO said:

Looking at the mean wind, we can see the usual trend of the system(s) being modelled further south as we get nearer the event(s). GFS 06z mean:

There's going to be some pretty big storm surge totals in France from that

[Metwatch]

20 hours ago, Metwatch said:

Dartboard low if if i've ever seen one from tonight's ECM, UKMO similar next Thursday too.

Might need to check up on some pressure records here, if it gets close to 950hPa would surely be close to or even a new low atmospheric pressure record for November.

So the lowest all time pressure here is 960 hPa which was in 1989, but for November the lowest is 966 hPa during November 2010, with records going back to 1977, so not that long.

What this means is that it shows how extreme in the climatology this is for so far south in the UK in early November. Probably a lot more worrying for northern France rather than England if the storm continues to trend southward.

Finally found the site which shows this (linked below), and yes record low in the MSLP percentile rank for Thursday, and also again on Saturday.

http://arctic.som.ou.edu/tburg/models/?model=gfs&base=percentile_mslp&background=plain&state=states_brown&country=countries_brown&proj=eur&archive=false&run=2023102906

 

Edited October 29, 2023 by Metwatch

[Downburst]

2 hours ago, Summer8906 said:

21C, partly cloudy skies, calm and dry in May?

That’s what your hard core weather want’s you to think.

[January Snowstorm]

Icon nudges North, severe winds off South Coast UK

[Lakigigar]

20 hours ago, Metwatch said:

Dartboard low if if i've ever seen one from tonight's ECM, UKMO similar next Thursday too.

Might need to check up on some pressure records here, if it gets close to 950hPa would surely be close to or even a new low atmospheric pressure record for November.

These are the records for all of the UK, but this is more to the south than those.

For all-time records:
Lowest: 22 November 1865, Dolgellau, North Wales 944.8 hPa.
Lowest: 8 December 1886, Stonyhurst in Lancashire, where the barometer fell to 940.4 hPa.

It's also possible that the 19th century records aren't in the database.

Great Storm of 1987 got down to 953 hPa in the North Sea. And the 2000 storm named cyclone Oratia reached 941 hPa according to peer review data but that one was more to the northeast with the record set on sea (and not officially recorded, but reconstructed).

[richie3846]

Just now, Lakigigar said:

These are the records for all of the UK, but this is more to the south than those.

For all-time records:
Lowest: 22 November 1865, Dolgellau, North Wales 944.8 hPa.
Lowest: 8 December 1886, Stonyhurst in Lancashire, where the barometer fell to 940.4 hPa.

It's also possible that the 19th century records aren't in the database.

Great Storm of 1987 got down to 953 hPa in the North Sea. And the 2000 storm named cyclone Oratia reached 941 hPa according to peer review data but that one was more to the northeast with the record set on sea (and not officially recorded, but reconstructed).

Record low pressure of February 25th 1989 | Wanstead Meteo

WANSTEADMETEO.COM

---

The low pressure system that brought widespread rain and snow on Wednesday reminded me of another event where very low atmospheric pressure...

If this document is correct, this is another notable low pressure, interesting that it happened only 16 months after the 1987 storm. 

[Lakigigar]

4 minutes ago, richie3846 said:

Record low pressure of February 25th 1989 | Wanstead Meteo

WANSTEADMETEO.COM

---

The low pressure system that brought widespread rain and snow on Wednesday reminded me of another event where very low atmospheric pressure...

If this document is correct, this is another notable low pressure, interesting that it happened only 16 months after the 1987 storm. 

Lowest air pressure: 25 February 1989, Jersey 953.8 hPa (Jersey)
Lowest air pressure: 25 February 1989, Guernsey 952.5 hPa. (Guernsey)
Lowest air pressure: 25 February 1989, Cap de La Hague, Cherbourg 951.8 hPa. (France)
Lowest air pressure: 25 February 1989, Blankenberge 954 hPa (Belgium)
Lowest air pressure: 25 December 1821 Boulogne sur mer 947.1 hPa. (France, not official)

I got those records for the channel islands, France and Belgium. Most are indeed of that day.



The UKMO chart is definitely around those levels for the second one (saturday storm)

Edited October 29, 2023 by Lakigigar

[Metwatch]

15 minutes ago, Lakigigar said:

These are the records for all of the UK, but this is more to the south than those.

For all-time records:
Lowest: 22 November 1865, Dolgellau, North Wales 944.8 hPa.
Lowest: 8 December 1886, Stonyhurst in Lancashire, where the barometer fell to 940.4 hPa.

It's also possible that the 19th century records aren't in the database.

Great Storm of 1987 got down to 953 hPa in the North Sea. And the 2000 storm named cyclone Oratia reached 941 hPa according to peer review data but that one was more to the northeast with the record set on sea (and not officially recorded, but reconstructed).

 

11 minutes ago, richie3846 said:

Record low pressure of February 25th 1989 | Wanstead Meteo

WANSTEADMETEO.COM

---

The low pressure system that brought widespread rain and snow on Wednesday reminded me of another event where very low atmospheric pressure...

If this document is correct, this is another notable low pressure, interesting that it happened only 16 months after the 1987 storm. 

Incredible how this could be challenged so early in the windstorm season in early November, been a while since a lot of the very low pressure records, with a lot of them 60 years ago, to even a century or longer ago!

[TwisterGirl81]

3 hours ago, Summer8906 said:

21C, partly cloudy skies, calm and dry in May?

23c and we’re good

[Kirkcaldy Weather]

On 26/10/2023 at 21:18, Kirkcaldy Weather said:

I posted the following September 19th 

What could unfold as we go into October?

These are the biggest development dynamical situations I'd be expectant to be occuring. Hazarding a date keep eyes around later of October Week 2 sometime around 10th - 13th

Elongation of European Heights start a gradual movement evolving to Scandinavia---Greenland 

New trough emerging close by most probably a smidge to the East then drifting to the UK 

I'm noticing that trend of low pressures through the United States trends show that eastern coastal Noreaster style as a possible setup

And the following 500hpa animation on 8th of October 

 

New 500hpa sequences following that period which go excellent to my thoughts back in September 

 

'Active West Pacific signals [super typhoon Bolaven]

Californian >> Mexican cyclonic pattern. Major Hurricane Lidia plus Tropical Storm Max. Also the potential next Rossby Wave via Bolaven into new California Cyclonic conditions 

Build of pressure through the UK and Scandinavia which transpires as the Rossby Wave within Atlantic continues its progression further East'

Nothing short of spectacular the manner in which this has really energized the setup pretty much globally 

Using the above JMA phase 7 expectant setups it even gave good indication on the -PNA east American high plus the dual zones over on the western end more on this in a minute 

Really stunning showcase of how a positive PNA swaps to that of a negative phase

"an upper trough trying to align on a negative tilt which might see a severe weather event into the Midwest and west central America as that has the energy from Norma which did indeed move into Baja'

Focusing more at the California Baja >> Mexican troughing this really kicked into life from phase 6 but in particular 7 and 8 we've seen Lidia Max Norma and Otis within like 2 weeks.

Crazy.

Next focus is with the separate trough swinging through the Northwest and Canada the recorded temp differences from AVG are truly incredible already with upto and over 30 DEGREES BELOW AVERAGE

 

 

As the PNA rises this will coincide with these values moving east southeastwards with nearly all of America below average and decently at that, I expect a good number of further minimum temperatures will be at and setting new records particularly in traditional warmer states such as Texas and along the Gulf. Might be some high temp records doing the same within that -PNA high initially however the minimum values really are the main news.

A rare pattern by the very beginning of November in regards to a legit cut off Greenland High, a VERY rare beast bringing back the 09/10 vibes. Note the separation of energy has occurred as our block from Scandi has split with the formation further east connecting through Alaska and the Pacific Northwest with the rest over Greenland as discussed and something I mentioned on October 8th

'I'm eagerly awaiting the approach into Halloween  be looking particularly toward the patterns getting retrogressive in nature with scope for further blocking which looks to have the opportunities of origin towards Scandinavia'

Nice viewing as the composites are starting to show in alignment to the continuing phase 8-1 snailpace MJO movement 

We'll have to keep very alert for week 1 November of the forming CAG with very early signals this has possible connections for the PNA moving once again to positive territory, Florida maybe Gulf states need to be mindful with formation currently signalled by November 4th

This lead up to Guy Fawkes gives another date for cyclone development for us also around 2nd - 6th 

 

On 23/10/2023 at 20:07, Kirkcaldy Weather said:

 

We have two dates to really focus in on which are 27th October and 29th October I expect Sunday 29th will have greater impacts for multiple reasons however Friday shouldn't be completely dismissed.

By the 26th and 27th we will have a main cyclone to the west of Ireland - UK which begins the phase of elongating in structure. Downstream dynamical situations will be a Rossby Wave begin the breaking sequence with Tammy and the High connecting with the -PNA with an upper trough trying to align on a negative tilt which might see a severe weather event into the Midwest and west central America as that has the energy from Norma which did indeed move into Baja 

I've deliberately marked an emerging trough from Canada at that stage as this will be a big factor through the start of the developments for the weekend as it ejects through the Labrador Sea

As the trough energies move on the southern flank of our elongating cyclonic structure the two eventually begin the merge into the weekend 

Another huge reason for rapid deepening and strong cyclogenisis will lie with the next major moon phase with the Hunters Full Moon

"One of the worst hurricanes to ever make landfall in North Carolina was Hurricane Hazel in 1954. It made landfall as a Category 4 with estimated 140 mph winds. Hurricane Hazel arrived in October, making it a fairly late-season hurricane. The full moon at the time caused one of the highest lunar tides of 1954 in North Carolina.

There were also concerns about Hurricane Sandy and whether the full moon was going to make that storm worse for residents all along the East Coast. The storm made landfall on October 29 in New Jersey, and October 29 just happened to be when the moon was waxing to its full phase. Estimates suggested tides along the Eastern Seaboard would be about 20 percent higher than normal.

The full Hunter’s Moon peaks on Saturday, October 28, 2023. As with last month’s full Moon, the Hunter’s Moon rises around the same time for several nights, so start looking for it on Friday, October 27!'

'We'll have to keep very alert for week 1 November of the forming CAG with very early signals this has possible connections for the PNA moving once again to positive territory, Florida maybe Gulf states need to be mindful with formation currently signalled by November 4th

This lead up to Guy Fawkes gives another date for cyclone development for us also around 2nd - 6th'

'We have two dates to really focus in on which are 27th October and 29th October I expect Sunday 29th will have greater impacts for multiple reasons however Friday shouldn't be completely dismissed.'

Very pleased with development fitting really good with the above

I can say with a high degree of certainty there are 2 dates with deep cyclones which will have significant impact for the UK and France particularly Northern France 

1. November 2nd
2. November 4th

Looking in detail how each day develops downstream

The deep cyclonic conditions moving across on the 2nd lies with the snowstorm currently impacting Colorado

 

Even as it exits toward Long Island it already contains an energising Jet streak along its southern flank, same timing sees the wave break I discussed previously in regards to Tammy which splits some energy and generates a new low a few miles to its east, importance within a new low which sets up close to Florida plus the next surge of tropical energy into the far East Pacific 

Ive posted the patterns during phases 8 and 1 during November however this is superb as the trough location ties really great

Halloween ^^^

Note there is an active cyclonic activity through the Labrador Sea which inputs towards our cyclone on November 2nd however less of a contributor than the snowstorm.

More incredible stuff happens on Late Halloween eve and especially November 1st which will see the RARE cut off Greenland High as mentioned above, 

So come Halloween we've the Snowstorm moving into the Atlantic, a high energy upper trough swinging from Canada into the Great Lakes creating the first big Lake Effect event (Tug Hill doing nice from this one i expect) there plus the Labrador Sea cyclone feeds enough energy and forms a cyclone west of Ireland

We begin seeing the Florida low better by then also and these two events will be the key for the cyclogenisis for us into November 4th

November 2nd

Snowstorm undergoing rapid deep cyclogenisis and becomes the main cyclone as the energy merge occurs to the smaller cyclonic centre west of Ireland. Pretty rapid deepening involved with our far East Pacific system also. Floridian trough pairing to the Great Lake upper trough. Beginning development showing into our CAG zone

On 21/10/2023 at 21:18, Kirkcaldy Weather said:

This is likely linking with our configuration into November with further energies from it feeding into further Atlantic RWBs with renewed unsettled and most probable STORMY patterns prevailing 

November 4th

• CAG action kicks into life
• New cyclone crossing a similar path and strong cyclogenisis once more

Entire sequence of activities

 

 

[sunnijim]

2 minutes ago, Halfamilefromnowhere said:

Whoops Sleety forgot you are not allowed to express an independent opinion,must adhere to the sensible viewpoint

Think more to do with a weather viewpoint,adhering to a sensible pont of view doesn't count on here when it comes to the mother of all blizzards!

There doesn't seem such an appetite for wind storms, although I love them.

The more favoured with folk here ( snow) can of cause just as much danger to life.

[Norrance]

Please get back to the models. Any more off topic posts will be deleted. Also please read the forum rules about guilt tripping.

[MattStoke]

1 hour ago, sunnijim said:

Think more to do with a weather viewpoint,adhering to a sensible pont of view doesn't count on here when it comes to the mother of all blizzards!

There doesn't seem such an appetite for wind storms, although I love them.

The more favoured with folk here ( snow) can of cause just as much danger to life.

Snow is interesting. Wind and rain just isn’t, and we get it 90% of the year anyway.