Model Output Discussion 01/09/17

[Seasonality]

18 hours ago, damianslaw said:

Yes we appear to be starting this autumn on a very different note to many recent ones, with a much more active atlantic and cooler arctic, which is likely to result in much stronger low pressure systems with more advanced temp gradients, hence a potentially much stormier season than of late. Last autumn was so benign it barely got going. The early September high pressure spell is dead this year.

Next week looks very unsettled with a strong atlantic flow, then a possible deep low pressure system next weekend bringing early gales and some quite chilly air, it will feel more like late October.

Looking further ahead, we could see a more settled quiet spell as we approach mid month, with ridge development to our west anchoring itself across the country, but I suspect it will be shortlived with further atlantic gusto behind it - this could be the theme of the autumn, very unsettled wet stormy cool weather interspersed with shortlived quieter settled conditions, at least through Sept and October. November I feel could be a bit more different.

Do tell!

[Summer Sun]

3 models for Sunday 12z and all 3 handle the low differently

[Summer Sun]

GEM is finding a different route today with pressure starting to rise during Tuesday and Wednesday

[Timmytour]

2 minutes ago, Summer Sun said:

GEM is finding a different route today with pressure starting to rise during Tuesday and Wednesday

Would that low be the remnants of Irma?   Wouldn't be surprised to see it smashing through the way our luck has been going lately and deliver another bout of horriblenesss towards the end of next week!

[Summer Sun]

1 minute ago, Timmytour said:

Would that low be the remnants of Irma?   Wouldn't be surprised to see it smashing through the way our luck has been going lately and deliver another bout of horriblenesss towards the end of next week!

If it is GEM takes it to the north of the UK bringing strong winds and rain to the far north but also some warmer air so the further south and SE you are it would be feeling quite warm

[knocker]

1 hour ago, Timmytour said:

Would that low be the remnants of Irma?   Wouldn't be surprised to see it smashing through the way our luck has been going lately and deliver another bout of horriblenesss towards the end of next week!

No this would have arrived from the N.Canada/ Greenland route Irma is still in the SE of the States.Assuming I have the correct low

Edited September 4, 2017 by knocker

[Frosty.]

Wow the Gfs 12z out to around T+240 hours attracts vigorous atlantic depressions to the uk like bees to a honeypot, very unsettled with lows occasionally merging bringing plenty of wet and windy weather with generally rather cool temperatures..further into low res there is a slight improvement with winds easing but overall it's an unsettled autumnal run with some hazardous weather likely across the uk at times from later this week and throughout next week according to this run..certainly not boring!

Edited September 4, 2017 by Frosty.

[Ice Man 85]

2 hours ago, CreweCold said:

Actually, N Atlantic blocking as shown above is exactly what I want to see. There is a historic correlation between this blocking in September and N blocking during winter. 

Agreed. Anything that keeps the Azores High away is a blessing.

[Summer Sun]

The weekend and early next week is still causing the models a headache

00z

12z

 

[knocker]

The ecm this evening has the first low sweeping east and the fronts impacting the north west by 12z Thursday. In the next 24 hours they track across the country inti Denmark and N. Germany with the low centred over Thurso and plunging the UK in a cool, showery, north westerly.

The low then drifts east into the North Sea thus the surface wind veering northerly  But this is short lived as the next intense low is rapidly approaching from the WNW and by 06z Sunday is north west of Ireland 978mb. By 18z it's smack over the North of England bringing heavy rain although the strongest winds may well be in the southern quadrant over France.

It continues to track east but some more fronts swing into the south west Tuesday morning.

[Man With Beard]

Evening all, well I was going to take my time over repairs to my shed, but I think I'll bring my plans forward! ECM clusters this morning did not provide much hope of a way out from this storm, and the south coast looks the most vulnerable right now.

[knocker]

No significant changes with last evening’s anomalies so the medium range outlook remains as previously stated. Perhaps the UK trough and mid Atlantic high pressure nudging a tad east as expected.

So on to more pressing matters and the upcoming weather which is concentrating minds. Quite an active front crossing the country today with some quite heavy bursts of rain in it’s proximity and weather in your area is dependent on whether you are east or west of it.

Wednesday a much better day although still a fairly healthy westerly with some showers in the north before the deterioration sets in on Thursday. By midday the new low is between Iceland and Scotland with the associated fronts already impacting N. Ireland and western Scotland. These track quickly ESE and by midday Friday the low is over the Hebrides 987mb with the UK in a showery north westerly, perhaps also some longer periods of rain. A classic scenario with the high pressure pushing north in mid Atlantic

The centre of the low drifts away to the North east over Saturday leaving the UK in a cool, showery, northerly with perhaps the odd perturbation developing in the circulation but this is just the prelude to the next visitation from the WNW. By 12z Sunday the next low 975mb is south of Iceland with the fronts impacting the north west This quickly develops as it merges with the old low and by 06Z Monday we have an intense feature 977mb over western Scotland which swings east into the North Sea and fills during the day. Depending precisely how this develops it could bring strong winds and heavy rain in some places for a time but I suspect this is still a long way from being done and dusted

Edited September 5, 2017 by knocker

[mb018538]

Thanks knocker.

Unless there is a marked change around the middle of the month, we could be gearing up for one of the most unsettled Septembers in recent years. Any thoughts of a late summer heatwave are receding by the day, and it will feel distinctly autumnal by the time that big low sweeps in at the end of the week, and possibly even cool to cold into the following week as winds veer round to the north. Perhaps the first proper frost could be on the way?

[mushymanrob]

1 minute ago, mb018538 said:

Thanks knocker.

Unless there is a marked change around the middle of the month, we could be gearing up for one of the most unsettled Septembers in recent years. Any thoughts of a late summer heatwave are receding by the day, and it will feel distinctly autumnal by the time that big low sweeps in at the end of the week, and possibly even cool to cold into the following week as winds veer round to the north. Perhaps the first proper frost could be on the way?

well that would give some credence to a reported met offices 'indian summer' likely. its certainly looking cool/below average and we could get some very low overnight temps.

[mountain shadow]

23 minutes ago, mb018538 said:

Thanks knocker.

Unless there is a marked change around the middle of the month, we could be gearing up for one of the most unsettled Septembers in recent years. Any thoughts of a late summer heatwave are receding by the day, and it will feel distinctly autumnal by the time that big low sweeps in at the end of the week, and possibly even cool to cold into the following week as winds veer round to the north. Perhaps the first proper frost could be on the way?

It's been Autumnal here for the last two months.

Models firming up on more of the same. Harvest could be washed away. 

[knocker]

The ecm this morning has the second low 980mb SW of Iceland at Sunday 00z. twenty four hours later it is over Scotland bringing with it some heavy rain for a time and westerly gales, possible severe, in the southern quadrant over England. It then clears east to be over southern Norway by 00z Tuesday leaving the UK in a showery NNW airstream.

 

[Summer Sun]

UKMO and ECM are almost is perfect agreement for the UK at t144

 

Edited September 5, 2017 by Summer Sun

[Summer Sun]

I don't think I've ever seen the ECM London pressure ens in such close agreement for the entire 10 day period

[legritter]

Good morning Gang ,I have been Lurking around following most posts over the last few months ,but with my beautiful wife being diagnosed Terminal C ,about 4 months ago .Anyhow ,looking at the Charts it looks like a very mixed bag of weather coming up soon ,to early for loads of detail but several low pressure systems diving across our shores ,for those that dont like it too wet though ,perhaps the azores high may help you out a bit especially later in the upcoming period ,and of course the models may get the wobbles depending on any EX hurricanes ,and where all their left over energy finishes up .Cheers GANG ,is it time to get out the hat ,gloves and scarf .

[cheshire snow]

5 minutes ago, legritter said:

Good morning Gang ,I have been Lurking around following most posts over the last few months ,but with my beautiful wife being diagnosed Terminal C ,about 4 months ago .Anyhow ,looking at the Charts it looks like a very mixed bag of weather coming up soon ,to early for loads of detail but several low pressure systems diving across our shores ,for those that dont like it too wet though ,perhaps the azores high may help you out a bit especially later in the upcoming period ,and of course the models may get the wobbles depending on any EX hurricanes ,and where all their left over energy finishes up .Cheers GANG ,is it time to get out the hat ,gloves and scarf .

That's awfull news Legritter thoughts to you and your family,keep strong and keep posting,I am sure I speak for all,when saying the whole of net weather community are with you.

C.S. 

Edited September 5, 2017 by cheshire snow

[Summer Sun]

GFS shows low pressure moving down the country during Sunday and into Monday

This then begins to pull away for Tuesday allowing pressure to rise a bit in the south and the rain begins to turn more patchy

Edited September 5, 2017 by Summer Sun

[johnholmes]

1 hour ago, legritter said:

Good morning Gang ,I have been Lurking around following most posts over the last few months ,but with my beautiful wife being diagnosed Terminal C ,about 4 months ago .Anyhow ,looking at the Charts it looks like a very mixed bag of weather coming up soon ,to early for loads of detail but several low pressure systems diving across our shores ,for those that dont like it too wet though ,perhaps the azores high may help you out a bit especially later in the upcoming period ,and of course the models may get the wobbles depending on any EX hurricanes ,and where all their left over energy finishes up .Cheers GANG ,is it time to get out the hat ,gloves and scarf .

That is awful news L, My thoughts and I am sure everyone on here is with you and your wife. Have you asked for support to you both from Macmillan Nurses, they help with all the problems you will be facing?

 

[Man With Beard]

can i echo the comments above by JH / CS

ECM clusters this morning - still with some even more disturbed options than shown by the op

[Summer Sun]

Based on the 00z GFS output the south won't see much main over the next week

Edited September 5, 2017 by Summer Sun

[Summer Sun]

UKMO 12z has the centre of the low near Denmark at 12z Monday leaving the UK in a fresher northerly flow

GFS has the centre over NE Holland / NW Germany

Temps ranging from 10c in northern Scotland to 18c in the SE