Model Output Discussion - Into Summer 2020.

[Allseasons-Si]

UKMO at 144.

could be thundery from the south.

Edited June 7, 2020 by Allseasons-si

[Singularity]

 

A south-westward adjustment of a hundred miles or so, but a slightly stronger low to compensate.

At least it will be a tad warmer Fri-Sat. Or at least, it should be - this is GFS after all!

It's an unusually moisture-laden airmass out to our southeast by this point. Sourced from the eastern Mediterranean, as far as I can make out. Hence all the rainfall in the modelling even when the lows aren't directly involved.

Worth bearing in mind, though, that GFS will tend to 'smooth out' convective features, resulting in a cloudier, less interesting look to the rainfall charts. ECM is not as prone to this but still can't rival a high-resolution shorter-range model like HIRLAM or ARPEGE... though even they still do a bit of smoothing.

[Zak M]

A good end to the 12z UKMO for convective lovers - storms possible on day 6

Edited June 7, 2020 by Zak M

[northwestsnow]

UKMO looks very warm as we draw up SE winds at 144?

I can see the trough causing a few headaches for the models over the next few days though..

[mb018538]

Just now, Zak M said:

A good end to the 12z UKMO for convective lovers - storms possible on day 6.

Was just going to say - 12c uppers into east Anglia by then, and 8-10c widely. Humid.

[Methuselah]

GFS 12Z op is good for Day 5 -- warm, humid and thundery weather incoming:

    

 

[MikeC53]

3 minutes ago, Ice Day said:

This GFS run is a bit of a rainmaker, certainly for the south out to 102 

Cumulative rainfall has increased vs its previous run also, with some fairly large totals now showing up by Friday morning, with Central Southern England seeing the most at this point.

Yes two days of continuous heavy rain for here at least.

[northwestsnow]

1 minute ago, mb018538 said:

Was just going to say - 12c uppers into east Anglia by then, and 8-10c widely. Humid.

Warm,humid, thundery perhaps...

Continental-esq...

[MikeC53]

Cornwall and Devon especially are looking at serious flooding on this run.

[mb018538]

1 minute ago, MikeC53 said:

Cornwall and Devon especially are looking at serious flooding on this run.

Could well be. Looks like the low wants to wander down to the SW of the UK, so they’d be in prime position for most exposure to the frontal rain.

[Djdazzle]

Just now, mb018538 said:

Could well be. Looks like the low wants to wander down to the SW of the UK, so they’d be in prime position for most exposure to the frontal rain.

Hoping it ends up further west as per the thoughts of some on here.

[MikeC53]

1 minute ago, mb018538 said:

Could well be. Looks like the low wants to wander down to the SW of the UK, so they’d be in prime position for most exposure to the frontal rain.

Day 7 and its still raining in the far SW.

[SMU]

Very pleased with UKMO day 6

+12c Isotherm arriving from the SE poss thundery however the evolution could pave the way for continental heat...

[Mike Poole]

GFS T162:

The thing to watch I think on this run and the GEM and ECM to come is whether the low near us and the one south Greenland link.  This will allow the high to ridge from the Azores to Scandi albeit initially with an obstacle in the way, this was the evolution on that ECM parallel run I posted earlier, and I think it is the likely evolution, and will lead to hot but likely sporadically unsettled weather as we go forward.  Just my musings, of course. We will see...

Edited June 7, 2020 by Mike Poole

[Man With Beard]

10 minutes ago, Allseasons-si said:

UKMO at 144.

could be thundery from the south.

That would be a very interesting position. Except perhaps for the SW, the UK has got onto the right side of the trough for warm weather, and may have escaped any organized rain bands. It may well be a thunderstorm maker. Would like to see a few more charts of this! 

[northwestsnow]

Just now, Steve Murr said:

Very pleased with UKMO day 6

+12c Isotherm arriving from the SE poss thundery however the evolution could pave the way for continental heat...

Very hot in Poland/Belarus/Western Russia on GFS!!

If the low stalls to our SW that heat could be heading here..

[Allseasons-Si]

1 minute ago, Man With Beard said:

That would be a very interesting position. Except perhaps for the SW, the UK has got onto the right side of the trough for warm weather, and may have escaped any organized rain bands. It may well be a thunderstorm maker. Would like to see a few more charts of this! 

It's a beauty of a chart for heat and storms but i suspect that it will be handled differently nearer the time,could be further west and we would have a true plume from the south,all good model watching at the moment.

[Singularity]

  

This feels more like it to me. Trough retrogrades fully to the southwest with rainfall becoming much less widespread across the UK and temps becoming warm, then very warm.

The main thing that's changed is that there's no longer a peripheral low pressure development to the SE of the UK. As MWB noted earlier, this has been looking less of a given than the one to our southwest, based on ensemble guidance.

Question now is, can GFS sustain the retrograding trough theme? The models in general usually have a hard time doing that past about 6 days range - they have to overcome the inherent drift toward climatology.

[MikeC53]

Really dreadful output tonight especially for my area and further South/SW. 

[MikeC53]

Day 9 on the GFS and heavy rain almost everywhere.

[MATTWOLVES 3]

1 minute ago, MikeC53 said:

Really dreadful output tonight especially for my area and further South/SW. 

Misleading again mate.. Its delightful for the NW, and it's warming up... Yes its looking unsettled towards the SW but a lot can and will change with the movement of that Low.. I take it your from the South Midlands.. I don't think its a write off just yet.. The met have dry with sunny spells for the end of next week, and I'm only 40 or 50 miles North of you..

[northwestsnow]

 

GFS is really warm mid term with mid 20s quite widely...

Plenty of rain for parts of the SW especially as the trough spins away in the bay of Biscay.

Hopefully some big storms on the way too.

 

[Ben Sainsbury]

4 minutes ago, MikeC53 said:

Really dreadful output tonight especially for my area and further South/SW. 

Really isn't dreadful even for far S/SW , GFS precipitation charts will appear a lot worse than what it will actually be. ICON & UKMO both quite promising bar the Day 4-5 of a mixture of frontal rain and thunderstorms across Eastern parts. Temperatures at low-mid twenties, then an increasing improving picture as the week goes on. Bar the GFS of course, but its day 9 charts are useless.

Edited June 7, 2020 by Ben Sainsbury

[MikeC53]

1 minute ago, MATT said:

Misleading again mate.. Its delightful for the NW, and it's warming up... Yes its looking unsettled towards the SW but a lot can and will change with the movement of that Low.. I take it your from the South Midlands.. I don't think its a write off just yet.. The met have dry with sunny spells for the end of next week, and I'm only 40 or 50 miles North of you..

My area has seen dreadful summer flooding several times in the last 13 years and we are looking at that again if the GFS comes off. People are going on about storms but you won't have them if the low pressure centre is that close to us.

[Singularity]

The dive of the jet needs sharpening up here - with any luck this is just a typical NWP model shortcoming in evidence.

With the jet diving more gently like this, I'm not sure this run is going to manage the next step of trough retrogression... but we'll see.

Busy Sunday... I guess I'm doing all the posts I didn't do this past winter (there was hardly anything worth posting on!).

Edit: "Day 9 on the GFS and heavy rain almost everywhere" says MikeC53...

For one thing, those are showers that develop after a largely dry morning. For another, almost half the UK stays dry all day.

I'm all for right to free speech, but please don't abuse it like this.

Edited June 7, 2020 by Singularity