Model output discussion - hot spell beckons but then what?

[tinybill]

all i can  say is i hope people stay safe  there could be a few problems over  fri /sat

[knocker]

The North Atlantic surface analysis for midnight and the Camborne sounding and the 0300 WV image

With the low that has caused all of the recent problems well out of the way to the north east today a much better day with plenty of sunshine in many areas, and light winds so feeling quite pleasant. Showers will develop through the afternoon, mainly over Scotland but to a much lesser extent N. Ireland and northern England. But as can be seen on the Camborne sounding. a frontal surface and cloud around 500mb is the forerunner of the intense low to the south west and thickening cloud will encroach the south west with patchy rain arriving by mid afternoon.

Through this evening and overnight the main frontal system associated with the low will move up the country accompanied by bands of heavy and persistent rain and strengthening winds with only the north of Scotland escaping for the time being.

The band of heavy rain will continue to track north east through Friday clearing during the afternoon but heavy showers with hail and thunder in the mix will develop in the wake of the cold front and with the low now centred near Cork the winds will increase in the south to gale force. A marked regional temp contrast as well.

Over Friday night and through Saturday the low will track north east into the North Sea so a day of frequent heavy thundery showers on Saturday with strong winds in the south of the country gusting to gale force

The low continues to move away so the winds will abate on Sunday but with a couple of occlusions draped over the country a day of  sunshine and showers and turning a little cooler

By Monday the upper trough is negatively tilted over the UK so another cool day of sunshine and showers, with possibly thunder once more in the mix.

 

[knocker]

As can be seen the gfs still has the breakaway trough in mid Atlantic at T120

And by T144 it has merged with  our in situ trough and a deepening surface low is just west of Ireland and we are looking at the wet and very windy day on Wed if this is anywhere near the money

 

[knocker]

0615 from Eumetsat

The Airmass product is an RGB (Red, Green, Blue) composite based upon data from infrared and water vapour channels from the SEVIRI instrument. It is designed and tuned to monitor the distribution of different air masses and evolution of cyclones, in particular rapid cyclogenesis, jet streaks and PV (potential vorticity) anomalies. Due to the incorporation of the water vapour and ozone channels, its usage at highest satellite viewing angles is limited. The Airmass RGB is composed from data from a combination of the SEVIRI WV6.2, WV7.3, IR9.7 and IR10.8 channels.

[mb018538]

The 00z gfs runs spoils us with not one, not two, but three dartboard lows in the space of the next 10 days. Probably the worst summer run I’ve ever seen to be honest. Looks more like a bad October or November run than summer!

[Weather-history]

Similiar pattern to some past summer chart stinkers

End of July 1956, one of the worst summer days in the last 100 years in terms of rain and gales.

[knocker]

The ecm not deepening next weeks low as much as the gfs

[Frosty.]

Looking longer term there are hints of improvement in the GEFS 0z  with potential for summery weather towards the end of August.

[mb018538]

Not sure I've seen a 10 day UK ppn chart with a 200 on it before?



8 inches of rain in Scotland according to the GFS 00z. Thankfully it's an outlier and the ECM is nowhere near as bad!
 

 

 

 

 

 

Edited August 8, 2019 by mb018538

[knocker]

Nice cloud structure to the south west

[Methuselah]

Once again, the GEFS 006Z ensembles are not the best I've ever seen -- and largely meaningless after mid-month?

    

    

But at least we'll wake up to fresh early mornings; the humidity is getting tiresome, to say the least!

 

Edited August 8, 2019 by Ed Stone

[Summer Sun]

1 hour ago, mb018538 said:

Not sure I've seen a 10 day UK ppn chart with a 200 on it before?



8 inches of rain in Scotland according to the GFS 00z. Thankfully it's an outlier and the ECM is nowhere near as bad!

ECM takes near 200mm of rain down to Wales 

All academic of course at this range and will almost certainly change

[Man With Beard]

Even by the standards of recent Augusts, this has been a tiresome model watching period for those seeking something summery before the schools go back.

Right out to T360 on the clusters, we gave a negative anomaly to our NE which suggests a high tendency for low pressures to attack the UK right out to the end of the period.

Hopes of an improvement to more settled weather 30% at best. Best in the south, as is usually the case in such set-ups. Might favour sunny wind-facing coasts with downpours just inland, as was the case round here yesterday, 

[JeffC]

20 minutes ago, Summer Sun said:

ECM takes near 200mm of rain down to Wales 

All academic of course at this range and will almost certainly change

oh good, I only get about 175mm!!

[northwestsnow]

Looking at the 00z runs this is exactly the scenario i have had concerns about since May. 

August looks a lost cause -moreso further north west one heads, there must be flooding concerns for some areas over the next 10 days ..

Odds in an Indian summer ? If memory serves me right,poor Augusts tend to be followed by nice Septembers- 

I might be wrong here but i'm sure summer sun posted Glosea prediction for August a few months ago, and it looks nothing like the crud on offer, coupled with last winters amazing fail it just illustrates the pitfalls of Long range models.,even the best around- Glosea.

I will likely be back posting in Sept but as far as Summer is concerned, i'm taking a break as my posts will only  be a moan fest , thanks to all the members who have made it an enjoyable thread over the summer months..

Edited August 8, 2019 by northwestsnow

[Frosty.]

One thing I noticed about the latest models is the Ecm 0z doesn't look anything like as bad as the Gfs 0z operational regarding next week, the Gfs looked extreme with several vigorous atlantic depressions, by August standards. 

[knocker]

[chrisbell-nottheweatherman]

20 minutes ago, knocker said:

Like something we'd expect in November!  Classic deep Atlantic depression.

[mb018538]

1 hour ago, northwestsnow said:

Looking at the 00z runs this is exactly the scenario i have had concerns about since May. 

August looks a lost cause -moreso further north west one heads, there must be flooding concerns for some areas over the next 10 days ..

Odds in an Indian summer ? If memory serves me right,poor Augusts tend to be followed by nice Septembers- 

I might be wrong here but i'm sure summer sun posted Glosea prediction for August a few months ago, and it looks nothing like the crud on offer, coupled with last winters amazing fail it just illustrates the pitfalls of Long range models.,even the best around- Glosea.

I will likely be back posting in Sept but as far as Summer is concerned, i'm taking a break as my posts will only  be a moan fest , thanks to all the members who have made it an enjoyable thread over the summer months..

CFS went for a warm and dry August in the middle of July...it's going to end up the total opposite. How much more 'wrong' can you get than the exact opposite.
 

 

[chrisbell-nottheweatherman]

12 minutes ago, mb018538 said:

CFS went for a warm and dry August in the middle of July...it's going to end up the total opposite. How much more 'wrong' can you get than the exact opposite.
 

 

Makes me wonder why some members here seem to quote the CFS outputs as though they're going to be accurate.

[h2005__uk__]

How often are the 'FI' charts of the shorter-range models actually correct? I know they're supposed to be useful to pick up trends but it seems quite rare that 'FI' is correct. The same goes for the longer-range models like CFS.

If the success rate is too low then you could argue that 'FI' charts/long-range models may as well just pick solutions at random and be right some of the time...

[Methuselah]

Plenty of trough-ridge-trough oscillations on today's 06Z ensembles...?

   

   

And cool maxima look like being offset by warm minima? But, I guess that'd depend on timing?

[mountain shadow]

GFS 6z op was absolute Summer killer. Low after low spinning in with frequent Northerlies to boot.

Awful.

[JeffC]

1 minute ago, mountain shadow said:

GFS 6z op was absolute Summer killer. Low after low spinning in with frequent Northerlies to boot.

Awful.

I remember being on the top of Coniston Old Man on a rescue in August maybe 1987 or 88, windy as hell and blowing snow!!

[Polar Maritime]

Some high Cape values as the front moves N/E tomorrow, As shown on UKV.