Model output discussion 14/04/18

[Summer Sun]

On 05/05/2018 at 23:33, Mike Poole said:

I've seen enough of the GFS 18z to feel confident that good times are coming, 

Sorry that won't enlarge, I've tried saving and uploading on the iPad but it doesn't work.  

It looks like this summer is going to be a classic, like we've not seen for a while, jet heading nicely north.  As much as we  can say this far out, what's  not to like?  GFS at T216 

4

Spot on so far

[Frosty.]

Really nice Ecm 12z ensemble mean tonight..this very long predominantly very warm / hot settled spell is about to strengthen even more and continue for most if not all of the next 10 days + across most of the uk..incredible spell..I don't want it to end and currently there's no real sign of it ending either!..hope that goes for the England team too!!

[MattStoke]

Am I going blind? BBC mention cooler air coming in from the north west early next week but I can’t see that on any of the computer models?

[Singularity]

 

If you're wondering what it is with ARPEGE, well for whatever reason, during settled weather it doesn't lower the temperatures enough overnight - just look at the examples above for the lowest temperatures shown early Saturday and then early Sunday! - and this in turn leads to temperatures becoming too high during the following day, which in turn leads to the following night being even more overdone, making the day after that even more so as well, and so on.

 

Longer-term, funny how the 12z GFS gets the idea of a trough digging down, but insists it must somehow gravitate toward the UK instead of staying where the Nino forcing would like it to.

The more west encouragement does reduce (but not to zero by any means) the probability of an Atlantic-Euro trough interaction leading to a short run of wetter conditions, but as pressure is forced to rise through NW Europe, it's possible that the low in place there later next week may still take an exit path that crosses at least the SE of the UK. Not as good from a watering perspective, but better than nothing.

[Frosty.]

5 minutes ago, MattStoke said:

Am I going blind? BBC mention cooler air coming in from the north west early next week but I can’t see that on any of the computer models?

The Gem doesn't agree with the BBC..

[Fourty Point Three Degrees]

24 minutes ago, MattStoke said:

Am I going blind? BBC mention cooler air coming in from the north west early next week but I can’t see that on any of the computer models?

Seriously its nothing to fret about. After a weekend of 30c a cool blast coming over the top of the HP would be welcome before the heat comes back mid week.  

 

(The BBC don't like hot weather so you can expect them to exaggerate and make things sound worse than it really is)

Edited July 4, 2018 by 38.5*C

[I remember Atlantic 252]

28 minutes ago, MattStoke said:

Am I going blind? BBC mention cooler air coming in from the north west early next week but I can’t see that on any of the computer models?

Saw that too Matthew, models do suggest it turning less hot early next week, a relief in a way though, still should be around 23 degrees

[cobby]

39 minutes ago, MattStoke said:

Am I going blind? BBC mention cooler air coming in from the north west early next week but I can’t see that on any of the computer models?

Does anyone take notice of BBC since the Met Office lost the contract?

[summer blizzard]

It will probably be diluted and is no doubt contributing to FI but the GFS is currently forecasting a whopper of a trade burst over the dateline.

[Mike Poole]

OK let's take a step back from trying to forecast in 10 days time whether this will breakdown or be prolonged.  GFS 18z at T120 certainly well in the reliable given the slow moving nature of the high:

When you see the jet this far north, like a giant tadpole with a wiggly tail, does it look realistic that there will be a breakdown soon?  No is what I think!

Edited July 4, 2018 by Mike Poole

[matty007]

4 hours ago, Mike Poole said:

OK let's take a step back from trying to forecast in 10 days time whether this will breakdown or be prolonged.  GFS 18z at T120 certainly well in the reliable given the slow moving nature of the high:

When you see the jet this far north, like a giant tadpole with a wiggly tail, does it look realistic that there will be a breakdown soon?  No is what I think!

Very true. With a jet that high it would take something very perculiar to change it. And it’s largely the way the jets been for a couple of months now, basically three. 

I can’t see a change happening anytime soon to be honest. This is the summer of high pressure, extremely dry and warm weather. Sometimes things just seem meant to be. Any breakdowns are quickly shunted aside. 

If you ask me, this is the best late spring/summer since 1976. Sure, we’ve had hotter spells but practically never anything of this longevity and stability. 

Edited July 5, 2018 by matty007

[mb018538]

Morning all,

Well if you like your settled weather, it's an ever improving picture from a couple of days ago. We are starting to see more support that despite the Azores high retreating slightly, forecasts are now showing the ridge to be stronger than the trough, and probably winning out. GEM this morning is a cracker, and nicely mirrors the extended ECM ensembles too:

Day 10 from last nights 12z:



Day 15:



Ridge holding strong for sure.

The dry weather has been extended a couple of days already on the GFS ensembles, and I'd expect these to dry up too as they get a better hold on things.



IF you dislike the heat it looks like next week is going to perhaps cool down a bit and become more comfortable too.....so the only bad news is no significant rain on the horizon still.

Edited July 5, 2018 by mb018538

[Djdazzle]

Not keen on the high position next week. Looks like eastern areas will be cool with a NNE drift. We just can’t seem to get the Azores HP to consistentl ridge in far enough.

[mb018538]

That above ppn chart should be 240 hours - still showing naff all in large parts of the UK anyway.



ECM is very pleasant, with the ridge holding rock solid, with 850s recovering through the week and into the weekend if anything:

[shaky]

Solid ecm this morning!!mid to high twenties all the way to the end!!high pressure holding fort at 216 hours!!no change this morning!!feels really humid out there aswell!!could maybe do with that annoying shortwave arcing around norway to move further east but thats about it!!heat set to continue!!

[Man With Beard]

ECM still going for a cooler couple of days mid next week (mid 20s). Apart from that, hot and settled all the way

[Frosty.]

Lovely Ecm 00z with both high pressure / strong ridging for the next 10 days + and generally very warm surface conditions across the uk, feeling hot in the strong July sunshine and there will be plenty of

[Guest]

Charts even start to look for the World Cup Final............did I really say that. In all honestly if it could be 30c until then and an England win it can rain everyday for the rest of summer. 

Looks as though once again high maxes (28-31c) will be achieved over a wide area from an airmass that isn't particularly warm (850s 9-12C generally) and derived from max solar input and super low soil moisture content. An easterly could once again become a pest for eastern areas next week with western areas having the highest temps and most sun. 

[Summer Sun]

No widespread rain for the next week at least just a few isolated showers

[johnholmes]

Nothing showing on the 500 mb anomaly charts that suggests any major change is imminent, 6-10 days nor really in the 8-14 period. The 8-14 NOAA does show a degree of Atlantic movement but it has done this over the past 2 weeks now and then. Here 16 days down the line another +25 C day so I suspect any marked change in the upper air pattern is still some way off

http://www.cpc.ncep.noaa.gov/products/predictions/610day/500mb.php

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

[mb018538]

1 hour ago, johnholmes said:

Nothing showing on the 500 mb anomaly charts that suggests any major change is imminent, 6-10 days nor really in the 8-14 period. The 8-14 NOAA does show a degree of Atlantic movement but it has done this over the past 2 weeks now and then. Here 16 days down the line another +25 C day so I suspect any marked change in the upper air pattern is still some way off

http://www.cpc.ncep.noaa.gov/products/predictions/610day/500mb.php

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

Indeed John, even the 8-14 day charts aren't much different:

http://www.cpc.ncep.noaa.gov/products/predictions/814day/500mb.php

[Djdazzle]

GFS 6z somehow manages to park a trough over the U.K. into FI. Very amusing to see how it does it.

[Frosty.]

One good thing about the Gfs 6z operational is most of the uk would get some welcome rain around mid July for the parched gardens and moorland where the fires are still raging..and of course for rivers / reservoirs, many areas haven't seen any rain as such for a long time..in the meantime, plenty of high pressure / strong ridging, sunshine and warm temperatures.

Edited July 5, 2018 by Frosty.

[bluearmy]

Extended eps clusters continue with one option. As has been mused already, one cluster tends to increase the uncertainty around the solution 

[Man With Beard]

11 minutes ago, bluearmy said:

Extended eps clusters continue with one option. As has been mused already, one cluster tends to increase the uncertainty around the solution 

and not even any clusters after T96. 

The uncertainty fits with the op runs recently - they look completely unconvincing to me - those weak heights look likely to be trampled over at any moment - but in the summer of 18 things just don't seem to work out as they normally do?