Model output discussion - hot spell beckons but then what?

[Man With Beard]

ECM clusters return for the D11-D15 period, and once again the picture for the UK is a bit of a mess

Once again this rather odd combination that we've seen a lot of this season - a tendency to northern heights combined with an Atlantic trough that won't send a clear signal on whether it wants to push through into Europe or not. On all 4 clusters for T300, the strongest trough anomaly has dug in to our west/south west, putting us on the warmer side of the pattern, in spite of the northern blocking (better hope this doesn't happen in winter or there'll be anguish on this forum). On clusters 1 and 4, it looks like the changeable weather has spread across the UK into Scandi, but clusters 2 and 3 maintain reasonable heights over mainland Europe and may hinder the progress of the trough over all or parts of the UK. Such is the position that you could imagine a plume squeezing up the west side of Europe again. 

So D11-D15, changeable at times, even unsettled to the NW, but warm at times too - could be a good shout? 

 

[MATTWOLVES 3]

I said the other day that if we can get low pressure to sit in a favourable position, we could again be tapping into some continental heat... The icon shows this possibility at day 7.One thing for sure it looks like a warm week... The low pressure to the SW perhaps bringing some thundery showers to more W/SW areas by next weekend... All along way off though. 

[Tim Bland]

2 hours ago, Onding said:

Take at mean value, yes. However, I think @Ed Stone was referring to the increased amount of FI scatter compared to recent GEFS. In which case I agree - it is uncertain later on - perhaps some emerging trends to come?

I’m not talking bout the mean I’m talking about the whole ensemble set. If every run shows average conditions, then there’s a fair chance it will be average! There isn’t much scatter in the ensembles & there is not 1 ensemble member showing heat and only a couple that are much below average? They could all be wrong I suppose ....

Edited July 28, 2019 by Tim Bland

[knocker]

[northwestsnow]

33 minutes ago, knocker said:

Its already quite bad round these parts - reports of flooding in Greater Manchester ! GFS looks primed to bring lots of rain next week too.

On closer inspection its also quite warm next week with most days 20-23 degrees across much of the country - i wonder if there is thundery potential..

Edited July 28, 2019 by northwestsnow

[Methuselah]

Here at T+315, things have the potential to go downhill quickly...I hope they don't!

   

[knocker]

35 minutes ago, northwestsnow said:

Its already quite bad round these parts - reports of flooding in Greater Manchester ! GFS looks primed to bring lots of rain next week too.

On closer inspection its also quite warm next week with most days 20-23 degrees across much of the country - i wonder if there is thundery potential..

I think that is the point nws as the thundery low moves across the country

Edited July 28, 2019 by knocker

[knocker]

The gfs 5-10 anomaly no big surprise with the TPV to the north east and the high cell over Iceland resulting a hugely inert north east Atlantic and a very slack pattern over the UK. Not a lot going on, perhaps some thundery stuff creeping up from the lower pressure in the south with temps varying around the average

Edited July 28, 2019 by knocker

[Frosty.]

I'm certainly not giving up on the idea of another plume or two during august and there are still a few hints here and there but honestly, what I'm looking for is summery charts whether it's high pressure, ridging or plumes..like most on here I remain hopeful that there's more great weather to come although the GEFS 12z is, putting it mildly... mixed.

 

[I remember Atlantic 252]

1 hour ago, Ed Stone said:

Here at T+315, things have the potential to go downhill quickly...I hope they don't!

   

proper FI ed, looks decent that surely, 25 degrees I'd have thought

[Methuselah]

17 minutes ago, Jon Snow said:

I'm certainly not giving up on the idea of another plume or two during august and there are still a few hints here and there but honestly, what I'm looking for is summery charts whether it's high pressure, ridging or plumes..like most on here I remain hopeful that there's more great weather to come although the GEFS 12z is, putting it mildly... mixed.

 

Aye, Karl: never rule anything out, on the grounds that the GEFS doesn't show it!

   

   

[East_England_Stormchaser91]

Certainly some more interesting weather for Tuesday coming up. Thunder looks likely in quite a few places. 

FI is showing quite an elongated northerly coming in, but not really affecting temperatures too much.. 24-25c still further south on many days! Once again, this is draining the arctic from cold, and we see yet again, some very warm conditions up there.. not good for the already record level lows of ice. 2012 at this rate is definitely going to be beaten, unless we see some radical change, readjustment of patterns and a big cool down. Implications on this winter will be interesting this year. 

[Singularity]

On 27/07/2019 at 16:25, Tamara said:

At the moment, the modelling is best 'seeing' the phasing of falling of pressure across Scandinavia (from its latest downstream ridge peak) with the  trough(s) approaching in the Atlantic next week. The caution is in extrapolating and making assumptions too far ahead from this - and so not a bad thing to be mindful of the risk of NWP persisting, in error, of this synoptic stage for too long.

Too soon to suspect  August may follow any alleged underwhelming tradition, even if the ending of July and heading into the new month might appear to be getting off us off to a (relatively) unremarkable start. But temperatures still look respectable over the coming period and perspective has to be set against the spectacular events of last week

Worth reiterating the final two paragraphs from Tamara's very insightful update yesterday afternoon.

The state of the EPS clusters is arguably reflective of the models being automatically inclined toward moving the trough through the UK via a flat jet pattern, but starting to pick up on what may prove, yet again, to be the (at least main) trough actually staying west of the UK.

Studying plots of wind and velocity potential anomalies, I observe the Nino standing wave to still be present, and GEFS showing a tendency to attack it with TWBs, but with this being nothing new in recent weeks; the model keeps trying to take the standing wave apart, but this keeps proving to be a red herring. Observing the FV3 runs of the past few days, it appears that this model has inherited most or all of that bias.

To be fair, ECM/EPS show a similar bias, just not as persistent - that model had a major mishap with late June but fared better in early-mid July.

 

IMO, August has a good shot at delivering a longer run of very warm or hot weather than July managed. Naturally, odds are it doesn't reach such extremes as what we saw last week, but given all the 'thermal momentum' in the European vicinity (in the form of SSTs and ground temps), there will need to be a good amount of rain across mainland Europe to fully close the door on another extreme heat event manifesting, should high pressure build as it looks capable of doing at some point within the first half of August.

2nd half of August, it becomes more a case of extremes relative to the norm for the time of year, rather than all-time. Too far out to envision how the standing wave might be faring at that time, but as yet, there aren't any clear signs of, for example, MJO activity capable of delivering a 'fatal' blow.

One more month until we begin what I believe could be one of the weirdest, wackiest autumns on record considering the extraordinary amount of anomalous warmth amassed at the high latitudes, most significantly in the Arctic Ocean.

[MATTWOLVES 3]

The ECM looks rather stagnant in its patterns.. We have heights to the North, heights to the SW.. A low pressure to the West... I would imagine warm sunny spells and an ongoing risk of heavy thundery downpours.. Temps remain warm, and perhaps even more so later... That's my take on it. 

Edited July 28, 2019 by Mattwolves

[mb018538]

Just looks pretty mundane and boring right out through the first 7-10 days of August. Sunshine, showers, temperatures around average. -ve nao, negative tilt in the Atlantic and suppressed Azores high. No signs of any settled weather or heat on any of the ensembles. Probably leaves us 2-3 weeks of summer for one last hurrah.

[Frosty.]

Tonight's Ecm 12z ensemble mean isn't so bad, I think most of the rain that falls will be in the form of showers, many of them heavy and thundery with sunny spells between, however, as well as showery troughs there is some ridging indicated too so at least some fine weather at times. Temperatures generally close to average, humidity levels much lower than last week so feeling fresher but it's not a disaster and certainly doesn't mean we have seen the last of the truly summery weather...I'm sure August will deliver at some point!! 

[knocker]

Little to add to earlier comments vis the EPS anomalies and NOAA except to reiterate that the ext period is still looking more fluid/changeable with temps varying around the average

 

[knocker]

Not unexpectedly some significant differences with max temps in parts of the country not under the cooling umbrella of frontal rain

http://www.met.reading.ac.uk/~brugge/18.html

[MATTWOLVES 3]

The next 7 days looking like a bit of everything, sunny spells, showers, but rather warm with it... No point in getting to hung up over it, as the models struggle beyond a week! Plenty of time for another plume or 2...just to refresh your memories a little... 1906 heatwave stemmed from August 31 to the 3rd of September... The temperatures went above 32c for 4 consecutive days. The highest temp being recorded at 35.6c in Bawtry,Yorkshire. And Gordon Castle in Scotland reached 32.2c. And let's not forget 2016...August the 24th when 33.8c was recorded in Suffolk. This was bettered further on September 13th 2016 when 34.4c was recorded in Gravesend. So I think there is still plenty of time for us to achieve another hot spell or 2, especially as we have some serious heat in parts of Europe still.. Not to mention a fair bit of heat over the Arctic regions, could be a very interesting Autumn for sure. 

[knocker]

The interesting intense little low at 0600 UTC. Ac is already encroaching here Apologies if this  is off topic

Edited July 29, 2019 by knocker

[Captain Shortwave]

Make the most of today which should be a decent day, some lively weather to come with heavy (perhaps thundery) showers for the rest of the week. One thing to note that even when pressure rises, it is a weak affair do showers could still be present along with the risk of mist/low cloud for eastern coasts if the predicted NE wind sets in.

need to watch for an early taste of autumn later on with an Atlantic ridge/Scandinavia  trough setting up which could deliver a rather cool northerly. Still a long way off and the blocking could behave very differently.

[thestixx]

9 minutes ago, Captain Shortwave said:

Make the most of today which should be a decent day, some lively weather to come with heavy (perhaps thundery) showers for the rest of the week. One thing to note that even when pressure rises, it is a weak affair do showers could still be present along with the risk of mist/low cloud for eastern coasts if the predicted NE wind sets in.

need to watch for an early taste of autumn later on with an Atlantic ridge/Scandinavia  trough setting up which could deliver a rather cool northerly. Still a long way off and the blocking could behave very differently.

Joe Basta rdi was suggesting the cool pool over Russia would be sufficient to cause another potential plume event here with another trough over the Atlantic... Although the price we're now paying for that last event is thoroughly depressing.

[Polar Maritime]

UKV take on rainfall from the little Low spinning up from the S/W later today and into tomorrow, A fair bit of rain could fall in places that have already had big total's over the weekend.

 

Edited July 29, 2019 by Polar Maritime

[johnholmes]

8 minutes ago, Polar Maritime said:

UKV take on rainfall from the little Low spinning up from the S/W later today and into tomorrow, A fair bit of rain could fall in places that have already had big total's over the weekend.

 

True PM, but saves me needing to water before I go away until Friday!

Nor do the anomaly charts really suggest another sunny and hot spell being imminent

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

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

Edited July 29, 2019 by johnholmes

[I remember Atlantic 252]

Aye, was thinking Wed non stop washout here, wrap around days is wettest setup here, timed for day as well