Model output discussion - hot spell beckons but then what?

[Frosty.]

 

13 minutes ago, Djdazzle said:

I think favoured areas will do a lot better than 30!

Indeed, more like mid 30's c in the hottest spots further s / se

Anyway, here's the Ecm 12z operational so far..prepare to get hot under the collar and everywhere else!!!

Friday still looks very warm / hot across the far East / Southeast of England!

 

Edited July 20, 2019 by Jon Snow

[Snowy L]

All 3 models with good agreement on 850hpa temperatures on Thursday, 15c and 20c lines around Manchester and London respectively.

[thestixx]

10 minutes ago, northwestsnow said:

The heat reserved for the SE at 144 but still warm elsewhere -

EPIC EC det...

Very fine margins tho'!!

This would be a very welcome 'breakdown' for the weekend... Still pleasantly warm... How many fronts will be associated with that low though?

[northwestsnow]

7 minutes ago, thestixx said:

This would be a very welcome 'breakdown' for the weekend... Still pleasantly warm... How many fronts will be associated with that low though?

Good question stixx, if i'm honest i have no idea

The models converging on this low scooting up from the SW 120-144, key will be how far east the low gets in terms of the boundary between sweltering and less sweltering next thur/fri..

[Singularity]

30 minutes ago, Man With Beard said:

And the ECM at T120

Certainly the hottest of the three by Thursday. Though surprised how it got there after Wednesday's chart - the heat looked gone! 

35C or more likely on that but it's tight. 

This is painful watching! 

I think I might have sussed how it happens; the 'swing-in' low deepens faster than the other models have it doing in the early stages, while still in the western N. Atlantic, and this means that it starts to affect the path of the jet stream more, arcing it around more tightly. This has a slight amplifying effect on the planetary wave, slowing down the rate of eastward progression, and even appears to result in a slightly east of south flow across the UK for a time late Wed into Thu, that allows the main heat dome to edge northwest a little compared to noon Wednesday.

Something to watch out for in future runs is any sign of that low stretching south or southeast. That could set up a stronger flow from France on Thursday, potentially raising the peak England temp even higher than the 36-38*C that the ECM 12z + typical max temp error adjustment suggests. 

p.s. interesting that both FV3 and ECM almost set up another intense heat incursion around D9-D10. Also weird that both rapidly lift a low up from the south in a peculiar fashion - since when do lows move like that when there's little in the way of a trough to the north?

[Frosty.]

The Ecm 12z operational shows very warm continental air again edging up across the S / SE at day 9 and even day 10 the uppers look great but the weather looks very unsettled with probably heavy, thundery rain..think we will all hear the thunder and feel the warm rain but also bask in the hot sunshine during the week ahead, it looks plumey, hot and humid for a good few days next week..enjoy it while it lasts if you love heat.

Edited July 20, 2019 by Jon Snow

[MATTWOLVES 3]

The ECM  is becoming as erratic has the gfs for sticking a low pressure slap bang over us.. I've got a feeling this will look different come the mean. 

Edited July 20, 2019 by Mattwolves

[Cheshire Freeze]

5 minutes ago, Mattwolves said:

The ECM  is becoming as erratic has the gfs for sticking a low pressure slap bang over us.. I've got a feeling this will look different come the mean. 

Funnily enough it mirrors the GFS well- as Singularity has pointed out.

Edited July 20, 2019 by CreweCold

[Man With Beard]

@Singularity you called it right - ECM *raw* maximum of 36C in the SE corner on Thursday (so add a few more for the actual...?) - wow, a chart that hot at just T120. 

[Djdazzle]

3 minutes ago, Man With Beard said:

@Singularity you called it right - ECM *raw* maximum of 36C in the SE corner on Thursday (so add a few more for the actual...?) - wow, a chart that hot at just T120. 

36C raw, wow! If we could get a couple of westward corrections . . .

[MATTWOLVES 3]

9 minutes ago, CreweCold said:

Funnily enough it mirrors the GFS well- as Singularity has pointed out.

Like for like! It wasn't really supported by the mean though crewe. 

[Cheshire Freeze]

2 minutes ago, Mattwolves said:

Like for like! It wasn't really supported by the mean though crewe. 

The mean won't pick up on a microscale feature at day 10

[Downpour]

13 minutes ago, CreweCold said:

Funnily enough it mirrors the GFS well- as Singularity has pointed out.

That’s so far away in forecasting terms it’s hardly worth commenting on. ECM gives a breakdown of sorts on Friday but would still be a warm weekend for points SE (but 26c rather than 36c!)

[MATTWOLVES 3]

6 minutes ago, CreweCold said:

The mean won't pick up on a microscale feature at day 10

My mistake, I'm getting ahead of myself here, I forgot for a second we was at day 10...back to school matt you thicko.

[Cheshire Freeze]

Just now, Mattwolves said:

My mistake, I'm getting ahead of myself here, I forgot for a second we was at day 10...back to school matt you thicko.

Yes, won't happen as it's day 10 but I always find it interesting when two different models pick up on the same general pattern at that range. Especially with microscale features like we see above.

[Methuselah]

A forecast I just accessed, by an anonymous organisation that was once in association with Those Who Cannot Be Named, was suggesting that there's still a better-than-zero probability, of next week's very hot conditions lasting until next weekend...Shhhh!

Edited July 20, 2019 by Ed Stone
Lost marbles!

[MATTWOLVES 3]

How I envy you SEeners!! And easteners

Edited July 20, 2019 by Mattwolves

[Frosty.]

Looking at the longer term GEFS 12z into early August I would say more likely to be a north / south split but there are some nationwide anticyclonic members and even a few showing plume potential so hopefully more summery weather into the final month of this meteorological summer.

Edited July 20, 2019 by Jon Snow

[MATTWOLVES 3]

2 minutes ago, Jon Snow said:

Looking at the longer term GEFS 12z into early August I would say more likely to be a north / south split but there are some nationwide anticyclonic members and even a few showing plume potential so hopefully more summery weather into the final month of this meteorological summer.

I only hope the EC46 is wide of the mark for the far NW cause it shows one hell of a lot of rainfall... I no its not my backyard but I would hate to see what that model is serving up for them to happen. 

Edited July 20, 2019 by Mattwolves

[Gael_Force]

7 minutes ago, Mattwolves said:

I only hope the EC46 is wide of the mark for the far NW cause it shows on hell of a lot of rainfall... I no its not my backyard but I would hate to see what that model is serving up for them to happen. 

Where did you see that? The ECM 46 anomaly maps don't show anything too drastic from what I see.

https://www.met.hu/en/idojaras/elorejelzes/europai_elorejelzes/

[MATTWOLVES 3]

4 minutes ago, Gael_Force said:

Where did you see that? The ECM 46 anomaly maps don't show anything too drastic from what I see.

https://www.met.hu/en/idojaras/elorejelzes/europai_elorejelzes/

The precipitation charts I posted last night.... Which by the way I shouldn't have... Showed alot of rain towards the NW.. and only the far SE was really immune. I also mentioned September was showing as a drier and relatively warm month... They are accesable on weather.us but you need to be a member to view them. 

Edited July 20, 2019 by Mattwolves

[Man With Beard]

There's heavy support from the ECM ensembles for a very hot Wednesday, as one might expect, with about 75% of members either as hot or hotter than the op - also maybe half with the heat backed a bit further west. Certainly 35C or slightly higher starting to look a good call for that day. 

Individual ensembles not yet updated for Thursday/Friday but judging from the mean chart I'm guessing there's been a resurgence in the cluster that persists with heat into Friday - very interesting as these were the hottest runs of all when they appeared earlier this week. 

My assessment is that 38C, 39C or even 40C still cannot be ruled out, and now just at D4-D6. 

[Gael_Force]

5 minutes ago, Mattwolves said:

The precipitation charts I posted last night.... Which by the way I shouldn't have... Showed alot of rain towards the NW.. and only the far SE was really immune. I also mentioned September was showing as a drier and relatively warm month... 

I didn't see the charts you posted last night but the free sources of EC monthly data I have seen don't show anything overly excessive for rainfall.

[MATTWOLVES 3]

Here is the mean in all its glory. 

[Man With Beard]

(*see edit below *) 

Thursday's ECM ensembles - 60% of members are as hot or hotter than the op run (which itself threatened the 100F mark). About 20% are just behind, and the rest have cleared the heat away (which skews the mean). Again, a fair cluster has the extreme heat back as far as the Midlands. 

*EDIT* My apologies - this analysis was based on 1pm charts. On the 4pm charts, actually only a few get quite as hot as the op run - most of the 60% in the same "cluster" are close but a degree or two behind, even though they were level pegging with the op at 1pm

Edited July 20, 2019 by Man With Beard