Model output discussion 14/04/18

[Singularity]

 

No surprises here; ECM ensembles more keen on keeping the MJO in an active, propagating state, which does lend itself to the better retention of HP across the UK in the 8-10 day period - albeit only weakly so.

Longer-term, we need the ensembles venturing into phases 6-7 to be sniffing out the right trend, as this will set up the forcing needed to help keep HP where we'd like it during mid-late June and beyond.

We continue to straddle the line between 2006 and 2007 in terms of similarities to the overall state of climatic forcing. The difference between a fantastic summer and a tragic one! 

[Frosty.]

Hope you guys in the south had fun with those severe thunderstorms last night

Liking the latest models, especially the Ecm 00z which shows further very warm summery weather to come with more storms for the south but plenty of dry and sunny spells too.

Edited May 27, 2018 by Frosty.

[Frosty.]

Very good Gfs 6z operational which is pretty much dominated by high pressure / ridging throughout the run.

[Frosty.]

40 minutes ago, Frosty. said:

Very good Gfs 6z operational which is pretty much dominated by high pressure / ridging throughout the run.

Ditto the GEFS 6z mean..looking very good..in my opinion.

[Man With Beard]

EC clusters starting to come together post next weekend. Looking settled, and probably reasonably comfortable for temperatures, as a gentle north westerly flow in June can still be quite warm. Not out of the question that the surface flow will remain continental in the south. No genuine attempt at a Greenland High here. 

[matty007]

That N’rly wind is so irritating. Without it it would feel truly very warm. 

With a S’rly wind, you’d expect low to mid 30’s I reckon. 

 

 

[Singularity]

2 hours ago, Man With Beard said:

EC clusters starting to come together post next weekend. Looking settled, and probably reasonably comfortable for temperatures, as a gentle north westerly flow in June can still be quite warm. Not out of the question that the surface flow will remain continental in the south. No genuine attempt at a Greenland High here. 

Signs of very warm tropical maritime air circulating around the high next weekend. Cloud cover will be the only thing standing in the way of high 20s temps in SE or CS England if that happens (former if NW wind, latter if N or NE wind). Some of my highest maximums have occurred with a N wind.

The way those ridges keep drifting back east after only a small venture west does bring to mind some of the legendary summers of past; it's the prime way to achieve an unusually dry summer with frequent warm to very warm, sometimes hot spells of weather. The ridges are perhaps a bit further north than usual on this occasion though. Indeed I wonder if the low Arctic sea ice is altering the pattern in favour of higher heights over Scandinavia than we'd otherwise be seeing.

The MJO versus residual La Nina battle really is the critical factor this year as to whether we see the gently swaying ridge pattern persist for much of the summer or not. Though even if we do see things pan out in favour of persistence, some changes will inevitably occur, as weaker La Nina forcing reduces the strength of the subtropical ridge - but this can open the door to ridges sitting right across or just E/SE of the UK for longer periods without being challenged much.

[cheese]

1 hour ago, matty007 said:

That N’rly wind is so irritating. Without it it would feel truly very warm. 

With a S’rly wind, you’d expect low to mid 30’s I reckon. 

 

 

Feels nice to me. A pleasant breeze on a warm summer's day is always appreciated.

[Djdazzle]

2 hours ago, matty007 said:

That N’rly wind is so irritating. Without it it would feel truly very warm. 

With a S’rly wind, you’d expect low to mid 30’s I reckon. 

 

 

Low to mid 30s? The uppers are nowhere near high enough to get those temps, whatever the wind direction.

It’s hard enough to get those temps in high summer, let alone late spring.

[mb018538]

9 minutes ago, Djdazzle said:

Low to mid 30s? The uppers are nowhere near high enough to get those temps, whatever the wind direction.

It’s hard enough to get those temps in high summer, let alone late spring.

Quite true....we’re gettinng about the maximum you’d expect from the uppers. 80f+ in May is still good going, maybe we’ve been spoiled this year!

[northwestsnow]

Another marvellous GFS this evening, UKMO at 144 however throws a bit of a wobbler with the trough moving down - hopefully a blip.

[Man With Beard]

Yes, the GFS maintains and actually strengthens the high to the north. It just instinctively looks hot for the first five days of June, mid to high twenties I'd have thought, and the continental draw will surely mean 30C coming into play regularly if it carries on. Thunderstorms remaining a risk but again not the type to wash out the cold. 

UKMO would be sod's law. 

[Mike Poole]

Output looking good tonight, here's the GFS 12z:

At T192 the jet:

It can go there as much as it likes !

And in the land of fantasy, Narnia and unicorns, here at the end of run:

Go the red!

Edited May 27, 2018 by Mike Poole

[northwestsnow]

There is no doubting Gfs is great for summer lovers.. the 850s on ukmo show warm weather persisting until next weekend altho the trough is already introducing cooler north Atlantic air into the far northwest at 144hrs... 

Nervous wait for ECM .. although im probably being greedy .

[Mike Poole]

GEM 12z here to T240:

Although at the very end the high does head In the Greenland direction, there's still high pressure across into Scandi, OK with this run. I'd like to highlight the jet stream, here on this run at T180:

Compare with my comments on the GFS run ^ in my experience in the past when the jet has gone well north it's been weak  but at the moment it really looks like it's got the bit between its teeth.  If it keeps it's teeth clean  then all's good.

Edit, and the GEFS ensemble mean at T264 supporting a UK high, roll on summer '18 it is your time, 

Edited May 27, 2018 by Mike Poole

[Frosty.]

4 hours ago, Frosty. said:

Ditto the GEFS 6z mean..looking very good..in my opinion.

Ditto the GEFS 12z mean..the summery pattern does look like extending well into early june, perhaps nearer to mid june!..hope it goes on and on..and on!

[Frosty.]

The good news from the Ecm 12z is there is more of the same very warm weather to look forward to during the week ahead with plenty of sunshine but also more thunderstorms breaking out, mainly across southern uk and temps generally into the mid 20's celsius range..and high 20's c at times for the most favoured spots further s / se..pressure becomes higher from the west towards next weekend so becoming generally dry and fine as high pressure builds / ridges in from the atlantic but staying generally warm / very warm.

Edited May 27, 2018 by Frosty.

[Mike Poole]

ECM 12z, picking  up the story at T168:

How quickly is this high going to make it over the UK with no jet to drive it?

 next frame, T192:

Steady small steps, (I'm commenting on this as it comes out, await the T216!)

Didn't I see this somewhere before this evening?  ECM T240:

Edited May 27, 2018 by Mike Poole

[Singularity]

ECM has UKMO's upper low across the UK at +144, but it's so weak that it only serves to trigger heavy downpours / thunderstorms rather than it bringing a spell of persistent rain.

Enough sun still gets through to lift temps widely into the low-mid-20s.

Every chance that low will end up staying to the west anyway as per GFS; for some mysterious reason, the models on our side of the pond have been underestimating the Scandinavian ridging time and time again in recent months. It wasn't that way in times past; GFS has the long record of Scandinavian mishaps - but the game seems to have changed drastically!

The way the ridge keeps on coming back in the GFS 12z run is something to behold.

[ANYWEATHER]

Evening All....A very thundery outlook for the week ahead , more picticularly southern Britain, in the more reliable time frame , but warmth and humidity look high on the Uks weather priority in the days ahead. No point looking at weather forecasts for rainfall and thunderstorms , ,just keep checking out Netweathers rainfall radar....Its a Nowcast situation..

[northwestsnow]

If we discount the ukmo 144 chart then the warm spell looks good to go for another 7 days minimum.

I wonder if the massive strat warming event in Feb really has thrown the atmosphere into chaos,probably one for the experts but the UK weather since late Feb has been more continental then maritime , i'm loving it

[Man With Beard]

Yep, like the rest of you I see the ECM as pretty much a repeat of the current situation start to finish. 

Is any one else viewing these charts with a sense of disbelief? Just what the monkeys has happened to the Atlantic? When will it come back? Is it ever coming back? 

This also feels like the beast from the east but in reverse. In winter, we were looking for injections of cold from the north east to get deep cold in. Now, we're looking for injections of warmth from the south into the pattern to get deep heat in. I know I've said it a few times recently but I'll say it again because it sounds exciting for heat lovers - I don't think we are that far away from such a scenario, and it will take a much smaller model shift to bring genuine heat into things than it will to get rid of the pattern. Bearing in mind, we are now at a stage where the continent can generate its own heat so long as Atlantic / Arctic influences stay away. 

Edited May 27, 2018 by Man With Beard

[matty007]

4 hours ago, Djdazzle said:

Low to mid 30s? The uppers are nowhere near high enough to get those temps, whatever the wind direction.

It’s hard enough to get those temps in high summer, let alone late spring.

On the contrary, 30c has occurred a few times in Late May. The sun is very strong and the atmosphere warms very quickly. 

Don’t get me wrong, this is lovely weather and a welcome change to the usual dross this time of year. But I like it as warm as possible, I like extremes, so that N’rly was a real pain to me. You could feel the sun was very very powerful today and could feel the real warmth behind the northerly wind. 

If we had a southerly gentle wind today it would have definitely been bordering on 30c. The N’rly dimmed the heat by at least 5c

[matty007]

31 minutes ago, Man With Beard said:

Yep, like the rest of you I see the ECM as pretty much a repeat of the current situation start to finish. 

Is any one else viewing these charts with a sense of disbelief? Just what the monkeys has happened to the Atlantic? When will it come back? Is it ever coming back? 

This also feels like the beast from the east but in reverse. In winter, we were looking for injections of cold from the north east to get deep cold in. Now, we're looking for injections of warmth from the south into the pattern to get deep heat in. I know I've said it a few times recently but I'll say it again because it sounds exciting for heat lovers - I don't think we are that far away from such a scenario, and it will take a much smaller model shift to bring genuine heat into things than it will to get rid of the pattern. Bearing in mind, we are now at a stage where the continent can generate its own heat so long as Atlantic / Arctic influences stay away. 

Amen to that. 

Im praying it continues as long as possible and would love a repeat of June 76’, And also July 2006. 

The ingredients are certainly there. Just need the warmth to build and the Atlantic at bay 

[Frosty.]

Well another great week coming up, another very warm BH Monday too!...a continental pattern with sunshine, high temps and then thunderstorms breaking out. Further ahead tonight's Ecm 12z ensemble mean shows the summery weather extending well into early June..long may it continue, the longer the atlantic stays benign the better our summer prospects will become!