Model Output Discussion - 1st June 2015 12z--------->

[summer blizzard]

GEM and GFS more or less have a northerly by day 9, Euro is on its own..

 

Edited June 6, 2015 by summer blizzard

[Polar Maritime]

Yes the slack Northerly is shown again by the GFS this morning for around the 12/13th. ECMWF only has it as a weak affair touching Scotland..  Cornish Pasty ?

 

Edited June 6, 2015 by Polar Maritime

[MR EXTREMES]

GEM and GFS more or less have a northerly by day 9, Euro is on its own..

 

Let's not forget that northerly flows that end up futher East into Scandinavia are very common indeed.

And that the likelihood of a none northerly runner could well be a realistic outcome.

Even so if the northerly happens blink and it's gone only to be replaced but a renewal of high pressure.

As was the situation yesterday with heat and humidity.

Might be worth checking back the previous weeks charts as I can see it the heat and humidity at one stage looked more prolonged and robust but in reality it was a blink and over moment.

I'm still confident that June is starting to filter out the little blips of polar air source soon to be replaced but a more average but settled high pressure as this coming week progress.

Eventually leading to more sustained and favourable height position to draw in some heat.

Or maybe some homegrown heat.

certainly not a wash out by far and always found that el nino,

although not over all driver does deliver a nice summer.

[knocker]

Looking at this morning's anomalies, although not total agreement vis the trough, there would appear to be movement to a general agreement on the upper pattern.

 

HP Greenland, mid Atlantic and eastern Europe, LP Pole, Spain with trough in between. So the likely surface analysis (broad brush) is low pressure from the Pole south to the Med with HP to the east and west. How the detail will emerge from this is not yet obvious.

http://www.tropicaltidbits.com/

Edited June 6, 2015 by knocker

[Frosty.]

I noticed the Gfs 00z showed snow on high ground in Scotland on the 14th, the 6z doesn't but it still shows unseasonably cold Northerly winds with -5 T850 hPA flooding south into northern scotland. What the hell happened to the summery charts..lol

Edited June 6, 2015 by Frosty.

[knocker]

It's still as well to remember it's still a bit up in the air, it's a transitory period, and there is a fair difference between the last two GFS runs.

Courtesy weatherbell.

 

[seaside 60]

I noticed the Gfs 00z showed snow on high ground in Scotland on the 14th, the 6z doesn't but it still shows unseasonably cold Northerly winds with -5 T850 hPA flooding south into northern scotland. What the hell happened to the summery charts..lol

The same as all those lovely cold charts you posted in the winter, lol...

To be honest I got the impression that late spring and early summer was always going to be average to below average, so these cool trends in the models dont surprise me at all.

[coldcomfort]

For the 6th day in a row these 10 day anom charts show mean temps across the UK (and indeed the northern half of Europe) to be several degrees below average. OK given the fact the next 5 or 6 days should be largely dry it will feel pleasant in the sunshine, but with more cloud and the likelihood of rain from Friday it's going to start feeling decidedly unpleasant imo - not really what we want to see at all as we close in on mid summers day.   http://wxmaps.org/pix/temp4.html

Edited June 6, 2015 by coldcomfort

[knocker]

By several I take it you mean average to -2C for the UK?

Edited June 6, 2015 by knocker

[Summer Sun]

10 day 2m temp anomalies show quite a bit of northern Europe seeing below normal temps

 

Edited June 6, 2015 by Summer Sun

[coldcomfort]

By several I take it you mean average to -2C for the UK?

1-4c below average as a mean according to those charts I posted, 2-3c below average according to those just posted by SS.

Edited June 6, 2015 by coldcomfort

[mushymanrob]

Looking at this morning's anomalies, although not total agreement vis the trough, there would appear to be movement to a general agreement on the upper pattern.

 

HP Greenland, mid Atlantic and eastern Europe, LP Pole, Spain with trough in between. So the likely surface analysis (broad brush) is low pressure from the Pole south to the Med with HP to the east and west. How the detail will emerge from this is not yet obvious.

http://www.tropicaltidbits.com/

 

not a sustainable pattern id have thought, so whilst it might well happen, imho it wouldnt last long.

not that what might replace it will be better... thats open for debate.

 

By several I take it you mean average to -2C for the UK?

 

lol.. indeed... im not worried about temps on the lower side of average, as ive mentioned several times before, itll feel very nice in the sun.

hmm.... not liking the 06z so much, the threat of an unsettled northwesterly isnt as 'good' as previous runs, so lets hope its just wrong and not picking up on a new pattern.

1-4c below average as a mean according to those charts I posted, 2-3c below average according to those just posted by SS.

 

but 4c below average in strong sun feels better then average under cloud....

[weatherguru14]

You think its warm today?? the wind  makes it feel cold.. if its stop blowing for a  second you can get a tan.. All you get with this wind is a frostbite.. Am all for putting a  positive slant on it. But I call summer has warm. 15c  is warm when  the wind doesn't blow. It feel about 9c in the wind..Looking at the weather charts. Am with cold comfort. whos honest with his posts.These are not summer charts.. They maybe summer charts for the UK. because that's how the weather is,in these isles. But for  summer weather  or decent warmth.. so far the first week of summer has been poor temperature wise..

Am all for a positive outlook. But the way its going June will be colder than Aprill..that's after people  saying  its going to be a flaming June..Cold comfort is right in  their assessment.. The weather charts look on cold side.

[knocker]

1-4c below average as a mean according to those charts I posted, 2-3c below average according to those just posted by SS.

 

I'm afraid I don't understand what you mean by "1-4c below average as a mean". Your post links to one anomaly chart which as far as I can see shows two anomalies over the UK. Part of the UK is zero and the rest 0--2C. Not that any of this matters a jot.

[Tamara]

Current modelling continues to reflect further downward tendency in Atmospheric Angular Momentum with the Global Wind Oscillation soon returning to Phase 1/2 and inviting the more westward positioning of High pressure from the weekend onwards - much as stated seemed likely in my last couple of posts

 

http://www.atmos.albany.edu/student/nschiral/research/gwo/gfsgwo_1.png.

 

A sure sign of this further drop in AAM comes from the MJO forecasts, and the recent shift of consensus emphasis for tropical convection to head back through towards the Indian Ocean in Phase 3. In this respect the ECM forecasts have taken the first prize over other models in recent uncertainty.

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/ECMF_phase_51m_full.gif

 

It is this evolution that seems likely to allow the High pressure to recede westwards just enough beyond the 7 day period to allow rather more unsettled conditions to, probably briefly, interrupt the fine weather.

 

However, with the upper vortex finally removed from Canada,. there is virtually no chance of a return to the unseasonal conditions seen recently and a much more typical summer-style slack drop of heights would seem likely the case over the UK and North Western Europe

 

More about that possibility as times moves on though

 

For those looking for real heat, it remains a waiting game for Angular Momentum tendency to rise once more. To repeat the same mantra as before - a low tendency state will always inhibit pressure building further eastwards across the UK and will keep inviting cooler air to stay closer to our north than many would prefer at this stage in early summer.

 

Illustration of this is how those higher uppers suggested in the modelling have been eaten away bit by bit over the last couple of days as tropical (MJO) and extra tropical (GWO) signals have become more certain 

 

All in all though, there is nothing to complain about at all for the weekend and much of next week - with some very pleasant quiet weather to look forward to after a thundery day in southern and eastern parts on Friday

 

Previous post carried for to assess developments

 

In many respects there is little to add to UK prospects in terms of detail.  With strong convection becoming set in place over the Indian Ocean, Atmospheric and Angular Momentum is sent tumbling from higher tendency Global Wind Oscillation Phases 3/4 back towards Phase 1 and then suggestions of a stronger amplitude Phase 2 - to reflect the intensity of the Indian Ocean convection signal.

 

http://www.atmos.albany.edu/student/nschiral/research/gwo/gfsgwo_1.png

 

This ECM forecast link is taken from WSI site to give a profile indication of the depth and possible longevity of this Indian Ocean convective signal

 

https://pbs.twimg.com/media/CGv9yq6UYAAYfGz.png

 

Mirroring this graphic convective representation, ECM MJO Phase forecast high amplitude progression through Indian Ocean MJO Phase 2 into 3 - before eventual death spiral and indeterminate forcing on the overall pattern

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/ECMF_phase_51m_small.gif

 

GEFS predictions suggest that the Indian Ocean signal is a little less shorter duration, being linked to intra seasonal kelvin wave suppression

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/NCPE_phase_21m_small.gif

 

Notwithstanding the current model disagreement over MJO Indian Ocean convective strength and duration, the synoptic knock-on response in the closer 10 day period is the correct one in line with the upstream tropical forcing and associated drop in AAM.

 

A negative trend down in the PNA index

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/pna.sprd2.gif

 

This weakens the sub tropical jet over the Pacific, and in the process retrogresses US west coast heights, increases sub tropical ridging across SE USA and retrogresses our downstream strong Azores/Atlantic ridge High westwards in the process.

 

http://www.nc-climate.ncsu.edu/secc_edu/images/Negative_PNA.jpg

 

Pressure weakens over UK and Europe in the void left where the ridging was residing - with a main upper trough over Scandinavia, consistent with GWO Phase 1. Compliant with earlier analysis, cool air is thus replenished to the north, but with stratospheric summer now prevailing, a much reduced seasonal jet pattern in place to what has been seen. Warm and humid air is set to remain ever present to our south

 

Its common for the UK to be the indeterminate zone - especially with such contrasting airmasses north and south of us. Such air mass contrasts provide the easy answer as to why the GFS persists with making more of the thundery low development on the nearby continent after midweek this coming week.

 

Its a case of seeing exactly how the indeterminate void is filled over the UK in terms of slacker lower pressure once the High weaken and recedes westwards later this week. The Euro's currently make less of this continental shallow feature and thus the decreasing temperature profiles as we head south to north are less clearly delineated than the GFS is currently modelling

 

Longer term evolution is as expected also rather uncertain - but with the background pattern as it is set over the next 10 to 15 days, then no real heat-wave seems likely at the moment in this period - although southern and eastern parts closest to the continental warmth might tap into this from time to time.

 

Cool air to the north, under upcoming low AAM regime, in tandem with summer seasonal jet profile heading north suggests that high pressure ridging will continue to ebb and flow, between troughing in the outlook period. Its a case of sitting out and watching the events upstream for further sustained high pressure development (beyond the next 5 days High pressure), but there should be some further pleasant weather amidst a rather changeable and mixed pattern.

 

Anyway, in the meantime, plenty of fine weather to enjoy whilst the high sits close to us till later next week - and complications arrive from both the north and the nearby continent

Edited June 6, 2015 by Tamara

[knocker]

not a sustainable pattern id have thought, so whilst it might well happen, imho it wouldnt last long.

not that what might replace it will be better... thats open for debate.

 

 

 

The trough is quite transitory and HP from the SW is the order of the day with both the GFS and ECM in the ext.. Much on the lines of this. But of course that's way down the line but would be consistent with the EC32.

[Frosty.]

The GEFS 6z mean shows an increasingly warm and settled outlook beyond the cooler less settled blip at the end of next week, the Azores high builds in strongly for the mid June period which could set us up for a good second half of the month. In the meantime, the short term looks decent with high pressure bringing strong sunshine during the week ahead but it will turn more unsettled across the northwest corner of the UK after Tuesday. It's a very encouraging mean longer term

[mushymanrob]

You think its warm today?? the wind  makes it feel cold.. if its stop blowing for a  second you can get a tan.. All you get with this wind is a frostbite.. Am all for putting a  positive slant on it. But I call summer has warm. 15c  is warm when  the wind doesn't blow. It feel about 9c in the wind..Looking at the weather charts. Am with cold comfort. whos honest with his posts.These are not summer charts.. They maybe summer charts for the UK. because that's how the weather is,in these isles. But for  summer weather  or decent warmth.. so far the first week of summer has been poor temperature wise..

Am all for a positive outlook. But the way its going June will be colder than Aprill..that's after people  saying  its going to be a flaming June..Cold comfort is right in  their assessment.. The weather charts look on cold side.

 

yes its certainly warm, in or out of the wind, and the wind doesnt prevent tanning. frostbite? lol...

[Nouska]

 That is an interesting GWO forecast chart, really tanking if correct. I had a look through the archives on the site to look at other strong Nino years - only two in the archive period but very different to the present time.

 

We are similar to and forecast to track the '97 event but have a look at the AAM for '97 as compared to the present time.

 

   

 

Is it this divergence that is causing all the NWP changes - new algorithms needed!

http://www.atmos.albany.edu/student/nschiral/research/gwo/ncep_ncar_archive/

[Summer Sun]

The northerly for next weekend has gone on this run instead replaced by an easterly with some warmer air the risk of thunderstorms increases again towards the south and south east initially but like yesterday it quickly leaves as things turn fresher with a north easterly flow

 

 

If this was winter the easterly wouldn't arrive but you wouldn't bet against it happening seen as its summer

 

UKMO on the other hand has the high closer to the south west

 

Edited June 6, 2015 by Summer Sun

[knocker]

Oh the dangers of analysing each six hour run to death a week before zero hour.

Charts weatherbell

Edited June 6, 2015 by knocker

[Eugene]

GFS 12Z has a 1960's summer vibe about it, lots of northerly blocking and winds from a northerly quadrant.

[stodge]

Evening all

 

http://www.cpc.noaa.gov/products/precip/CWlink/pna/new.nao_index_ensm.html

 

The NAO goes positive again this week before a sharp drop into negative territory and then, after mid month, a huge scatter reflecting a lack of any clear signal.

 

http://modeles.meteociel.fr/modeles/gfs/runs/2015060612/gfs-0-120.png?12

 

This may surprise some but an NAO Positive chart with little or no LP in the Atlantic and the HP, though not orientated well for the UK synoptically is right where it should be as a feature.

 

http://modeles.meteociel.fr/modeles/gfs/runs/2015060612/gfsnh-0-300.png?12

 

Oddly enough, I think this illustrates the uncertainty very well. The Azores HP isn't rarely a feature and the trough over Scandinavia is throwing out areas of LP running north to south down the North Sea. Slack pressure to the NW and there's no real sign of strong blocking and the Atlantic isn't doing much either.

 

However, there is a signal of more energy coming off eastern Canada in FI and perhaps starting to lower heights into Greenland and encouraging the Azores HP to develop back NE. Those looking for potentially warm and settled conditions will welcome this and rightly so - it's not a hot feed off the Continent by any means but it would represent a positive development off a GFS 12Z which, in the medium term, doesn't look brilliant for England in particular.

 

Yet we have huge scatter on the NAO from +1.5 to -3 which tells me the only confidence is a lack of confidence into the last third of the month at this time.

[Frosty.]

Most of the week ahead looks very pleasant with spells of very strong sunshine on Gfs 12z, I think it's best to enjoy what we know is coming in the reliable timeframe, which is fine and pleasant for most of us.

[I remember Atlantic 252]

Most of the week ahead looks very pleasant with spells of very strong sunshine on Gfs 12z, I think it's best to enjoy what we know is coming in the reliable timeframe, which is fine and pleasant for most of us.

 

that's right Frosty! my ideal summer weather, no humidity, warm days light, preferably no wind, surely nobody can dislike 20C, sunny and no wind in Summer?