Model Output Discussion 22/07/12 Onwards.

[Frosty.]

Hi all,

Here's todays 8-10 Day model based video:

Cool And Unsettled To The Middle Of August? http://gavsweathervids.com/

All looking rather grim unfortunately.

Latest Ecm 12z shows a more settled interlude and briefly warming up in the south (850's look briefly high) but then a risk of a thundery breakdown followed by cooler northerly winds. A trough looks like becoming slow moving over the uk in the coming days with a showery set up and average temps or slightly below but then there is a good chance of a ridge covering most areas by midweek but then unsettled again to end the week.

Edited July 31, 2012 by Frosty039

[shedhead]

I am not confident of this jetstream northward shift. Its going to be interesting to see what happens BUT I suspect that a southerly tracking jet will dominate. The PDO seems to be in a less -ve state so maybe we'll get some improvement with HP not so dominant to our NW. Models show no encouraging signs as yet.

BFTP

Some of us have been banging this drum for a while now Blast, much of which has either been ignored or lambasted, but the southerly tracking Jet/unsettled weather is certainly here to stay for at least the first half of Aug. Thereafter I still expect a slow erosion of the pattern, which should ultimately set us up for a half decent final week to 10 days, followed by a cracking Sept.

[William of Walworth]

How do people reconcile Matt Hugo's thoughts with the HPish themed ECM output for around 9 August that Frosty was discussing?

Haven't yet had time to check updates more recent than those charts, but I have to say that if any element of a HP influence, even just for the S, next week is still being shown in even some of the latest models, then several peoples' confidence that the bulk of August is an utterly unsettled write-off for almost all of us may, just may, end up looking overconfident.

Remind me how much the output over successive recent days has been switching about between very unsummery and somewhat less so (for some) for beyond this current week??

Us hopecasters (or despair avoiders?) get criticised on here and sometimes correctly so. We sometimes risk looking over hopefully at HP hints in FI at this time of year, admittedly.

But others can at times show a tendancy almost to want to dismiss any possibility of any HP at all, and when such does begin to show nearer the reliable timeframe, automatic assumtions that HP will be ultra-transient and melt away in moments, do sometimes get posted ... it has just occasionally been known for HP to be resilient enough to alter the track of following LP systems quite markedly (this is not a forecast, just a general statement).

Those inclined to be 'writer-offers' of whole blocks of time after particular sets of daily operational outputs should be adding some caveats and cautions against their readings IMO.

FI is FI for both pessimists and optimists and too much of either is not realistic when the models show such contrasting signs from day to day.

Contrasts that many models have been showing (beyond the reliable timeframe) recently!

[Frosty.]

Maybe briefly very warm in southern england next thursday but the 850's are disappointing for many although the models have chopped and changed a lot today from an unsettled outlook (00z) and then settled (6z) so IMO nothing is decided yet.

[The Northern Ramper]

Some of us have been banging this drum for a while now Blast, much of which has either been ignored or lambasted, but the southerly tracking Jet/unsettled weather is certainly here to stay for at least the first half of Aug. Thereafter I still expect a slow erosion of the pattern, which should ultimately set us up for a half decent final week to 10 days, followed by a cracking Sept.

I would like to see evidence of this lambasting, most people are probably failing to comment out of acceptance following a mainly miserable two months.

Edited July 31, 2012 by Snow Guy

[William of Walworth]

Had a quick scan of some of the lastests, and I still think they support rather than contradict my general thoughts above.

Glad to see that well known Northern realist Frosty sticking to his guns on some HP next week and that some evolutions still seem to support his readings

Some of us have been banging this drum for a while now Blast, much of which has either been ignored or lambasted, but the southerly tracking Jet/unsettled weather is certainly here to stay for at least the first half of Aug. Thereafter I still expect a slow erosion of the pattern, which should ultimately set us up for a half decent final week to 10 days, followed by a cracking Sept.

Interesting thoughts and I can sort of see which output you're getting them from,. So please don't think, from my rant! above, that I'm in any kind of certainty that you're wrong.

But I do genuinely wonder whether improvements may not arrive somewhat sooner than you're predicting at the moment, at least for some of us. Given that not all models are singing from the same hymnsheet yet regarding the 'wait until 15 August or later for summer' idea.

.

Maybe briefly very warm in southern england next thursday but the 850's are disappointing for many although the models have chopped and changed a lot today from an unsettled outlook (00z) and then settled (6z) so IMO nothing is decided yet.

That very different from some earlier runs today, sadly for some of us, but as you say and I did, plenty of chops and changes have been the recent story ....

[Methuselah]

I must agree. I think that most of us are guilty of seeing only what we want to see, on occasions: 'signs' of hot weather, in summer are nicely counterbalanced by 'signs' of a Scandi High, come winter...Hence the continued requests for 'objectivity' in model-reading???

Now for that all-important Azores-Scandinavia HP link-up not shown in FI!

[ohno]

I think its the case of looking for summer weather in the "summer".. Instead of the drab 12c with a cold wind on the 31st of July..

Nothing wrong with looking at models and trying to see if its going to get warmer and drier...

[Bristawl Si]

but the southerly tracking Jet/unsettled weather is certainly here to stay for at least the first half of Aug.

That's a brave call forecasting ahead, for the next 15/16 days.

[Jason T]

It seems to be pretty much the norm now for LP after LP,This may sound a dumb question but what is stopping the jet stream climbing.Obviously if im right the general scenario is the higher the jet stream the steadier a pattern is. What are the influences?.Apologises mods for maybe wrong thread.

Jason

[Thundery wintry showers]

To my mind this thread generally mutates into a high pressure watch when subjectivity and teeth-gnashing are rife. Similar to how the fabled "Scandi" high is assumed to bring lots of snow in winter and anything involving a westerly is written off, a high pressure in summer is assumed to bring warm dry sunny weather while anything involving low pressure is written off. When posts become focused more on model output analysis, as was generally the case about a week or two ago, those over-simplistic perceptions and biases are less prominent.

There may well be something for the convection/storm lovers to watch out for tomorrow in northern England as the cold front pushes eastwards and collides with fairly warm humid air, although the emphasis will be on frontal type rain with some additional heavier showery bursts. In the meantime some sunshine is likely to break through over East Anglia and the southeast which may produce highs of 22-24C. Subsequently, Thursday looks like being a straightforward day of sunshine and showers, most of the showers in central and southern parts of England, and with highs of 19-22C.

The detail for Friday onwards continues to look unclear due to a weak front wrapped around the depression which may introduce cloudier conditions at times with showers merging into longer spells of rain, as well as suppressing significant thunder potential (a common theme during this cloudy summer in general). However this low looks like being a bit weaker and further north than the one at the start of July as it slides across the British Isles so it probably won't generally be as cloudy as the first fortnight of July was, and daytime temperatures will probably be a little higher at around 18-22C. "Unsettled" is certainly a fair assessment; sunshine and rainfall amounts though will be hard to pin down.

[MP-R]

For most of this summer, Jason, it's been the presence of northern blocking, mainly over Greenland. That accompanied with an Azores high sort of funnels low pressure through the middle. The models are showing a similar pattern but with a high over eastern Europe and Russia too which effectively halts the low in place over the UK.

FI has often shown heights falling significant in the Greenland region however yet it still remains as unsettled in the UK as with heights in that area so that's what I'm not so sure about. I think if the jet powers up and moves north like it did in the last week of July, then a similar spell of weather could occur around the 10th-15th. The models were hinting at this earlier.

I don't however see how this pattern should magically just disappear as we move into September. Last year it became even more unsettled into September.

[Thundery wintry showers]

Sticking my neck out a little for Friday and the weekend, the movement of the low pressure and associated fronts suggests a bright, showery and fairly warm day for eastern areas on Friday (continuing on from Thursday) but with cloudier conditions and showery rain for western areas associated with the trailing occluded front, and these cloudier conditions will probably move into eastern areas on Saturday with brighter showery weather returning in the west. For Sunday, at this range, looks like being back to straightforward sun/showers.

[shedhead]

That's a brave call forecasting ahead, for the next 15/16 days.

Is it BB?

Much the same was said by some last week, when I hinted at the first third of Aug being written off... but here we are now looking at that being a near certainty.

William of Walworth, on 26 July 2012 - 05:20 , said:

What the hell happened to that GFS FI-candy (for around 8 August) that Summer Sun was posting as recently as yesterday?

I don't get such a violent switch now, leading one or two people above overconfidently (IMO), and on just this latest admittedly worrying-looking set of runs, to write off a third (!!??) of August already.

It's not even 1st August yet!

I'm reluctant to credit such a comprehensive write off of such a big chunk of a month on what after all is ONE set of runs!!

Apply more caution I'd advise, and don't over-interpret yet -- FI operationals can over ramp HP influence sure, but the same can be true in reverse, very possible that these rainy deep lows for later on are being overcooked too.

Edited July 31, 2012 by shedhead

[Cheese Rice]

The models don't seem as bad depending on where you live. I originally expected temperatures to reach around average across all areas but it seems central and western parts of England/Wales/Scotland are plagued by below average temperatures. If it's any consolation the outlook does appear to be improving in the sense that we may see a more showery flow with low pressure anchored to our south west, could finally see some long spells of sunshine across the far north.

In the short term Yorkshire, East Anglia and the South East seeing the best temperatures around 19-22.c

[Bristawl Si]

Is it BB?

Much the same was said by some last week, when I hinted at the first third of Aug being written off... but here we are now looking at that being a near certainty.

William of Walworth, on 26 July 2012 - 05:20 , said:

What the hell happened to that GFS FI-candy (for around 8 August) that Summer Sun was posting as recently as yesterday?

I don't get such a violent switch now, leading one or two people above overconfidently (IMO), and on just this latest admittedly worrying-looking set of runs, to write off a third (!!??) of August already.

It's not even 1st August yet!

I'm reluctant to credit such a comprehensive write off of such a big chunk of a month on what after all is ONE set of runs!!

Apply more caution I'd advise, and don't over-interpret yet -- FI operationals can over ramp HP influence sure, but the same can be true in reverse, very possible that these rainy deep lows for later on are being overcooked too.

I think you were writing if off and hinting at it being as bad as June/early July - i hardly call a sunshine and showers scenario a 'write off' - granted there's no hint of a sunny, hot spell but i'd hardly call it a write off.

I suppose it boils down to what people view as a "write off".

[ANYWEATHER]

I think you were writing if off and hinting at it being as bad as June/early July - i hardly call a sunshine and showers scenario a 'write off' - granted there's no hint of a sunny, hot spell but i'd hardly call it a write off.

I suppose it boils down to what people view as a "write off".

What I can see developing again is Southerly tracking Lows both hinted at by gfs and ecm in the not to distant future which is very similar to the theme of this Summer. All a long way off in terms of detail but I do see a "trend" developing as regards this! If this scenario develops the a North/ South split is the outcome with the likes of Northern Scotland being dryer, the Southern half of the Uk seeing again way above average rainfall and again problems with flooding etc ,Im afraid. Im by no means a doom and gloom poster on here, but unfortunately I see nothing unfortunately showing Summer for a while at least for the majority of the population.

Edited August 1, 2012 by ANYWEATHER

[valiant]

I think you were writing if off and hinting at it being as bad as June/early July - i hardly call a sunshine and showers scenario a 'write off' - granted there's no hint of a sunny, hot spell but i'd hardly call it a write off.

I suppose it boils down to what people view as a "write off".

Right on.

What's with this (trendy?) preoccupation with the jet stream? I know it dictates what sort of weather we get AFTER it positions itself - but isn't its final position pretty random? In my relatively uninformed mind I see it originating thousands of miles away and with a tendency to act like a hose pipe snaking around on the yard when you turn it on.

Or does it carefully pick its way around high and low pressure areas in a way we can easily forecast.......

Edited August 1, 2012 by valiant

[Frosty.]

I think there are reasons to be optimistic about the 00z models today, there are growing hints of pressure rising and later next week it could become hot in the south which the ecm has built on since the 12z yesterday evening although it shows a thundery breakdown fairly quickly followed by another trough moving in, the gfs 00z takes a different route and is indicating a more anticyclonic outlook beyond the unsettled spell with increasing heat for the south and also becoming warmer in the north BUT in the meantime we have a slow moving trough to deal with in the next 3-5 days with plenty of rain and fairly average temps but then possibly a big improvement further into FI.

Edited August 1, 2012 by Frosty039

[Methuselah]

I certainly wouldn't call the first third of August a write-off...The latest GFS might not be showing wall-to-wall sunshine & record-breaking high temperatures, but - since when - did that recipe ever describe the typical British summer?

Can we please at least try and get some kind of perspective here? One person's 'horror show' is another's 'Utopia' after all...

[Uncle_Barty]

Right on.

What's with this (trendy?) preoccupation with the jet stream? I know it dictates what sort of weather we get AFTER it positions itself - but isn't its final position pretty random? In my relatively uninformed mind I see it originating thousands of miles away and with a tendency to act like a hose pipe snaking around on the yard when you turn it on.

Or does it carefully pick its way around high and low pressure areas in a way we can easily forecast.......

Nothing trendy about the Jet-stream...

It drives our weather as we have all found out this summer to our cost, hence it has been a topic of conversation.

Question is - has the persistent block over Greenland pushed it south, or has the jet's southerly position allowed the Greeny high to form?

Chicken and egg.....

[shedhead]

I think you were writing if off and hinting at it being as bad as June/early July - i hardly call a sunshine and showers scenario a 'write off' - granted there's no hint of a sunny, hot spell but i'd hardly call it a write off.

I suppose it boils down to what people view as a "write off".

I've never suggested or even hinted that the upcoming weather will be anything like as bad as June's was, in fact I've made posts in this and the previous thread saying the polar opposite. You are however right to question what does or does not constitute a write off, that like much else with the weather is subjective, but I think most would recognise the current/upcoming spell of LP domination and a persistent southerly tracking Jet is pretty dire for what is supposed to be the height of Summer.

[Summer Sun]

A few decent days from GFS 00z

[shedhead]

I certainly wouldn't call the first third of August a write-off...The latest GFS might not be showing wall-to-wall sunshine & record-breaking high temperatures, but - since when - did that recipe ever describe the typical British summer?

Can we please at least try and get some kind of perspective here? One person's 'horror show' is another's 'Utopia' after all...

Let'a hope you and the rest of the team remember this come Winter Pete...

[Snowmadsam]

Let'a hope you and the rest of the team remember this come Winter Pete...

Don't worry we will...it will be our motto(most likely!)

As Summer Sun has said we may get a few decent days if the 00z came off...but that all depends where you are