Model Output Discussion 01/06/2012

[Milhouse]

Early next week it looks like pressure will attempt to rise from the west. Whether we get a decent settled spell depends on whether we can get the copious amount of high pressure to our north west to link up with the Azores high to the south which also looks well placed. The GFS has been the model that has been leaning towards this outcome the most. We just need high pressure to build strongly enough to block the track of low pressures towards the UK.

Monday to Wednesday look reasonable next week on the ECM with a weak ridge before the next low brings some potentially very warm conditions. Thereafter it turns vile pretty quickly

[Summer Sun]

ECM send's another low our way later next week, what is it with Friday's and LP systems lately?

Edited June 20, 2012 by Gavin D

[phil nw.]

Just a request on John H`s problem and replies on here.

There is a thread open for any further posts on this

http://forum.netweather.tv/topic/73613-web-security-problems/page__pid__2319598#entry2319598

I am sure John appreciates all the reponses but in order to avoid cluttering this thread up please use the link above for any further postings on this or indeed as Shed. has said above try the PM system, if you prefer.

Thanks all.

[phil nw.]

No real change to the outlook for the next week or so according to the 12z runs it seems.

The approaching low off the Atlantic will kick of another wet period with rain moving up the country tonight and tomorrow followed by showers for the weekend.

Into next week and as the main low moves away towards Scandinavia the flow turns more north westerly keeping temperatures depressed and with a continuing risk of showers or longer spells of rain.

This UKMO NH chart shows quite well how we continue to be affected by this persistent upper trough at T120hrs.

keeping the UK and NW Europe on the cool side of the jet stream.

[OldMetMan]

Model output today continues to intrigue.

There is a reasonable consensus in the short- to mid-term - continuation of the marked meridional flow all the way from the US to Europe with the UK still stuck under the eastern flank of the upper trough, hence the continuing run of LPs coming at us. The one developing to our SW at the moment is showing growing dense high cloud on satellite - I think the MetO warnings are more than warranted.

There are a few similarities in the mid- to long-term model output that look plausible. If anything, the meridional flow may increase in the near-term. However, the models are suggesting that eventually we may get a cutoff upper low to our SW which may allow for pressure to build over the UK. The ECM though is keeping us firmly stuck under the influence of the upper trough - personally I think it's a bit extreme - but we'll see.

I am convinced that the Atlantic tropical storm development will have some bearing on our weather in the next 2-3 weeks. TS Chris is about to go extra-tropical but it is taking an easterly course which is only serving to strengthen the southern arm of the jet so will not do much to help from our point of view. However, the GFS shows a significant LP in the long-term up the east of the US and Canada which suggests to me the LP depicted would likely be of tropical origin - perhaps based on the possible development that is taking place in the Caribbean at present. It is worth noting that having 3 named tropical storms at this point in June has only happened twice since the 19th century. All 3 have formed in similar locations - just E of the US - so I think if this trend continues, it could affect things here by pumping very warm air NE into the NW Atlantic - enough maybe to disrupt the blocking pattern, or re-establish it in a more favourable pattern from our point of view. Pure speculation I know but I feel it needs something significant like that to shift the stuck pattern we are in.

Meanwhile, more wind and rain - the drought seems a distant memory now!

Edited June 20, 2012 by OldMetMan

[Slowpoke]

18z looks good for next week. Light winds, sunshine and warm temperatures from Monday until Thursday. Keep your fingers crossed guys! Possibly a few scattered afternoon showers bubbling up, maybe even developing into thunderstorms. Tuesday onwards looks very summery! Low-mid twenties for England and maybe parts of Wales. Widespread high teens and maybe even locally into the low twenties for Scotland and Ireland. Certainly not a heatwave but it will feel glorious after weeks and weeks of rain. Of course, this is still FI since we need to get this ugly weekend low out of the way. I hope it happens though, we seriously deserve it.

Edited June 21, 2012 by Slowpoke

[reef]

18z looks good for next week. Light winds, sunshine and warm temperatures from Monday until Thursday. Keep your fingers crossed guys! Possibly a few scattered afternoon showers bubbling up, maybe even developing into thunderstorms. Tuesday onwards looks very summery! Low-mid twenties for England and maybe parts of Wales. Widespread high teens and maybe even locally into the low twenties for Scotland and Ireland. Certainly not a heatwave but it will feel glorious after weeks and weeks of rain. Of course, this is still FI since we need to get this ugly weekend low out of the way. I hope it happens though, we seriously deserve it.

With respect, it shows better weather than we've been used to recently, but not exactly settled, warm and certainly not dry.

Monday looks to be a day with average temperatures and a mixture of sunshine and moderate/heavy showers under a slack northwesterly flow. After a cool and clear night Tuesday is then the best day with temperatures of around 19-22C in England and Wales and cooler in Scotland and Northern Ireland. Things then go downhill Wednesday with a small feature crossing central areas with the best weather reserved for Scotland. Temperatures look to be in the mid-high teens in the majority of areas with 19-21C in the south-east corner. Thursday then sees a small feature over England which produces some heavy showers. Temperatures again look close to average with highs of perhaps 19-21C in areas which dodge the showers.

Still, all of this is beyond 120hrs anyway, so it most likely will change quite a bit.

[Slowpoke]

I guess I was getting carried away a bit. But the light winds and lack of frontal rain is what's getting me so excited. After temperatures of 13-15C most days for the last 3 weeks, temperatures of 19-22C will feel fantastic in the light winds. I do believe, under 850s of 7-8C, that parts of England could locally get up to the mid-20s however.

The showers that could be triggered midweek next week could be thundery though, at least in the SE.

But, as I've said myself, we need to get this weekend low out of the way before anything is certain.

[KTtom]

Certianly an improved picture for next week with some potential for decent warmth towards the latter half of next week. ECM does break this down again with the introduction of yet another 'Friday' low pressure system. We seem to be stuck in a very rigid weekly pattern at the moment, the 1 crumb of comfort is the lows seem to be tacking a more northerly track next week.

[Weather-history]

Latter stages of ECM has a hot plume being pulled northwards as low engages it coming into the west. Could go "bang" in that set up.

[Jezzer]

Certianly an improved picture for next week with some potential for decent warmth towards the latter half of next week. ECM does break this down again with the introduction of yet another 'Friday' low pressure system. We seem to be stuck in a very rigid weekly pattern at the moment, the 1 crumb of comfort is the lows seem to be tacking a more northerly track next week.

Have been wondering, while weather patterns are unpredictable is it ever possible that phases of low pressure hitting our shores can be cyclical or are these purely coincidental occurrences of lows approaching on a weekly basis?

[Uncle_Barty]

Coincidental, I'd say. Just happens to be the pattern at the moment.

[Summer Sun]

Could be some big thunder storms if this comes off in the SE

It doesn't last long though

GFS hints at something similar

Longer term though there is no sign of any settled summer weather

http://www.null/ds/gfs.htm

[shedhead]

A rather more interesting ECM this morning which at least hints at a spell of warmer weather from the south, albeit brief, before things again go bang. GFS however continues to stick quite closely to it's previous evolution, building pressure slowly and rather tentatively from the west for a time next week, before the Atlantic stumbles rather than crashes back in at the weekend.

[BLAST FROM THE PAST]

Todays models seem to hint at us going round in circles, I think this pattern remains for a while yet. I've noticed and commented on it that these days when we get into a pattern it seems to entrench itself for a lengthy period of over a month or so and when we eventually shift into a new one then the same happens. That seemed the case last spring, winter and autumn. On that basis I aint looking for summer yet.

BFTP

[Backtrack]

Could be some big thunder storms if this comes off in the SE

It doesn't last long though

GFS hints at something similar

Longer term though there is no sign of any settled summer weather

http://www.jp2webdes...o.uk/ds/gfs.htm

20C uppers with a 19C max showing on the GFS? I think if that 850 chart was correct you could add another 12-14C to that chart.

Edited June 21, 2012 by Backtrack

[Summer Sun]

GFS 06z has got rid of the warmer air idea for next week, there is the odd ridge of HP building along the south but nothing last's long and its all FI

Thats the best I can find for high pressure

Deepest FI continues to look unsettled

Rainfall totals to July 7th

[Rollo]

Todays models seem to hint at us going round in circles, I think this pattern remains for a while yet. I've noticed and commented on it that these days when we get into a pattern it seems to entrench itself for a lengthy period of over a month or so and when we eventually shift into a new one then the same happens. That seemed the case last spring, winter and autumn. On that basis I aint looking for summer yet.

BFTP

The way things are going BFTP it could be quite a long time before any proper summer weather arrives (if it ever does this year).

[shedhead]

Todays models seem to hint at us going round in circles, I think this pattern remains for a while yet. I've noticed and commented on it that these days when we get into a pattern it seems to entrench itself for a lengthy period of over a month or so and when we eventually shift into a new one then the same happens. That seemed the case last spring, winter and autumn. On that basis I aint looking for summer yet.

BFTP

Looking at all the currently available data it's hard to argue with your 'going round in circles' point Blast, that is exactly what the weather appears to be doing. We do indeed seem a long way away from breaking this general pattern atm, with any potential improvents quickly getting dashed by the very next set of runs in many cases, so perhaps this would be a good time to ask Stewart (GP) if he'd be kind enough to give us his latest thoughts.

Edited June 21, 2012 by shedhead

[Scorcher]

I think there has already been an improvement, we've gone from low after low ploughing straight over the top of the UK with little respite to having lows and then ridges of high pressure moving in for a few days and temporarily settling things down and allowing temperatures to rise briefly. This wasn't happening at all before. and the models are showing next week's lows taking a more northerly track so southern areas may have a decent week.

[Optimus Prime]

20C uppers with a 19C max showing on the GFS? I think if that 850 chart was correct you could add another 12-14C to that chart.

There is absolutely zero chance 30c-33c would be reached looking at that chart. You're taking the 850's into account without considering other variables such as rainfall, cloud cover, wind and surface temperature. Going by that chart 18c - 22c.

[Snowy Easterly]

ridiculous differences at just T72, UKMO has a band of rain crossing the whole of the UK, whilst GFS has it skirting the far south

??

[Weather Boy]

I think there has already been an improvement, we've gone from low after low ploughing straight over the top of the UK with little respite to having lows and then ridges of high pressure moving in for a few days and temporarily settling things down and allowing temperatures to rise briefly. This wasn't happening at all before. and the models are showing next week's lows taking a more northerly track so southern areas may have a decent week.

Exactly what I was thinking. It's true to say that, at present, there is absolutely no sign of any long-term settled weather for the UK.

However, at the beginning of the month the jet was essentially over the channel. Last weekend's weather, which for where I was at least (the south) was nowhere near as bad as forecast, the Low was much further north than earlier in the month. This weekend's low (not liking the good weather being in the week and bad weather at weekend) looks to be generally further north with the jet nearer its more usual position. There are hints of a high nudging into the channel pushing the low further north.

I conclude from this that the trend is gradually improving for the south, but for the north, if anything the position is worse, because northern Scotland at least was a long way from the jet earlier in the month, now the jet gets closer to that location, allowing more settled weather in the south, although that is not to say that the south will be immune from showers or frontal systems from time to time and indeed, as I said at the start, heatwaves and the like are very much for far FI, if at all.

In short, still not brilliant, but a gradual two steps forward one back type improvement compared to the start of the month.

Good old SE/NW split anyone? Likely solution for 30 June onwards, IMHO.

Edited June 21, 2012 by Weather Boy

[BLAST FROM THE PAST]

Looking at all the currently available data it's hard to argue with your 'going round in circles' point Blast, that is exactly what the weather appears to be doing. We do indeed seem a long way away from breaking this general pattern atm, with any potential improvents quickly getting dashed by the very next set of runs in many cases, so perhaps this would be a good time to ask Stewart (GP) if he'd be kind enough to give us his latest thoughts.

Indeed Shed, nothing in the wings yet......not obviously anyway. 12z GFS really paints a non summer picture and groundhog day.

BFTP

[Summer Sun]

Pretty unsettled from UKMO tonight could be warmer than of late though more so in any sunny spells, next wednesday see's another low in the atlantic heading our way

http://www.null/ds/ukmo.htm