Model Discussion - 27th July

[damianslaw]

Models showing a continuation in the changeable theme. Brief temporary ridges the order of the day with trough action stubbornly persistant to our NW and the azores high locked in the same position it has been in all summer i.e. not in a conducive position to deliver any strong robust long lasting ridge development over the country.

GFS keen on developing another deep low pressure system later next week. ECM less keen. UKMO appears to be siding with GFS.

All preety standard average fare for mid august, but dissapointing all the same for those wanting any decent very warm dry sunny weather.

[mushymanrob]

Morning Mushy,

Not wishing to be pedantic, but I can't see what you're describing 15c uppers wise across any of England, let alone most of it?; I've posted the charts I'm looking at to illustrate my confusion?

Don't get me wrong, I'd love to see that, but I can't...

I think rob must have had yesterday's 12z run in his cache.

how odd.... i use wetterzentrale every morning, so that was the run i was commenting on and without the time to play around posting charts i understand the confusion. not sure when the 00z and 12z come out but i view sometime between 6.45 and 7.30am. the 15c uppers were there... im not drunk! honest!

anyway it matters not now as as expected the ecm was way out of kilter and the gfs was on the ball along now with the ukmo. another rather ordinary week ahead, eyes to the west for more average, normal mid august weather that will generally favour the south and east for warmth and sunshine whilst the north and west will be wetter cloudier and cooler... but never too bad .

theres still no sign of anything different in the models, and tbh, i dont care now... it can cool off for me.

Edited August 14, 2011 by mushymanrob

[snowingman]

... the cool off to autumn has begun...

the atlantic looks more agressive now with deeper systems forming and moving towards us (especially north) after 7 day period..

also cooling down now in far north! 0 C more prominent north of Iceland...

no significant heat at all for anyone, cooler 12noon temperatures are evident...

what a rubbish summer we've had

[Summer Sun]

Heavy rain and Gales for Scotland if this comes off,

http://www.wetterzentrale.de/pics/Rtavn1621.png

http://www.wetterzentrale.de/pics/Rtavn1861.png

The rest of FI is best described as "Changeable"

[Gibby]

Good morning.

GFS this morning shows a changeable week to come though with a lot of dry weather for many southern and eastern regions. With winds basically from a westerly quarter exposed Western and Northern coastal counties will always be cooler and fresher but parts of the south and east could become quite warm with time. There will be some rain at times in the North and West especially on Tuesday as a small Low pressure system runs NE and a more generally windy and unsettled spell of weather looks likely late in the week in these same NW areas as a deep Low pressure passes NE close by. In FI the North/South divide continues throughout with the North having outbreaks of rain or showers for much of the time under a persistant westerly flow while the South continues to see the best of dry and bright and sometimes warm conditions though even these areas don't remain immune from at least a little rain.

UKMO also shows a changeable spell of weather in the coming week. As per GFS there will be a lot of dry weather for the South but some rain is likely later on Tuesday and the chance of scattered heavy showers through the midweek before another ridge develops close to southern Britain by the weekend. Winds will be fairly light through the week, especially in the South and it will feel warm in any sunshine.

The Fax Charts today show a weak westerly flow over today and tomorrow followed by the passage of a warm and cold front over Tuesday moving NE over all parts. Once cleared pressure patterns remain slack with a waving thundery trough close to the SE on Thursday bringing the risk of thundery rain there through the day

ECM this morning looks a lot like GFS with the frontal system on Tuesday shown to bring the risk of rain for all with perhaps a close shave for southeastern areas with thundery conditions the other side of the channel midweek before the pattern evolves that we have all become accustomed to so much this summer of Low pressure to the NW with troughs occasionally moving east in the flow. There would be a return to frequent outbreaks of rain in the North while the south see far more occasional rain in longer brighter spells with temperatures close to normal.

Nothing excited to shout about within the model output this morning with no particular weather type taking overall control. Instead we continue to see changeable conditions with rain and sun at times with the usual scenario of the North seeing the most rain and the south seeing the best of the drier, brighter and warmer spells.

[Summer Sun]

This week aint looking too bad really apart from Tuesday there should be plenty of sunshine around much more than what the previous 2 weeks have delivered, temperatures won't be special but i'd say high teens to low 20s for the North and low to mid 20's in the south. As we move into the weekend low pressure is over Scotland so a wet weekend to come here further south it should be dry with temps in the low 20's.

The rest of GFS FI aint too bad really,

http://www.wetterzentrale.de/pics/Rtavn2161.png

http://www.wetterzentrale.de/pics/Rtavn2401.png

http://www.wetterzentrale.de/pics/Rtavn2641.png

http://www.wetterzentrale.de/pics/Rtavn3361.png

I've saw worse than that this summer!

[Milhouse]

Indeed Gavin, i can see a fairly pleasing week of average temperatures and decent amounts of sunshine. Tuesday looks the wettest day but even then i can see the SE remaining mostly dry. Wednesday is another dry and reasonably warm day, as is Friday but a scattering of showers can be expected on Thursday. Temperatures remain average throughout so 22/23c will be achieved every day i expect which will feel warm given winds will be fairly light.

[Thundery wintry showers]

I agree with the general synopsis of a bright day with isolated showers tomorrow and fairly wet on Tuesday (except for Ireland where the daily synopsis will be transposed), but I'm a bit wary of a frontal system that is progged by GFS to push into southern areas on Wednesday:

http://nwstatic.co.u.../78/h500slp.png

http://nwstatic.co.u...2/78/ukprec.png

(Note that the precipitation shown for Scotland and northern England represents just a scattering of showers).

In my experience those southerly tracking fronts often get toned up at short notice and I won't be surprised if we see the system head NE into the North Sea providing a slow moving overhang of cloud across some eastern parts of England on Thursday. Thus, in my view the latter part of the week is in doubt across the southern half of England in particular. However, I'll be surprised if it ends up affecting Scotland or the northern third of England, where Millhouse's assessment looks odds-on to end up close to the mark- temperatures will probably only be about average, but the key is light winds under a weak ridge of high pressure.

[Gibby]

Good evening.

GFS this evening looks not dissimilar to the 00z output up to the weekend with a trough of Low pressure crossing NE on Monday night and Tuesday with rain from this for many though chiefly in the North and West. Once passed the weather brightens up for many though there may be a risk of some rain in the SE for a while late Wednesday and Thursday. Then as the weekend approaches Low pressure to the NW brings a front east across Northern and western areas with rain and brisk west or southwest winds for a while. Later in the weekend the Low moves further away North with high pressure nudging up from the South again. Through FI the basis of Higher pressure close to the south and Low to the NW remains with the best of the fairly benign weather pattern in the south while the North sees further rain at times and evntually joins the rest of the UK in settled conditions as high pressure develops over the UK.

UKMO's 12z shows a frontal system crossing the UK on Tuesday with rain for many for a while before a couple of non-descript days develop under slack pressure with sunny intervals and the chance of showers locally. A weak ridge then crosses east before the weekend ahead of an Atlantic depression which pushes its influence into the UK for the weekend in the shape of increasing SW winds and rain for the North and West though the South and East would most likely stay dry.

ECM shows rain on Tuesday as well as a frontal system crosses followed by a couple of days of sunshine and scattered showers, especially in the SE before a ridge on friday gives a dry day with sunny spells. Over the weekend Low pressure moves east to the North of Scotland with westerly winds and rain bearing fronts crossing east, most active in the North. By the start of the new week the south still looks quite dry for a while but as time passes Low pressure to the SW of Ireland becomes dominant as rain pushes North and East across the south.

The earlier predicted warm spell for later this week seems to have evaporated along with the potentially thundery weather the charts were showing a few days ago. Instead things look a lot less interesting weatherwise with a lot of dry weather around with some bright sunshine at times but not the high temperatures, this weather will be mixed with periods of less settled weather with some rain at times and breezy conditions too in the North and West.

[vortex_liam]

I reckon that tomorrow the Low pressure with the bulk of the rain will move up into the south west of England and die down and split up into many showers, some heavy some not. Also the showers along the NW coast will break up during the course of the morning.

[damianslaw]

Very little change in the models today. All show a continuation in the changeable rather average conditions for the foreseeable future. Not much get excited about at the moment - hence how quiet it is in the thread today. Must be one of the quietest weekends for activity all year - not surprising given we are slap bang in the middle of the holiday season.

I'm struggling to say much else other than it could be worse but also a lot better..

Models show a very poor outlook next weekend - a washout one for the north!

[anvilhead]

interesting though that the 20c+ 850 spike on one of the 12z ensemble members ties in with 15c 850's on the 18z gfs op at 240 Hours -

[mushymanrob]

Very little change in the models today. All show a continuation in the changeable rather average conditions for the foreseeable future. Not much get excited about at the moment - hence how quiet it is in the thread today. Must be one of the quietest weekends for activity all year - not surprising given we are slap bang in the middle of the holiday season.

I'm struggling to say much else other than it could be worse but also a lot better..

Models show a very poor outlook next weekend - a washout one for the north!

gotta fully agree.... pretty pleasant easy going weather for the coming week....

[Gibby]

Good morning. A new working week. Lets see what the big three have on offer this morning taken from the 00zs.

GFS shows a trough crossing NE tonight and tomorrow bringing some rain and drizzle NE through most areas though precious little rain for the SE. Thereafter, it becomes basically dry with light winds, sunny spells and no more than the odd shower or two here and there up to the weekend. By Saturday a deep Low to the NW influences the weather for Northern areas with fronts bringing rain and fresh breezes eastwards from time to time. Further south still close to high pressure to the south sees the quiet weather continuing through the weekend. Through FI Low pressure continues to flirt with the UK with the North continuing to see wind and rain at times while apart from the odd trough crossing east in the south at times the weather here would continue to predominate dry. Temperatures throughout would continue to be near to normal away from the rainy NW.

UKMO also shows a weak set of fronts crossing NE tomorrow with rain and drizzle for the North and West while the South and East while cloudy stay largely dry. From Wednesday on a ridge builds over the UK with dry and bright weather for most for the rest of the week and weekend in the south though the odd shower couldn't be ruled out. In the North though things come a little more unsettled over the weekend as Low pressure to the NW brings some wind and rain there.

The Fax Charts show that once tomorrows fronts have cleared the weather will become dominated by a weak ridge from the SW with dry bright weather generally. A trough close by in the English Channel could mean more cloud for the south Wednesday and Thursday with maybe a little rain in the far SE for a while.

ECM also shows the same sequence of events through the week with the weekend becoming quite warm in the south for a while over the weekend. Next week then shows a potentially thundery trough cross England and Wales with some sporadic rain or showers before the staus quo returns of high pressure to the South and Low pressure near the NW midweek next week.

A fairly benign weather pattern is on the cards for the next 10 days or so. There will be a lot of pleasant days in the south while the North may see more cloud, wind and rain at times as the Atlantic train rolls by to the north. Temperatures will remain fairly average though some warm days will occur in the south while some equally cool ones occur in the NW under any persistant wind and rain spells.

[anvilhead]

06z rolling out. Seems to be stuck on T120, but we're not a million miles away from a short lived spanish plume imo -

[Thundery wintry showers]

Still a fair amount of uncertainty over the latter part of the week due to that complication to the SE, with GFS suggesting a cooler, cloudier and wetter day for many on Thursday, though Wednesday and Friday look mostly sunny and dry with just a scattering of showers in the north, and average temperatures. The UKMO makes rather more of that feature to the SE than the GFS, so Thursday in particular looks uncertain.

Some interest in the weekend's outputs. I agree with Anvilhead that we get quite close to a Spanish plume setup- the ECM seems more bullish about this than the GFS- and thus while yesterday's runs overwhelmingly suggested a dull wet windy weekend for most, current progs are heading towards a NW-SE split with some warm sunshine to the SE of the dividing line, e.g. maxima of 25-26C are suggested by GFS for the south-east corner on Sunday. The precise positioning of the dividing line is open to question, and it may well end up as one of those "southeast takes all" setups, but certainly worth watching.

[William of Walworth]

Yes, it's all about positioning now, isn't it. Not too much of a stretch to evolve from current modelling to end up with the synoptics offering benign conditions over the weekend for more than just the SE.

Can't see them heading too far North at all though I'm afraid.

[Uncle_Barty]

Interesting to note that the MJO has suddenly moved from the neutral area into Phase 2, which suggests high height anomalies over the UK stretching NW over Grenland and down through Canada to the Mid-west, and low anomalies over Newfoundland and eastern Europe into Russia.

Make of that what you will!

[Summer Sun]

Looks like a decent weekend for most away from Scotland,

http://www.wetterzentrale.de/pics/Rtavn1261.png

http://www.wetterzentrale.de/pics/Rtavn1501.png

Even into next week the same patteren continues,

http://www.wetterzentrale.de/pics/Rtavn1741.png

http://www.wetterzentrale.de/pics/Rtavn2161.png

Into FI and the settled look continues,

http://www.wetterzentrale.de/pics/Rtavn3121.png

http://www.wetterzentrale.de/pics/Rtavn3361.png

http://www.wetterzentrale.de/pics/Rtavn3601.png

http://www.wetterzentrale.de/pics/Rtavn3841.png

The best update by far for a long time.

[bluearmy]

Interesting to note that the MJO has suddenly moved from the neutral area into Phase 2, which suggests high height anomalies over the UK stretching NW over Grenland and down through Canada to the Mid-west, and low anomalies over Newfoundland and eastern Europe into Russia.

Make of that what you will!

currently quite low aplitude phase 2 jim and looking at the various model forecasts, it heads into low amp phase 1 or runs slowly through fairly low amp phase 2. not sure whether we can take too much from this. generally, the anomolies on offer in the second week look to be fairly weak which offers an even chance of either a more or less settled scenario occuring or a continuation of the changeable conditions that have prevailed for much of the past few weeks.

noticed some strong shortwaves just north of scotland on the spreads towards month end on the 00z naefs. lets hope not eh ?

[cyclonic happiness]

The charts have been so stagnant and so boring for so long, I've not even bothered to look at them for a couple of weeks.

Why is everything so static atm?

Edited August 15, 2011 by Paul
Removed off topic lines

[Milhouse]

GFS 12z is a good run for warmth with the heat remaining over much of England and Wales until Monday. Infact we arent a million miles away from the set up that brought 33c to the SE on 27th June. Once again we have a pulse of very warm air coming up from France which the 12z suggests might clip the SE but the main bulk of the heat will be kept over Europe where it will become very hot.

UKMO looks to be leaning towards some more widespread warm and settled conditions for the weekend.

[Backtrack]

The rain band modelled by the 12z looks OTT in my opinion. Looking at the radar right now, and the chart for 21:00, there's a lot of difference. Would not surprise me if some of England missed out on the rain completely tomorrow.

[Snowmad79]

The rain band modelled by the 12z looks OTT in my opinion. Looking at the radar right now, and the chart for 21:00, there's a lot of difference. Would not surprise me if some of England missed out on the rain completely tomorrow.

Indeed, any showers in the coming week look to be breif/ intermitten (if thats the word) rather than persistant which has been the story of 2011 precip so far. I think most are looking south right now in awe rather than above, with all the weird "40 year snow" stuff going on around the southern hemisphere.

Wondering if our winter will end up a vastly dry one again.

[Gibby]

Good evening.

GFS tonight shows a trough of Low pressure moving NE tonight followed by a weak cold front crossing east tomorrow. Through Wednesday this will lie through the English Channel with the risk of small disturbances running along it allowing cloud and some rain to return to southernmost areas over Wednesday and Thursday. Thereafter a ridge moves across from the west with a high centre forming to the SE through the weekend. Some warm and settled conditions would set up for the south and east for a while before a cold front crossing east early next week brings the more unsettled and cooler conditions in the NW across all areas. From thereon and through a part of FI a slack Atlantic flow engulfs the UK for quite a while with occasional rain though a lot of drier weather too in temperatures close to normal. Towards the end of FI a large high pressure area over the UK settles the weather down for all with a fine and warm and sunny end to the month for most.

UKMO tonight also shows a frontal set move through the UK over the next 24hrs followed by a period of slack pressure with a stationary front in the English Channel. So some rain and drizzle overnight and tomorrow will clear from the west late tomorrow. Then on Wednesday and Thursday fair weather seems likely though a cloud overhang from the front in the channel could maintain a lot of cloud in Southern England with even a little rain for a while. Following the fronts departure will be a ridge moving up strongly from the SW on Friday with the weather becoming warm then very warm with sunny spells over the weekend before the chance of something thundery looks possible shortly afterwards.

ECM looks very similar up to Saturday with the South and East developing a couple of very warm days at the start of the weekend. However, it then shows a cold front crossing East into the hot air sparking of some thundery outbreaks, especially for eastern areas. In addition a Low cell is shown moving North up the east of the UK enhancing the thunder risk before a cool NW airflow develops behind the trough through the early days of next week. By midweek pressure is then high to the SW with the cool and fresher NW breeze giving way to another short warm spell for the south and east at least in about 10 days time.

The pattern looks pretty much set tonight on the progression of events between now and Saturday with the proviso of the stalled English Channel front on Wednesday and Thursday not developing differently than shown in any way. Then with high pressure near SE Britain over the weekend some very warm air could well affect the east and south. Then both ECM and GFS (ECM a day earlier) brings a cold front east to bring rain and perhaps thundery weather to many areas early next week before a return to warm conditions again if ECM is to be believed and eventually via GFS later in FI.