Model Output Discussions 12z 08/03/17

[Man With Beard]

1 hour ago, cheese said:

Well, let's not get ahead of ourselves - at the moment we are looking at a settled period with temps largely in the mid-high teens, but it is not unusual at all get a period of weather like that in April. Nor is it unusual to get one or two days above 20C.

There is no April 2011 or April 2007 repeat on the cards.

Wouldn't rule it out yet, cheese. Just needs a little trough to get stranded over NW Iberia for a few days ... it's already pushing 80F in Italy and what if that all comes our way???

[damianslaw]

All models showing a change to high pressure taking charge by the end of the week, the question is where will the high want to position itself. At 120 hr / 144 hr timeframe (end of reliable) there are indications of some form of retrogression, with a cut off low feature sat over the mid atlantic, its how this feature interacts with the heights that will determine whether it sinks southeastwards and we draw in a milder southerly continental airflow, or pull in a much colder north easterly continental airflow thanks to a deep trough feature anchoring down through scandi.

By this time of year, high pressure can sit overhead for lengthy periods, and has a greater chance of retrogressing to the NW or building into scandi than during the autumn-winter months, when it rarely manages to hold its ground against the atlantic. 

[Frosty.]

25 minutes ago, Man With Beard said:

 Just needs a little trough to get stranded over NW Iberia for a few days ... it's already pushing 80F in Italy and what if that all comes our way???

Wouldn't that be wonderful, anyway here's hoping the Gfs / Gem are right about a significant warm up next week with winds becoming more southerly in direction and pushing temperatures into the low to mid 60'sF..this weekend looks a beauty, pleasantly warm and sunny across most of the uk after clear, chilly starts.

Edited March 21, 2017 by Frosty.

[ANYWEATHER]

Evening , Despite the very relaxed outlook ,the Ecm shows a potential late cold spell later next week ,It might be a near miss...! it may not .....a very interesting outook

Edited March 21, 2017 by ANYWEATHER

[Frosty.]

Tonight's Ecm 12z ensemble mean indicates a quiet settled outlook with pleasant days, feeling warm in the strengthening late march sunshine and generally light winds but nights look chilly where skies clear with a risk of slight air frosts and patchy mist or fog, especially in rural areas..signs that the far n / w could turn a bit unsettled later next week but that's a long way off..a very nice weekend is on the way with plenty of sunshine.

Edited March 21, 2017 by Frosty.

[geordiekev]

I have to say the outlook from the models looking similar to 2016 with cold easterlies due to the high pressure set ups, just at the wrong time of year again,  especially for seedlings. Will it be a repeat with cold easterlies stretching till July. The seasons defo seem out of kilter if a repeat this year. 

Went to Prague on hope of a snowy birthday only to return last night to find a snowy garden. Weird as must have been a good day yesterday as Solar lights still on at 6am. 

Edited March 22, 2017 by geordiekev

[knocker]

This morning's GFS is still following the prescribed path with the HP replacing the cooler, unsettled, low pressure weather commencing on Friday and becoming well established by the weekend and thus drier and the usual diurnal temp variation

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Essentially the problem appears to be be what it has always been and that is the upstream energy traveling east splitting with some traveling around the top of the HP and the rest to the south. Thus the HP is under stress from two sources which effects it's orientation and position vis the UK. This has been more noticeable on a couple of recent ecm runs with troughs tracking south west to the south east of the UK. This morning the GFS takes the other option, although it does try to phase the LP to the SW and SE, and that is to push the Atlantic further east albeit withe high pressure struggling all the way.

The result of all this is battleground UK with the high pressure hanging in there to the S/SE with the Atlantic impacting the north west. Ergo remaining pretty dry but the occasional ingress of weak systems from the mainly effecting the north west with temps above average but probably some impressive diurnal variations. This is pretty knife edge stuff and the balance of power will quite likely vary in detail run to run.

[knocker]

Further to my wittering above. This morning the ecm again tracks an upper trough around the high and then SW to phase in with the low pressure in that area  So by 12z Monday we have a reinforced cut off upper low to the SW/S about to phase with the Atlantic trough with the high cell maintaining a position to the W/NW of the UK and thus forcing the Atlantic further to the SW With the HP centre tending to drift around to the north the UK will be in a dry easterly regime with the temps quite variable around the average. All this just illustrates how knife edge the detailed evolution is.

Edited March 22, 2017 by knocker

[knocker]

Initially next week the EPS mean is not dissimilar to the det. but it then proceeds to slide the HP SE thus veering the flow SW with some ingress from the trough as well. Ergo portending a not unusual NW/SE split with temps generally a tad above average.

Sidney was all ears whilst getting yesterday's update

 

Edited March 22, 2017 by knocker

[Frosty.]

Lovely weekend coming up, dry and mainly sunny across most of the uk under high pressure, the fine weather continues into next week..nice ukmo 00z.

[frosty ground]

16 minutes ago, Frosty. said:

Lovely weekend coming up, dry and mainly sunny across most of the uk under high pressure, the fine weather continues into next week..nice ukmo 00z.

The GFS shows a lot of cloud across the UK Saturday and Sunday. 

The UKM to me shows a breeze coming of the north sea that s still cold and will bring with it low cloud and as the sun is still gaining strength it will struggle to burn of the low cloud and mist.

Positive charts, but a realistic appraisal is better.

I would add the west of the UK would do a lot better than the east in that setup

Edited March 22, 2017 by frosty ground

[Frosty.]

26 minutes ago, frosty ground said:

Positive charts, but a realistic appraisal is better.

 

Realistic appraisal..ok, the met office say the weekend will be dry and mainly sunny!

[frosty ground]

GFS once agains shows lots of cloud coming around the high, only really clearing on Monday.

[jvenge]

GEFS 06z largely in agreement out to T174 or so. In later frames GEFS then go onto showing colder air penetrating Scandinavia and into Central Europe. The UK is being quite lucky and is escaping colder air. I am as well :-D 

 

 

[Methuselah]

6 minutes ago, jvenge said:

GEFS 06z largely in agreement out to T174 or so. In later frames GEFS then go onto showing colder air penetrating Scandinavia and into Central Europe. The UK is being quite lucky and is escaping colder air. I am as well :-D 

 

 

Let's hope we stay lucky, jvenge...We don't want an April like 1981!

[jvenge]

Just now, Ed Stone said:

Let's hope we stay lucky, jvenge...We don't want an April like 1981!

I think even the most hardcore of coldies won't be wishing for cold weather now :-)

For me, the spring search consists of either looking for exciting storms or trying to search out the gloriously sunny days :-) I'm spoiled in summer, with most days glorious. As such, my net weather activity will diminish, as there aren't so many unknowns.

[MP-R]

20 minutes ago, jvenge said:

GEFS 06z largely in agreement out to T174 or so. In later frames GEFS then go onto showing colder air penetrating Scandinavia and into Central Europe. The UK is being quite lucky and is escaping colder air. I am as well :-D 

 

 

Well I suppose having missed out on most of the deep cold throughout the winter from similar synoptics, it's only fair we get warmth while other luckier places throughout the winter hold on to chilly conditions hehe.

Having said that, I'm seeing more of a nagging easterly breeze across the south at least which will likely take the edge of temperatures here and perhaps aid in keeping more cloud in place. Midlands north though would be really rather pleasant.

[jvenge]

10 minutes ago, MP-R said:

Well I suppose having missed out on most of the deep cold throughout the winter from similar synoptics, it's only fair we get warmth while other luckier places throughout the winter hold on to chilly conditions hehe.

Having said that, I'm seeing more of a nagging easterly breeze across the south at least which will likely take the edge of temperatures here and perhaps aid in keeping more cloud in place. Midlands north though would be really rather pleasant.

Enjoying a nice 18 degrees here today and we had a good winter.

We also had a dry summer, autumn and winter though, as compared to average, so I suppose the country could do with some rain, which the GEFS seems to be looking to give towards the weekend and beyond.

At this stage people will seek to avoid an overnight frost, as most are starting to plant already. Luckily most here don't even know what GEFS is, otherwise they would be a little worried at the output at T210.

I hope the UK has a good Spring/Summer. You deserve it after your shoddy winter. 

[Frosty.]

The GEFS 6z mean is predominantly settled from friday onwards, just the odd unsettled blip around day 10, mainly affecting the northwest but really if you are a fine weather fan you are in luck because high pressure looks like remaining close to or over the uk, at least the southern half for the next few weeks..or more. There will be variations in surface conditions but we should all see our fair share of sunshine and pleasant daytime temps but with an on going risk of chilly nights although frosts only look slight and some nights will be milder.

Edited March 22, 2017 by Frosty.

[knocker]

Just a quick look at the 12 GFS.

The east/west pincer movement still apparent which reinforces the trough out west which pushes east but the HP hangs on there until late in the day when the Atlantic gets a foot in the door. But this period still needs sorting as its around then that perhaps we may see another little amplification surge

Edited March 22, 2017 by knocker

[Summer Sun]

It looks like a fairly pleasant weekend is on the way with light winds and temps responding by day to the sunshine the far south may be cooler if your exposed to the easterly wind at first this get's cut off by Monday with a SE'ly

[Frosty.]

The Gem 12z shows a fine anticyclonic spell from this weekend with pleasant sunny spells followed by chilly nights but then a little disturbance affects the south and later next week the atlantic breaks through but only briefly as high pressure starts to build in from the southwest by T+240.

Edited March 22, 2017 by Frosty.

[Frosty.]

The Ecm 12z shows a fine weekend nationwide with a strong anticyclone centred over the uk, into next week it stays largely settled but with day to day regional variations in surface conditions as the high slowly declines with the east and southeast holding on to the best conditions for longest but later next week the atlantic breaks through as per the Gem but looking at that day 10 chart, I think high pressure would soon begin to build in again.  

Edited March 22, 2017 by Frosty.

[Frosty.]

The GEFS 12z mean shows high pressure taking control in the days ahead with a good deal of very pleasant spring weather with sunny spells and light winds but with chilly nights where skies clear. Into the mid range there is a bit of a hiccup as the high declines and the atlantic fires up a little but longer term the azores high builds in across the south whereas the north of the uk remains more atlantic influenced.

Edited March 22, 2017 by Frosty.

[Frosty.]

Goodbye vile trough, hello high pressure and rising temperatures on the Gfs 18z..feeling much more like spring soon with temps into the low to mid teens celsius, especially next week when mid 60's F is possible!

Edited March 22, 2017 by Frosty.