Model Output Discussion 12z 03/04/13

[Frosty.]

The Gfs 06z op run is EPIC if you love very warm anticyclonic weather, it just gets better and better during next week with continental heat building as high presssure builds to the southeast and some of that warmth drifting north into the southern half of the uk, temps would reach 25-26c later next week and generally 22-24c, maybe even breaking the 80f barrier in parts of the south and east. It's only the far north and west which would be dull, cool and wet but most of the uk basking in glorious late april sunshine with just the chance of an isolated shower breaking out in the heat of the day, chiefly for northern hills but many areas having either hazy sunshine with some high cirrus clouds or wall to wall clear blue skies. The 6z persists with the anticyclonic pattern throughout the run with just the occasional brief interruption although it does tend to cool off beyond next week.

[IDO]

Yes the 06z GFS run is very warm but a major outlier (London):

Though the second one in 24 hours, so maybe a trend (hopefully), yesterdays 12z:

ECM ensembles not as keen as the GFS (0z run) for as warm a week next week (London):

Added to that, the mean temps from D10-15 are rather cool, 2-3c below average. There is also a distinct trend amongst its members for an increase in rainfall totals:

So watching brief before us southerners get the deck chairs out!

Edited April 18, 2013 by i'm dreaming of...

[Frosty.]

The latest Ecm 00z ensemble mean and Gefs 06z mean charts are looking rather cold and very unsettled at T+240 hours, especially the ecm which also showed a wintry feeling end to the operational run, the thing to note about the mean charts next week is they keep the jet running wnw/ese with predominantly wnw'ly winds compared to some of the op runs today which have the jet aligned sw/ne with a good strong rise in pressure to the southeast, the mean shows the large atlantic/azores high being centred well to the southwest/west of the uk with a ridge extending southeast across southern britain with the north of the uk more unsettled throughout. If the mean charts verify in the 8-10 day period, we would see a return of snow showers to the scottish mountains and hills further south with frost risk increasing again so it might be best to make the most of the settled and rather warmer weather across the south of the uk next week.

Edited April 18, 2013 by Frosty039

[phil nw.]

The latest Ecm 00z ensemble mean and Gefs 06z mean charts are looking rather cold and very unsettled at T+240 hours, especially the ecm which also showed a wintry feeling end to the operational run, the thing to note about the mean charts next week is they keep the jet running wnw/ese with predominantly wnw'ly winds compared to some of the op runs today which have the jet aligned sw/ne with a good strong rise in pressure to the southeast, the mean shows the large atlantic/azores high being centred well to the southwest/west of the uk with a ridge extending southeast across southern britain with the north of the uk more unsettled throughout. If the mean charts verify in the 8-10 day period, we would see a return of snow showers to the scottish mountains and hills further south with frost risk increasing again so it might be best to make the most of the settled and rather warmer weather across the south of the uk next week.

Yes that GFS 06Z was a lovely Op run Frosty but it does look out of kilter further on.

The cooler and more unsettled end to April still looks likely looking at the ECM and NAEF`s pressure Anomalies at T240hrs.

Winds more north westerly as pressure falls with that high moving out into the Atlantic.

Very much underlining the Ens graphs posted above(post 727)-ie.a step up in precipitation and a fall off in temperatures.

However next week looks quite good with the centre of the high close to S.England for a time later next week so becoming sunny and warm for many of us i would think.

[Summer Sun]

GFS 12z is following the 06z run so far to t144

 

 

UKMO doesn't look bad either

 

 

[Milhouse]

GFS 12z very similar to the 6z out to 162h with low pressure in a similar position over Iceland and a southery once again developing. Uppers cooler though so it wouldnt be as warm to end the week as the 6z showed.

A very pleasant Thursday next week

 

[Paul]

Latest weekly outlook from Michael Fish 

 

[Summer Sun]

GFS continues to follow the 06z run out to t216 and we have the high rebuilding after leaving for a short period

 

 

Michale Fish above Ding dong the best from the east is Dead

Edited April 18, 2013 by Gavin.

[Milhouse]

I'd like to know where Michael Fish gets his pressure charts from because they do seem to go along with what the GFS 6z showed with a more extensive warm up next week. UKMO has low pressure over the Azores pushing warmth northwards and an expanding area of high pressure over Europe.

[Frosty.]

No sign of anything cold and unsettled on the Gfs 12z operational, it just follows on from the 00z and 6z with an increasingly warm and settled spell across most of the uk next week, cooler and more changeable across the far northwest corner but fine at times. Further into FI, pressure falls but the temperatures don't fall much, the ukmo 12z is looking very nice at T+144

 

This run is nothing like the latest met office update describes, it's also nothing like the ens mean for next week either.

Edited April 18, 2013 by Frosty039

[Milhouse]

No sign of anything cold and unsettled on the Gfs 12z operational, it just follows on from the 00z and 6z with an increasingly warm and settled spell across the southern half of the uk next week, cooler and more changeable further to the north/nw but fine at times. Further into FI, pressure falls but the temperatures don't fall much, the ukmo 12z is looking very nice at T+144

 

This run is nothing like the latest met office update describes, it's also nothing like the ens mean for next week either.

 

 

The key thing for me on the UKMO is that low pressure over the Azores holding the mid Atlantic high back and instead feeding in warm continental air over the UK. The GFS has low pressure over the Azores linking with low pressure over Iceland later on next week with the UK crucially on the right side of this to see a continuation of the warmth.

 

[SP1986]

The GFS is like a dog with a bone at the moment, it just wont let go of the outlook it shows... eventually it will have to back down and join the other model concensus, but we've seen the GFS do this before, stick with an output for a few days before reverting back to what the other models show. It's nothing if not consistent (and often incorrect in such circumstances!). So cooling down and becoming unsettled is still likely, but between now and then, plenty of useable weather with high pressure ridging in for a short time bringing a warm settled blip.. thereafter a slow breakdown from the west/northwest, and presumably continuing that way.

[Costa Del Fal]

The GFS is like a dog with a bone at the moment, it just wont let go of the outlook it shows... eventually it will have to back down and join the other model concensus, but we've seen the GFS do this before, stick with an output for a few days before reverting back to what the other models show. It's nothing if not consistent (and often incorrect in such circumstances!). So cooling down and becoming unsettled is still likely, but between now and then, plenty of useable weather with high pressure ridging in for a short time bringing a warm settled blip.. thereafter a slow breakdown from the west/northwest, and presumably continuing that way.

I've asked you this before. Examples with this scenario where the gfs has been like this? I'm not saying its right here but I don't get why it should be so wholly discarded? Is it so absurd to have more than 3 fine days. This time of year is when the Atlantic is at it's quietest and thus high pressure will hold on best. Again I'm not saying the gfs is right but you seem to be totally dismissing it. Risky in my opinion. I'd love more reasoning/examples behind your thinking.

[Cloud 10]

The GFS 12z was pretty much a mild outlier just like the 06z before it,with the

ensemble mean probably giving a more realistic view of what can be expected as

we head for the end of the month.

12z op run.. 12z ens mean..

[Summer Sun]

ECM is following on from this morning pretty much with the high slowly pushing northwards again during next week

 

[SP1986]

I've asked you this before. Examples with this scenario where the gfs has been like this? I'm not saying its right here but I don't get why it should be so wholly discarded? Is it so absurd to have more than 3 fine days. This time of year is when the Atlantic is at it's quietest and thus high pressure will hold on best. Again I'm not saying the gfs is right but you seem to be totally dismissing it. Risky in my opinion. I'd love more reasoning/examples behind your thinking.

 

I am totally dismissing it... in early March I recall when the GFS showed a move away from the cold spell, only to change and go with the ECM to prolong the cold. I'm sure people can give charts that show the same thing. I have not saved any charts that show this, but I do remember a few instances when the GFS has hung onto a specific outlook, only to move back towards the ECM. I couldn't name dates but it's definitely occurred. Let's just see what happens in the next few days.. the GFS and ECM are at consistent loggerheads after a certain point in the timeframe..

[Summer Sun]

GFS and ECM continue to do battle tonight at t192 with both taking a completely different route

 

[Frosty.]

High pressure and warm sunshine dominating next week across the southern half of the uk according to the Ecm 12z operational, more unsettled and cooler further north, so that is good news to go with the gfs 12z and ukmo 12z with a warm settled spell highly likely with temps into the 70's.

[Summer Sun]

High pressure and warm sunshine dominating next week across the southern half of the uk according to the Ecm 12z operational, more unsettled and cooler further north, so that is good news to go with the gfs 12z and ukmo 12z with a warm settled spell highly likely with temps into the 70's.

 

Yes looking nice upto Thursday (GFS was a milder outlier again so I'd expect temps around the mid teens which is very respectable for April) but it goes down hill just in time for the weekend (now there's a surprise......... not) as we await the next area of high pressure to try and push in from the west

 

Edited April 18, 2013 by Gavin.

[weather_it_will]

later on next week with the UK crucially on the right side of this to see a continuation of the warmth.

GFS 12z was a mild outlier, so later next week it will cool down, and will not be as mild as the operational 12z is showing.

Average temps around 8°C, so it will not be feeling very warm.

ECM also shows the cooling down later next week.

[Frosty.]

GFS 12z was a mild outlier, so later next week it will cool down, and will not be as mild as the operational 12z is showing.

Average temps around 8°C, so it will not be feeling very warm.

ECM also shows the cooling down later next week.

so you are just ignoring the warm settled weather which is shown on all the models for next week?

[Summer Sun]

so you are just ignoring the warm settled weather which is shown on all the models for next week?

 

And folk need to remember the uppers don't tell the whole story this time of year I remember a few weeks back when the uppers were widely -4 to -6c yet many parts of the UK got double figures the strong sunshine has a big effect now

[Milhouse]

Uppers were below 0c for most today and Humberside Airport still reached 16c which is above average for April.

 

ECM fine for next week up until Thursday then cooler showery conditions descending down from the north.

[Frosty.]

Gem 12z also looking very settled & warm and potentially very warm later next week with continental heat heading towards the south/southeast.

[Mr Frost]

so you are just ignoring the warm settled weather which is shown on all the models for next week?

Frosty if anywhere in the UK gets into the 70's next week as you suggested I will eat my socks.

The only parts of the UK which will see any decent temps are the South and East of England next week. Even this weekend with plenty of fine weather about (Saturday mostly) the North is looking at 12 degrees max and the South 15 degrees max. Hardly anything to get excited about in normal circumstances. (The long run of cold months has everyone chasing a sniff of warmer weather)

The ECM has this nailed, cooler and unsettled is the way ahead.

The ens mean for the beloved GFS in here shows it.

I enjoy reading what you post but I think the orange and reds on the maps are CLOUDING your judgement.

More HIGHS and LOWS to come in this thread over the next month I feel, SUN would say we are DEW a early heatwave. But as you know it never rains but it pours when we wish for something different.

Have you read the recent Met Office outlook?

UK Outlook for Tuesday 23 Apr 2013 to Thursday 2 May 2013:

Largely unsettled with showers or longer spells of rain across the UK. Initially the rain will be heaviest and most persistent across the north and west, and showers may turn wintry at times across northwestern hills. The south and east of the country will see the best of the dry and bright weather with some spells of sunshine. At first temperatures will generally be near or just below normal across the north and west but perhaps rather warm in brighter interludes in the south and east. Later next week and into the following week, the unsettled weather in the northwest will probably spread southeast to all parts. Temperatures will become rather cold or cold in all areas with overnight frosts probably becoming more widespread.