Model Output Discussion 12z 01/06/13

[Frosty.]

Is all that rain coming up from France? In the past few years that seems to be where all the rain problems come from; when rain comes in off the Atlantic you know it's generally going to be of normal intensity, but the continental stuff just seems unpredictable and much more likely to be intense, leading to flash flooding.

It looks like it, from that expanding trough further south and pulsing northwestwards up the western side of the uk, it could turn into quite a stark west-east split next week.

[Frosty.]

The Ecm 00z ensemble mean shows a warm and settled start to next week with a ridge but during next week, the influence of the atlantic low grows, it continues warm for the south and east in particular and increasingly humid with an increase in shower activity, some heavy and thundery but with sunny spells.

[Frosty.]

The areas of low cloud are now breaking up and melting away with more and more blue sky, a lovely afternoon in store for most of the uk.

[Frosty.]

The Gefs 06z mean, just like the ecm 0z ens mean, shows a warm and settled start to next week but the influence of the atlantic low then increases as it slowly spreads east but remains out to the west, so after a generally fine first few days next week, there would be an increasing risk of heavy showers becoming more widespread as pressure slowly leaks away but remaining warm and humid, sunshine and heavy showers but also some persistent rain at times but then the most unsettled weather eventually becoming more restricted to far northwestern parts of the uk where it would also become cooler, gradually becoming drier across southern areas, this would be due to a slow pressure rise from the southwest as the azores/atlantic anticyclone begins to extend a ridge towards and across the south and then slowly further north, so a slow recovery after a more unsettled spell still appears to be the most likely outcome but still the uncertainty continues.

Edited June 6, 2013 by Frosty039

[Bristawl Si]

It's certainly encouraging though Frosty, that any less settled spell is looking like it COULD be short lived.

Would certainly put a spanner in the works of recent mid-range forecasts for the 2nd half of June and into July to be unsettled.

[Summer Sun]

It's certainly encouraging though Frosty, that any less settled spell is looking like it COULD be short lived.

Would certainly put a spanner in the works of recent mid-range forecasts for the 2nd half of June and into July to be unsettled.

 

The met office are now seeing signs that it may become less unsettled in some southern areas in the long range forecast so who knows the GFS ensemble may well be onto something

 

[Frosty.]

It's certainly encouraging though Frosty, that any less settled spell is looking like it COULD be short lived.Would certainly put a spanner in the works of recent mid-range forecasts for the 2nd half of June and into July to be unsettled.

It would be very encouraging if the ukmo 00z verified, with the low further west and better orientated and high pressure holding firm to the east, it would put a much nicer complexion on next week instead of a deteriorating story. 

[AWD]

Some consistency within last nights EC ens and this mornings latest EC ens for temperatures after the weekend to remain around average (as a nationwide sentiment without going into local nuances) or at times, slightly below average. The London ens;

And the Birmingham ens;

With the exception of a day or two midweek next week where some could see locally above average temps as the trough edges closer and pumps up some continental air, temperatures look like being around the high teens and low 20c's typically. This also supported by the latest Met Office outlook.

Rainfall looks rather more difficult to ascertain currently. There are more mixed messages within both NWP output and ensemble guidance as to how much rain will be felt across the country. I expect large variations between conditons in the west and conditons in the east next week. The London ens;

and the Birmingham ens;

both show rainfall scenario's increasing but not to any particularly worrying levels. Most of what falls from the sky across England and Wales looks to be in the form of convection rather than frontal rainfall. Ireland and Scotland more prone to frontal rainfall being closer to the trough.

As ever with shower activity, some places will see little whilst others could see quite a lot. Too early to be regionally specific currently. There should still be some pleasent sunny spells inbetween shower activity across England, if not overly warm.

How long the more changeable conditons will last? Too early to say. It will take a lot more than NWP FI Operational output to determine that. Watch out for the behaviour of the Jet Stream, positioning of heights and the influence of the Azores HP to our SW. These will be influential to our weather patterns over the coming weeks.

[mushymanrob]

Is that based on science or just a hunch? Long range forecasting is mere guesswork anyway but, for what it's worth, the CFS has a warm July and ECM shows the current fine conditions largely rolling on for the south.

 

not sure what you mean sir.... i was saying you cant scrub the idea of another 07 (wet after an initial nice first week), no science or hunch, just common sense.... what the rest of the summer holds for us is far from clear and imho we can get anything from a drought to a washout.... apparently though the signals atm wouldnt point to a drought/sunshine/warmth. .... but no ones ruling that out either!

[weatherguru14]

why?

 

i personally dont expect anything like last year or 07, but theres no reason why another washout summer cannot evolve after a nice start like 07. i for one wont be scrubbing those chances, as has been said - the background signals are not very promising atm for a warm, sunny, dry summer.

2007  in my opinion was  a worse than  last summer for rain.June will turn out to be average to good.  We'd need a  really  bad July and August to be anywhere near last year never mind  2007. July and  August   you will get some  good weeks in there..Models change  like the  "wind".. 2007 was  atrocious and a once off. This forum is here to discuss  models.. From reading through them.The beginning of June   some members were  equating the model outputs to  summers of 03 and 06.. and nearly 2 weeks of good weather.. Members are looking at the  Models and  now mentioning 2007.. Its either wonderful and marvelous or horrendous  and  despair..

[johnholmes]

for what it is worth, in my view quite a lot as all 3 are showing very similar ideas for at least 2-3 days when one looks closely at their output.

This morning from ECMWF-GFS link is below and below that my comments this morning.

http://www.meteo.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

Thur 6 june

Ec-gfs

All 3 are really pretty similar with suggestions of some kind of +/ridging ne of uk but really near enough to have much effect(gfs being the closest) and the main player being the trough/upper low/-ve heights largely w of uk giving a rather unsettled look to the 6-15 day period; again all 3 have a mainly wly atlantic flow with its source from even further north not south so average temperatures to somewhat below and unsettled seems the most likely again in the 6-15 day time scale.

Edited June 6, 2013 by johnholmes

[NeilN]

17-20c does me good. Plus we do need the rain, so I'm happy with that. Hope it gets hot again at the end of June/July.

[Frosty.]

The Gfs 12z op run is looking fine, sunny and warm out to the middle of next week, at least for the eastern side of the uk but turning more unsettled across the west of the uk, even with the rain in the west it still looks rather warm and most likely humid with a southerly airflow.

Edited June 6, 2013 by Frosty039

[Frosty.]

The Gfs 12z brings an intense thundery breakdown with torrential rain later next week but before then, the eastern half of the uk in particular would be generally fine, sunny and very warm and increasingly humid, once the thunder and humid air clears, the gfs brings a short unsettled and less warm spell but further on, the azores/atlantic anticyclone again builds northeastwards and brings another fine and very warm spell not long after mid month, later in the month would also be warm and generally settled, a very good 12z but with some brief unsettled/thundery interruptions.

[NeilN]

If this happens, this looks VERY promising. We were discussing Summer 2004 and I think this os similar.

[Costa Del Fal]

I must say, it does feel like there are much stronger heights willing to go across Europe and the UK thus far. In previous years any high pressure ridges have been weak but some strong red colours on the charts. The CFS recently has been very keen on hot/high pressure weather for July. Interesting times ahead with an Atlantic breakdown next week being watered down/put back however some showers/rain next week is very likely.

[Frosty.]

If this happens, this looks VERY promising. We were discussing Summer 2004 and I think this os similar.

I like how the warm spell is being prolonged to midweek or later and the breakdown, when it does come, could be spectacular with all the warm/humid air across the uk. There are good signs for warm and dry weather to come back after an unsettled blip.

[Milhouse]

The GFS and UKMO both have high pressure holding firm over the eastern half of the UK on into the start of next week. Low pressure is expected to give us glancing blows but with winds from the SW it should remain warm throughout. Perfect synoptics which, given a tweak, could lead to a Spanish Plume.

 

The charts are reminding me of June 2003 with low pressure close by but just brushing the UK with frequent ridging of the Azores high. I wonder if the rest of Summer could match 2003 as well.

[Milhouse]

For eastern parts our time will finally come to see some summery temperatures from Monday onwards as the onshore easterly wind dies down.

 

[Frosty.]

The ukmo 12z shows high pressure in control until early next week, east is best on this run as by early next week it would be turning more unsettled in the west but as with the gfs 12z, eastern areas would hold on to the dry, sunny and warm weather for longest, by midweek though the high gets shunted to the east of the uk and it becomes generally unsettled for all areas with heavy thundery rain which would probably be followed by sunshine and showers and breezier, fresher conditions with temperatures falling back towards average.

Edited June 6, 2013 by Frosty039

[Milhouse]

Low pressure having a hard time on the latest GEFS mean. The mean position of the trough starts to the west of the UK before transferring north towards next weekend.

 

Edited June 6, 2013 by Milhouse

[Summer Sun]

ECM shows the low struggling to break through remains warm for all

 

[Milhouse]

Wednesday sees a band of rain crossing from west to east but the main energy is out in the Atlantic and unlikely to head our way.

 

[Summer Sun]

After the low tries but fails to breakthough next Wednesday we see the high rebuilding on Thursday pushing it back west again

 

Edited June 6, 2013 by Summer Sun

[Milhouse]

After the low tries but fails to breakthough next Wednesday we see the high rebuilding on Thursday pushing it back west again

 

 

 

Cool uppers at first but so much potential from that chart. I wouldnt be suprised if T+240 showed something very warm.

Getting there. One more frame and the very warm air would be over us.