Model Output Discussion 14th May 2012 Onwards

[Evening thunder]

I think there have been a couple runs recently that have hinted at something like the ECM shows. The change isn't right at the end of the run either, as soon as I saw the T+144 chart with the high retrogressing west with that low popping up NE of Iceland I thought I know where this is going.. Then confirmed by the T+168 chart. The GEM also shows a slightly cooler 850hpa pool moving in from the east with an undercutting low, so maybe not warm and settled this weekend or after that everywhere.

As other models and ensembles I've seen so far don't show this, then it makes me think this is less likely to happen, but the ECM's evolution wouldn't surprise me either.

Still whatever happens, it's pretty far away and we have 4-5 days of settled and warm-very warm (away from some areas near the east coast) weather to come before any possible change.

[ANYWEATHER]

12z Gfs is on its own. im afraid! Its outputs previously along with the ensembles show a steady decline in pressure from the South during this weekend along with the Metoffice view and along with the current 12z ecm output! Anyway, here some charts to highlight my point, from gfs and ecm....

[J10]

The disagreement after this weekend shows that nothing is nailed on for next week. Even though there were hints last week, that this week would turn pout quite good, the high temps were only really forecasted at very short notice.

[Summer Sun]

Ensembles remain pretty dry for the north for a good while yet,

Slightly wetter for the south

[IanR]

That last chart is more my bag.......a nice little thundery low drifting up from the south......niiiiiice

Yes , I want that too,

Perfect summer for me... lots of warm sunny weather but frequent interruptions from thundery lows from the south, just to stop any tedium,. if only we could have that pattern till late september,' sigh'

[Glacier Point]

12z Gfs is on its own. im afraid! Its outputs previously along with the ensembles show a steady decline in pressure from the South during this weekend along with the Metoffice view and along with the current 12z ecm output! Anyway, here some charts to highlight my point, from gfs and ecm....

Disagree here, the op ECM is odd man out IMO.

GFS ensemble mean, CPC 8-14 dayer, ECM ensemble mean all suggest a high pressure outlook.

[johnholmes]

I'm not sure those wanting to dismiss the ECMWF output are doing so as hopecasting for a continuation of a dry warm settled spell or not.

I would be very wary of dismissing ECMWF it has a far better record (for the northern hemisphere) at 500mb than GFS has-see the stats on the 6 day outputs as some indication although that does not necessarily mean GFS is as far behind at 10 days. I have no stats to prove things one way or the other.

The ECMWF 10 day 500mb output this morning and the NOAA 8-14 day issue this evening are rather similar with taking the main upper ridge NW of the UK-fairly different from what was showing 2-3 days ago, even 1 day ago. GFS does not. I would want to see another couple of outputs before I went for one or the other for 10 days hence from today.

Edited May 21, 2012 by johnholmes

[Alex]

Disagree here, the op ECM is odd man out IMO.

GFS ensemble mean, CPC 8-14 dayer, ECM ensemble mean all suggest a high pressure outlook.

You and John - couldn't be more different in your views tonight, however I tend to agree with the GFS option tonight especially as the MJO seems to be stIcking within the phases of 7/8. Where do you think we go from here though Stewart, can we continue a settled spell into the bank holiday and into June?

Edited May 21, 2012 by Alex

[Thundery wintry showers]

I think the ECMWF operational is the odd one out here but it has been very consistent in showing retrogression of the high towards Greenland allowing Arctic air to head south. Tthe northerly shown at T+216-240 on tonight's ECM run would be unusually cold for the end of May and is almost certainly being overblown, but I don't think it can safely be dismissed when it has shown this much consistency.

The ECMWF ensembles haven't yet shown much support for the operational runs, but nor do they really support the stronger high pressure shown by GFS/UKMO, instead going along with the earlier UKMO/GFS consensus of the high holding on in the north and lower pressure becoming prominent to the S and SW promoting a stronger easterly airflow. This would promote increased chances of showery rain towards the SW, while keeping generally quiet weather in the northern two-thirds of the country but potentially cooler/cloudier in the east, particularly if we pick up airmasses from north of due east. The UKMO/GFS scenario would probably be sunny and warm away from eastern coastal areas.

It's pretty tough to forecast at the moment but if I had to stick my neck out I'd stick with what the ECMWF ensembles are showing and suggest that GFS/UKMO might have over-reacted to a signal somewhere. It will be interesting, though, to see if the ECMWF operational runs are onto something with their retrogression scenario.

[Alex]

ECM delays the retrogression of our ridge to Greenland on the latest 00z which indicates to me that nothing is set yet for next week esp as the GFS keeps the settled weather going with the anticyclone traveling south and settling near or over us!

[samadamsuk]

morning all.

Certainly a different situation to the last 8 weeks! Cold air being drained off over the top of the high into russia, and the western atlantic trough being maintained, but not progressing east, and a succession of lows that disconnect from the trough and sit out to our west helping to keep waa in place and the high pumped up. http://www.met.sjsu.edu/weather/models/gfsp/thick-ani.html

imo looks promissing for June at the moment -

Cheers, Sam

[Summer Sun]

GFS continues to have high pressure dominating well into next week, this looks like lasting a lot longer yet

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

UKMO

High pressure dominates its run into next week

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

ECM

High pressure dominates well into next week

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

This is here to stay for a while yet

[Backtrack]

GFS continues to have high pressure dominating well into next week, this looks like lasting a lot longer yet

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

UKMO

High pressure dominates its run into next week

http://www.jp2webdes....uk/ds/ukmo.htm

ECM

High pressure dominates well into next week

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

This is here to stay for a while yet

Met Office update reflects the sunny weather lasting into the new working week, but thereafter it turns unsettled in the south, but staying settled in the north.

Just shows they don't always follow their own model to reflect their updates, as they have clearly backed last night's ECM for this morning's update.

[shedhead]

Whatever way this ultimately pans out, I think most of us would have grabbed the current outlooks this time last week, so at the end of the day it's all relative. Single digit maxima seem a long time ago now, but in reality they were only last week, so lets just be grateful for this marked improvement - however long it lasts.

Edited May 22, 2012 by shedhead

[Thundery wintry showers]

The Met Office satellite imagery shows that the cloud spilling in off the North Sea fizzled out for most early this morning (including here in Tyneside) and so two dry, sunny, warm days look strongly odds-on during today and tomorow for the vast majority, the only significant exception being Ireland where fronts will be close by. Tomorrow highs of 20-23C will be widespread with 24-26C possible. Isolated sharp showers will develop over central and western areas on Wednesday but most places will stay dry. Probably a mix of broken cloud and sunny intervals for most on Thursday as some cloud spills in off the continent accompanied by isolated sharp showers in inland areas, and staying warm.

I think a cooler cloudier blip is likely in eastern areas on Friday/Saturday as we pick up a stronger easterly flow originating from north of due east, but a model consensus has developed that the easterly will slacken off again during Sunday and into early next week allowing warmer, sunnier conditions to take hold again. Remaining sunny and warm throughout in western Scotland and NW England.

[Deluxe]

Good summary of the short-term outlook TWS. Still rather uncertain what happens afterwards, but as others have said the likelihood of more unsettled conditions in the S and SW with northern areas staying mostly fine and dry looks the favoured option at present, with temperatures gradually returning to average, maybe a notch above

Edited May 22, 2012 by Hartle

[Robbie Garrett]

CFS is showing this week as averaging at 17-18*C, with max of 26*C in the forecast on 12th June and 21st. July is showing a fairly warm outlook, with temperatures like to be in the high 20s, to low 30s. End of July, there is a spike of 25*C for one week as an average mean max, I suspect this would mean temperatures would be about 34-35*C as a maximum.

With 27*C in the last week of July as a mean max, so chances are the UK record may go if it continues to outplay. The mean max calculates the maximum low temperature and maximum temperatures as far as I am aware, looking at this weeks temperatures and what the CFS has forecasted to get a mean. So 37-39*C by last week of July looks very much possible, with parts of spain hitting 41*C

As we get into August temperatures are likely to take a tumble, with low-to high 20s possible.

[Derp Patrol]

CFS is showing this week as averaging at 17-18*C, with max of 26*C in the forecast on 12th June and 21st. July is showing a fairly warm outlook, with temperatures like to be in the high 20s, to low 30s. End of July, there is a spike of 25*C for one week as an average mean max, I suspect this would mean temperatures would be about 34-35*C as a maximum.

With 27*C in the last week of July as a mean max, so chances are the UK record may go if it continues to outplay. The mean max calculates the maximum low temperature and maximum temperatures as far as I am aware, looking at this weeks temperatures and what the CFS has forecasted to get a mean. So 37-39*C by last week of July looks very much possible, with parts of spain hitting 41*C

As we get into August temperatures are likely to take a tumble, with low-to high 20s possible.

I have a feeling that this summer is going to be a great one.. and that would be perfect if this came off! Would be good for the Olympics as well

[ANYWEATHER]

CFS is showing this week as averaging at 17-18*C, with max of 26*C in the forecast on 12th June and 21st. July is showing a fairly warm outlook, with temperatures like to be in the high 20s, to low 30s. End of July, there is a spike of 25*C for one week as an average mean max, I suspect this would mean temperatures would be about 34-35*C as a maximum.

With 27*C in the last week of July as a mean max, so chances are the UK record may go if it continues to outplay. The mean max calculates the maximum low temperature and maximum temperatures as far as I am aware, looking at this weeks temperatures and what the CFS has forecasted to get a mean. So 37-39*C by last week of July looks very much possible, with parts of spain hitting 41*C

As we get into August temperatures are likely to take a tumble, with low-to high 20s possible.

Arrgh! Cfs is fairly good [At Times] at depicting trends but as regarding forecasting detail that far out, well you may as well predict whos going to win this Saturdays night winning Lotto winner!

[Robbie Garrett]

Arrgh! Cfs is fairly good [At Times] at depicting trends but as regarding forecasting detail that far out, well you may as well predict whos going to win this Saturdays night winning Lotto winner!

I have a feeling that this summer is going to be a great one.. and that would be perfect if this came off! Would be good for the Olympics as well

It is fairly good, but a lot of people are saying this Summer may be fairly good. Hottest temperatures since 2006 (maybe even 2003) may be possible, because of how the weather has panned out. Thank god for soggy April and May, aye?

As long as I get to see Wimbledons Womens tennis, I am happy....

Edited May 22, 2012 by Robbie Garrett

[Lewis]

Very nice weather out there today, I've never felt so good than today, amazing what some warm weather brings, i've been overly using the phrase "Doesn't feel like May" throughout the past 2 weeks, finally I can put it too bed and stop moaning about the darn weather.

Settled, humid and hot for many parts.

Interesting charts if your looking for storm potential, very high CAPE values for many areas throughout the course of the coming 3-4 days, mainly for areas inland, with eastern coastal areas/areas close to the coast having an on shore breeze, and a cap will also be in place.

What temperatures do you guys think we would need to hit for the CAP to be broken and so we can tap in to all of that energy?

Could be a lightning show for the South Coast on Friday night.

Lewis

Edited May 22, 2012 by UK Storm Chasers

[Summer Sun]

High pressure is shown to last well into next week for the north before a slow breakdown, a new area of pressure then build's just after the long bank holiday weekend

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

[Milhouse]

UKMO shows high pressure in charge but with low pressure close enough to deliver the threat of showers to the south west. For most areas its a continuation of the dry and warm conditions. Winds remaining easterly although showing signs of turning more southeasterly later.

http://www.wetterzen...cs/Rukm961.html

http://www.wetterzen...s/Rukm1201.html

http://www.wetterzen...s/Rukm1441.html

Edited May 22, 2012 by Milhouse

[Summer Sun]

High pressure just about dominates for all of ECM's run the only exception is the south west ealy next week other than than high pressure is here for a while yet, ends unsettled but thats ages away

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

Edited May 22, 2012 by Gavin D

[ANYWEATHER]

A slow change from the South as Pressure starts to fall away from the gfs and ecm and ukmo late weekend/earlynext week.....