Model Output Discussion

[johnholmes]

over what time scales OP, and can you provide a link to the site that shows this?

many thanks

[Ben_Cambs]

What I found from the NOAA website, the 6 day anomaly correlations from the models regarding 500hpa heights:

Then this historical chart, for the past 20 years: http://www.emc.ncep....ml/aczhist.html

The three main models performance has been very close over the past 20 years, but it does seem at times ECM and UKMO perform better than GFS in the long term.

Edited April 15, 2010 by Snowman0697

[johnholmes]

Yes thanks for that, I regularly look at and quote both the 5 and 6 day outputs on that site. What I was asking was for some information on the comments OP made about UK Met being in the lead, and over what time scale, as that site does not show that over the 5 or 6 day time scale.

Edited April 15, 2010 by johnholmes

[Thundery wintry showers]

I agree, the stats don't bear out the notion that UKMO has been best-performing- but on the other hand it's striking how UKMO has moved into a clear second place after the ECM, whereas until a couple of years ago it was roughly equal with the GFS. I'm guessing that the Met Office must have been working on closing the gap to ECM with their model's 4-6 day forecasting and it seems to be paying dividends.

[Eugene]

Looks like some notable air frosts likely on friday, sunday and monday night, down to -5C in parts.

Edited April 15, 2010 by Eugene

[BLAST FROM THE PAST]

For those tentatively mentioning summer warmth, I think the models will show a very warm spell more and more for the last week of April into early May....a beauty of a BH to come.

BFTP

[Eugene]

http://www.meteociel.fr/ukmo/run/UN144-21.GIF?15-18

Corking looking UKMO 12Z if it was winter of course

[Frosty.]

For those tentatively mentioning summer warmth, I think the models will show a very warm spell more and more for the last week of April into early May....a beauty of a BH to come.

BFTP

Any ideas for next winter yet fred :lol: hoping for another wintry one with minimum sun spot activity.

GFS 12z is looking like a warm up in FI with the cold snap early next week becoming downgraded with every gfs run, shows hp in control with sunny days and a touch of overnight frost with some mist followed by warmer winds from a southerly source.

[Mole]

Any ideas for next winter yet fred hoping for another wintry one with minimum sun spot activity.

GFS 12z is looking like a warm up in FI with the cold snap early next week becoming downgraded with every gfs run, shows hp in control with sunny days and a touch of overnight frost with some mist followed by warmer winds from a southerly source.

Now we have the uk 12 met model going for a wintry blast ,and its been against this idea for the past few days,the ecm is also in favor,and surprise surprise the12 gfs backtracks,it seems we can never get cross model agreement-what a joke these models are sometimes.

[BlueHedgehog074]

I think the GFS, with its 18Z update, have slightly upgraded the cold with cold/cool temperatures being fairly widespread on Monday, although the South and East should still have a chance of reaching double figures. Some very cold 850 hpa temperatures for the North on Sunday (varying from minus seven to minus ten), but the Northerly winds should help to bring some cold 850 hpa upper temperatures down South, and again, these could be quite widespread on Monday. A continued risk of some Wintry precipitation for the North, with lower ground prehaps just missing out on the Wintry weather.

A more of a warmer Springy feel after Monday, with the winds changing direction and bringing in some milder temperatures.

[Frosty.]

Now we have the uk 12 met model going for a wintry blast ,and its been against this idea for the past few days,the ecm is also in favor,and surprise surprise the12 gfs backtracks,it seems we can never get cross model agreement-what a joke these models are sometimes.

And now the GFS 00z has upgraded the cold snap for scotland again, especially for the northeast during early next week as a small low zips southeast from iceland but for most of the uk next week looks fine with high pressure in control and some overnight frost before it turns warmer in around a weeks time. I havent checked the other models yet but I think it's safe to say it will turn colder by sunday with wintry showers in NE Britain.

[Milhouse]

Still a very dry outlook for all but the north of Scotland with high pressure remaining in control. Signs are that we may pick up more of a southwesterly at the end of next week with the chance of some more unsettled conditions but the ecm keeps it mostly dry throughout.

[SP1986]

It seems the milder/warmer spell has been moved back, I was always dubious of this anyway I cannot see anything other than a cool, settled picture with potential frost right through until May.

[Milhouse]

The GFS 0z does show a transition to warmer yet more unsettled around the 23rd with still a week of the month to go and if my memory serves me right has consistently done so for a few days. The actual change may vary by a day of two but i think its a stroung enough signal for a warmer final week. Tomorrow isnt looking especially cool either with temperatures reaching 17c

[mushymanrob]

a great run for warm lovers in the gfs 06z fi... whilst it may have downgraded the immediate pressure rise after sundays cold front the gfs is still insistant that pressure will rise as next week goes on, with the centre drifting into the continent allowing the atlantic back in briefly before high pressure on the continent asserts itself. that would produce plenty of dry, war, sunny weather!

however thats mainly in fi, so im not holding my breath!

[Frosty.]

Latest models show a great run for cold lovers in the north, at least for a while although it does trend milder after the middle of next week with the north of scotland being the last place to see a significant rise in temperature, some snow showers are likely in NE Scotland on sat night and sunday with rain/sleet & wet snow on monday and snow showers for tues/wed but for the majority of the BI it looks less cold but still with some overnight frost but with plenty of sunshine and just a few showers and FI does promise a warm up but not necessarily a prolonged settled spell, could be more rain later.

Edited April 16, 2010 by Frosty039

[Derp Patrol]

This weekend looks like being a cool affair in Scotland, but further south into England and especially southern England it should stay pretty mild with plenty of sunshine. The BBC are showing 15-18C on both days this weekend in my area for example with lots of sunshine. I think that after this a warmer spell is pretty much nailed on, the runs in the past few days have suggested a plume in about a week, when we could finally see some real warmth.

[Milhouse]

Still looking good in about a weeks time and once again it coincides with the weekend.

20c quite widely achievable judging by this:

http://www.wetterzentrale.de/wz/pics/Recm2161.gif

[ANYWEATHER]

Ecm AND GFS sooooo different at t168...take your pick...!

[Nick F]

Ecm AND GFS sooooo different at t168...take your pick...!

ECM just looks slower with moving the waves (troughs/ridges) NE in the upper flow to me. 12z GFS often tends on the progressive side.

[damianslaw]

The reliable timeframe i.e. out to the middle of next week, a northerly airstream desparately wants to take control of the whole country. However, it is only really going to affect Scotland and far north of england due to high pressure being too close to the west of the country preventing a full on attack. Cold for Scotland especially the north east with wintry showers. Pleasant and mild for most of england and wales away from far north. Cold nights for all, noticeably cold which will prevent the CET from climbing.

Longer term, signs of the atlantic making inroads but all along way off, wouldn't be surprised to see the month end on a very unsettled cyclonic note, don't see the jet stream moving north anytime soon, meaning low pressure will most likely anchor itself over the country rather than to the north west.

[SP1986]

I knew it would continue towards May, GFS pumping out endless fantasies suggesting -6C and -7C covering most of Southern England on this run. Even tonights predictions of -3 and -4C seem like they will be way off. This is quite a big error considering there are no variables to overcome!

Still I do think a warm spell will not occur, I do think the GFS probably has this correct in the sense that the warm spell keeps being pushed back. So all in all a continuation of the cool weather with sunshine by day and perhaps a little ground frost by night for most.

[Eugene]

The good news is colder air delayed until monday bad news is a prolonged arctic northerly spell with a greenland high southerly tracking jet setup on GFS 18Z, at least the weekend looks warm by day anyway but next week has the potential for air frost almost anywhere every night esp northern UK which for late April is very unusual indeed, could record more air frosts next week than the last month.

Edited April 16, 2010 by Eugene

[SP1986]

Air frost is probably fairly normal in April, in these types of setups, just not the extreme rubbish that the GFS constantly comes up with.

I think we can be fairly confident that there is no chance of a warm spell (warm airmass) at the moment, and it looks like cold air will rule perhaps through until or into May.

It's probably going to be one of those frustrating type summers at this rate, where the patterns doesn't really suit anyones taste where it's not warm enough to be comfortable, nor cold enough to raise some question marks.

[Eugene]

http://www.wetterzentrale.de/pics/brack4.gif - Wintry showers moving southwards.

Strange comments on TWO saying the cold plunge has gone to our east, looks dead set for the UK to me with the 528 dam line moving southwards dwon the spine of the mainland and will probably sit through the midlands giving some very cold nights with light winds.