Model Output Discussion 12z 03/04/13

[Frosty.]

The Gfs 00z is looking very anticyclonic from around T+168 onwards, really promising for northern and western areas after the unsettled 5-7 days ahead, next week it looks driest and warmest across the far south as pressure will be that bit higher down there but not fully escaping the unsettled weather, the north and west of the uk will bear the brunt of the poor weather though but the gfs 00z then brings a complete change from the end of next week with sunny days but frosty nights in the north for a short while before temps become higher by day and night.

[johnholmes]

Message for John (no pm possible still) Good morning!

 

You asked me to remind you about a London Marathon forecast so I'm taking the liberty of doing so! It would be fantastic if you could do one. The event is Sunday week, so 9 days off now and a number of runners have been asking the all-important question! Even if it's tentative to start with, and then updated would it be possible to do one?

 

Thank you so so much in advance.

hi

I will pm you if I can, not sure why you are not able to pm me.

[Frosty.]

Ecm 00z not as settled as the gfs 00z,  it still looks largely dry, fine and warmish across southern and eastern areas next week and briefly settled everywhere at the end of next week but the north and west mostly suffering under low pressure with only temporary respite.

[Purga]

Interesting update from:
 
Matthew Hugoâ€@MattHugo81

Latest EC32 potentially signalling more of a N or NW'ly flow by late April into early May with below average temperatures.

 

Seems to be indicated by GFS FI yesterdsay 12z but not so much today. ECM 0z today could be trending cooler however.

[Summer Sun]

The ECM ensemble continues to go for high pressure to build around next weekend

 

Edited April 12, 2013 by Gavin.

[Heisenberg]

Hi all, Sorry to post this in the mod thread but its kind of model related. Im going to centre parcs sherwood forest next week and wanted to ask the more lerned what i can expect weather wise?

GFS seems to be showing a mix of cloud with some rain....does this look acurate to you guys? Any help would be greatly appreciated.

[Frosty.]

Hi all, Sorry to post this in the mod thread but its kind of model related. Im going to centre parcs sherwood forest next week and wanted to ask the more lerned what i can expect weather wise?

GFS seems to be showing a mix of cloud with some rain....does this look acurate to you guys? Any help would be greatly appreciated.

Ecm looks better next week for most of the southern half of the uk or at least the southern third, with the warmest, driest and brightest weather to the south and east, so if the ecm was right, you should see some bright very mild weather but the gfs 00z is more unsettled for most of the BI next week.

Edited April 12, 2013 by Frosty039

[Frosty.]

It's good news if you like settled weather from the latest ensemble mean, both the GEFS 00z mean and the Ecm 00z ens mean are showing a gradual rise in pressure from the south and west as time goes on with a generally anticyclonic further outlook, nationwide. In the meantime, a generally unsettled pattern will dominate the north and west but rather higher pressure to the south and east with the best of the sunshine and the highest temps, sunday looks warm and bright towards the southeast with temps of 16-18c, maybe squeezing a 19 or 20c in a few favoured spots as the airmass will be tropical maritime so any sunshine will really boost the temps, but most western and northern areas will be duller and wetter with stronger winds and gales developing by late saturday and continuing on sunday but the south and east look better, next week strongly suggests a northwest-southeast split with the northwest most unsettled and the southeast only having small amounts of rain and a lot of very mild, dry and bright weather.

Edited April 12, 2013 by Frosty039

[No Balls Like Snow Balls]

Yes ECM 32 dayer shows well below average temps. Any snow would be restricted to only the highest of ground I think.

Still just because the ECM shows what it does doesn't mean to say it will be proven correct.

Edited April 12, 2013 by No balls like Snow Balls

[Methuselah]

I don't have that much faith in the ECM 32-dayer, I'm afraid. It just has about 27 days' of FI to enjoy... 

[Purga]

Yes ECM 32 dayer shows well below average temps. Any snow would be restricted to only the highest of ground I think.

Still just because the ECM shows what it does doesn't mean to say it will be proven correct.

It will be interesting to see what heed if any METO pay to the ECM 32 dayer in their further term updates today.

[Frosty.]

A very promising Gfs 06z op run, next week in particular looks much better than the gfs 0z with higher pressure for most of southern britain, it still looks changeable/unsettled for the north and west though but even those areas improving by the end of next week with high pressure building, a very anticyclonic outlook and trending warmer, then briefly cooler as the azores high and scandi high link up later in FI but as the european mainland warms up by late april, we also warm up again. So a very blocked high pressure dominated outlook from the 6z and this is also what the gefs and ecm mean are showing today.

[johnholmes]

I never attempt to predict much beyond the range of the scope of the 500mb anomaly charts along with keeping an eye on things like the MJO, actual and prediction, and the AO and NAO.

It really would be a great idea if someone could make a note, if they have access to the ECM32 day outlook, note each one and make a judgement as accurately as they can of its accuracy 32 days on or say in the range 20-30 days. That way we can have some proof of how accurate or not it actually is when taken in conjuction with other drivers?

No not me I have done a number of 1-3 years checks on various outputs over the years so someone else have a go?

Looking at the MJO, AO and NAO along with the anomaly charts there is nothing to me that really suggests any northerly outbreak in the 6-20 day time scale. If that changes I will post such in here and the other thread. There is some doubt on how the upper ridge will settle, whether it be a flattish type south of 50N or a more ridgy type and somewhere over or a shade S/SE of the UK. As GFS shows at times it may also be that the surface ridge ends up not SE but NE of the UK, too uncertain for me to be able to suggest which of these patterns will be the end result. Changes MAY cause this ridge to edge further west which may be what the ECM 32 day outlook is showing but without having routine access to it over several weeks it is impossible to know about that.

 

It will be interesting to see what heed if any METO pay to the ECM 32 dayer in their further term updates today.

remember also that UK Met have a whole series of other inputs as well as that to base their professional view on.

Edited April 12, 2013 by johnholmes

[Summer Sun]

It will be interesting to see what heed if any METO pay to the ECM 32 dayer in their further term updates today.

 

Non by the looks of it coastal areas could be cooler due to the cold seas but inland it will become warm at times still a chance of ground frost in any clear settled spells but other than that average temperatures are expected

 

[mushymanrob]

blimey, the soil is very dry!!!! just done some planting expecting it to be moist...but no...

 

and looking at the recent runs i dont think there will be much rain as pressure is expected to be on the high side.

 

got rid of the cold, can i moan about the cloud now? :lol:

[johnholmes]

Non by the looks of it coastal areas could be cooler due to the cold seas but inland it will become warm at times still a chance of ground frost in any clear settled spells but other than that average temperatures are expected

 

maybe not Gavin but their 30 day outlook as the number indicates finishes 2 days prior to the ECM 32 day although one would expect some indication would be showing in their overall assessment. It will depend to some extent on where in the 32 day the ECMWF suggests this cool down?

Hence my suggestion of caution in making assumptions from any of us when we do not have routine access to a model available to them and those with large bank accounts!

[Summer Sun]

maybe not Gavin but their 30 day outlook as the number indicates finishes 2 days prior to the ECM 32 day although one would expect some indication would be showing in their overall assessment. It will depend to some extent on where in the 32 day the ECMWF suggests this cool down?

Hence my suggestion of caution in making assumptions from any of us when we do not have routine access to a model available to them and those with large bank accounts!

 

This is the temperature max from it

 

 

This is the mean temperature

 

[Purga]

I don't think the 16-30 day period has updated yet - has it? This is where METO might factor in the EC 32 data - perhaps. As I said I'm not sure what weight they would put behind this output, just interested to see.

[Gael_Force]

FAO John Holmes.  - not able to receive pms apparently?

 

 

I note you mention interest in the accuracy/verification of the ECM mid range forecasts. Just wonder if you have seen my post with a link to the hindcast analysis that the ECM provide on their site.

http://www.ecmwf.int/products/forecasts/d/charts/mofc/verification/anomaly/

[phil nw.]

The jet is still shown to be running across the UK into next week with the attendant frontal systems crossing the country during the next 5 days.

The fax charts give a good indication of this- 2 examples here at different times.

so we have the warm up but still with some rain or showers about for a few days more so further NW away from those rising heights over the continent.

If these mean charts verify though it looks the end of the week sees high pressure extending further north

http://modeles.meteociel.fr/modeles/gens/run/gens-21-1-174.png?6

http://www.meteociel.fr/modeles/ecmwf/runs/2013041200/EDM1-192.GIF?12-12

looks quite promising for more widespread fine weather towards next week end.

[Frosty.]

There is a very good chance of reaching 20c in eastern england on sunday, maybe 21c 70f in the most lucky places but generally 16-18c, the west and north not as warm but mild enough at 12-15c but with gales and spells of rain, the south and east sunnier and generally dry on sunday. Next week the temperature maps clearly show the north-south divide starkly, the north of the uk much cooler with strong winds and outbreaks of rain, the south and southeast of the uk much milder and drier, brighter than the north but not as warm as sunday with temps close to 16c 61f rather than the mid 60's.

Edited April 12, 2013 by Frosty039

[mulzy]

Yes ECM 32 dayer shows well below average temps. Any snow would be restricted to only the highest of ground I think.

Still just because the ECM shows what it does doesn't mean to say it will be proven correct.

 

 

Just out of interest, where do you get these ensemble graphs from?

[Summer Sun]

Just out of interest, where do you get these ensemble graphs from?

 

http://www.weatherxchange.com/ensemble/display.php?site=Coleshill&type=15daytsE&element=Tmax&TST=Box

 

I don't think the 16-30 day period has updated yet - has it? This is where METO might factor in the EC 32 data - perhaps. As I said I'm not sure what weight they would put behind this output, just interested to see.

 

They've both updated http://forum.netweather.tv/topic/64157-meto-uk-further-outlook/page-60#entry2680162 & http://forum.netweather.tv/topic/75951-met-office-16-to-30-day-outlook/?p=2680163

[Frosty.]

I'm surprised and disappointed by the meto update because it continues to say it will remain generally unsettled to the north and west throughout the next few weeks when the latest gefs and ecm mean is showing pressure becoming high across all parts of the uk from T+168 onwards, so whilst I agree with the northwest-southeast split next week, i'm not sure that would also apply beyond the end of next week if the mean continues to show pressure rising from the south and the west, surely the jet and the lows would be steered well to the north of the uk if the current trend continues, the only fly in the ointment was the ecm 00z op run which showed unsettled weather soon returning to the north after a settled day or so.

[johnholmes]

FAO John Holmes.  - not able to receive pms apparently?

 

 

I note you mention interest in the accuracy/verification of the ECM mid range forecasts. Just wonder if you have seen my post with a link to the hindcast analysis that the ECM provide on their site.

http://www.ecmwf.int/products/forecasts/d/charts/mofc/verification/anomaly/

thanks GF I'll save that and have a look to see just what it is showing in terms of a check-thanks

again no idea why anyone cannot pm me, have asked Paul and he can see nothing, WIB has found he can pm me!