Model Output Discussion 1200 hrs 15/11/14

[DAVID SNOW]

When is the end of the run?  Now that is an interesting development isn't it?  I've been happy with this evenings output and this is further interest, expect more interesting runs and developments to show over next 7 days...

 

BFTP

 

MOGREPS Out to 15 days I think Fred.

 

As others have said

Edited November 19, 2014 by DAVID SNOW

[Ali1977]

Does this mean model watching is going to start getting exciting again....!! Let's see what the 18Z GFS brings, hopefully some FI eye candy. Do mogreps run daily?

[LomondSnowstorm]

Given the 'parts of Scotland' comment I'm assuming it's either an undercut where the low is a bit too far north to deliver for most of England but gives a decent easterly up here(mid February 2010/February 2001 type event) or a cold trough type setup where the low pressure is deflected southwards in situ but accompanied by Arctic air from the northwest (sort of like early December '76) or possibly, and this is maybe the outside bet given the current synoptics but still plausible given it's 15 days out, a north/northwesterly with a mid Atlantic ridge. Or none of these things  Interesting stuff anyway, although frankly it's still too far out to get really excited about, but would be nice to see the 'c' word, or maybe even the 's' word, in the MO long range outlook.

 

Certainly looks pretty far from standard Atlantic driven weather anyway, even if it isn't particularly cold yet - we've certainly seen how difficult it is to shift Russian highs over the years and having one in place this early is definitely a good sign for winter, whether or not we directly benefit from it in the next week or two.

[Summer Sun]

GFS ens's are in good agreement for a cool down as we enter December

 

 

You never know guys something maybe brewing for early December

 

 

 

  ?

[Chris K]

Does this mean model watching is going to start getting exciting again....!! Let's see what the 18Z GFS brings, hopefully some FI eye candy. Do mogreps run daily?

 

http://www.metoffice.gov.uk/research/modelling-systems/unified-model/weather-forecasting

 

The MOGREPS medium range ensemble runs twice daily, 0000 and 1200hrs.

 

Whilst nice to hear about it appearing at the end of the run in the latest update, I think it is still worth pointing out that at 15 days away, caution is required of it verifying (as I am sure everyone is fed up of hearing).

 

For the cold seekers, we would need to see these hints of favorable weather patterns start moving into a closer time frame and with cross-model agreement.

Edited November 19, 2014 by Chris K

[nick sussex]

Still quite a few different solutions from the ECM ensembles at T120hrs:

 

Theres some much better solutions than the operational run but also a few stinkers aswell:

 

 

You can see on the short De Bilt ensembles that the operational run especially in the middle is right at the top end, a lot more colder options:

 

http://www.knmi.nl/exp/pluim/Data/PLUIM_06260_NWT.png

Edited November 19, 2014 by nick sussex

[bluearmy]

MOGREPS is hinting and peeps are getting excited. What happens when MOGREPS indicates something cold??

my take would be that the Siberian vortex seems to be heading further east and that should allow the scandi ridging to be reinforced by the Siberian high rather than regenerating itself by WAA from the Atlantic striking the Russian high. all a bit pedantic to be referring to scandi/Russian/Siberian but the further east the source of the blocking, the stronger it will be. At the moment, the vortex residing in nw Siberia means the Siberian ridge is forced to push sw rather than west. the are other factors that appear to be coming into play which I think could also aid any block becoming more rigid. it could be time for the colder air to advect west.

[IDO]

The latest NOAA suggests more of a Scandi anomaly for D8-14 compared to the D6-10 anomaly, which is more a sceuro anomaly. Little steps:

 

 

 

 

[blizzard81]

Still quite a few different solutions from the ECM ensembles at T120hrs:

 

Theres some much better solutions than the operational run but also a few stinkers aswell:

 

120.gif

 

You can see on the short De Bilt ensembles that the operational run especially in the middle is right at the top end, a lot more colder options:

 

http://www.knmi.nl/exp/pluim/Data/PLUIM_06260_NWT.png

Crucially supported by the control run so the chances are it is on the money.

[blizzard81]

Massive spread on extended ECM ensembles tonight

 

[johnholmes]

Some good news from the MOGREPS:

@EssexWeather: Met Office ensemble (MOGREPS) hinting towards the end of the run that high pressure may end up in a favourable position for cold.

https://twitter.com/essexweather/status/535160974429671425

Scotland the initial beneficiary.

 

I wonder just what the MOGREPS actually showed in terms of where any high might be. Perhaps Ian will update us with a factual account.

In the meantime then the NOAA 6-10 and 8-14 continue, see below, with the pattern they have suggested over several days. Troughing into the UK and SE with +ve heights and ridging NE of this. It is not too different from how EC-GFS show the pattern. So in 2-3 days IF this is correct then some indications of surface positions of lows and highs should start to show on Met Fax charts. For new folks following these, yes wrong at times, is a less ulcer producing idea than the 4x GFS double outputs in my view. But if you enjoy the ride on you go.

[nick sussex]

Crucially supported by the control run so the chances are it is on the money.

I wouldn't bet it on it! lol It's been a weird week in the output with large swings and with the very quick re-amplification of the upstream pattern NWP can take a while to settle down. At this point nothing would surprise me.

[Cloud 10]

I wonder how well the MOGREPS verifies compared to the ECM ensembles?

 

 

Like groundhog day watching these scandi height anomalies.

 

[johnholmes]

Currently, on the 6-15 day 500mb charts there is little sign of this amplification?

I presume you refer to this Nick

EXTENDED FORECAST DISCUSSIONNWS WEATHER PREDICTION CENTER COLLEGE PARK MD1055 AM EST WED NOV 19 2014VALID 12Z SAT NOV 22 2014 - 12Z WED NOV 26 2014...OVERVIEW...THE LARGE SCALE PATTERN WILL RAPIDLY AMPLIFY DURING THE FIRST HALFOF THE PERIOD TO YIELD A DEEP CNTRL CONUS TROUGH THAT SHOULD DRIFTEWD NEXT MON-WED WHILE A MEAN RIDGE BUILDS TOWARD THE WEST COAST. ASIDE FROM SOME DETAILS THE LATEST MODEL/ENSEMBLE GUIDANCE INTODAY 6 TUE OFFERS REASONABLY GOOD CLUSTERING FOR THE STREAMINTERACTION LEADING TO A DEEP GRTLKS STORM AHEAD OF THE AMPLIFYINGTROUGH AS WELL AS FOR THE UPSTREAM RIDGE.  HOWEVER STARTING AROUNDTUE DIVERGENCE IN SOLNS ARISES DUE TO DIFFS IN FLOW SEPARATIONWITHIN AN ERN PAC TROUGH... ULTIMATELY IMPACTING THE FCST OVER THEWRN HALF OF THE CONUS BY DAY 7 WED.

The anomalous ridging and troughing NOAA talk of is just tha,t anomalous, in terms of long averages for this time in November but not in actual 500mb patterns.

Looking at the 500mb 6-10 and 8-14 I confess to not seeing where the first sentence above comes from. In another  issue those phrases are not there?

[Nouska]

I wonder just what the MOGREPS actually showed in terms of where any high might be. Perhaps Ian will update us with a factual account.

In the meantime then the NOAA 6-10 and 8-14 continue, see below, with the pattern they have suggested over several days. Troughing into the UK and SE with +ve heights and ridging NE of this. It is not too different from how EC-GFS show the pattern. So in 2-3 days IF this is correct then some indications of surface positions of lows and highs should start to show on Met Fax charts. For new folks following these, yes wrong at times, is a less ulcer producing idea than the 4x GFS double outputs in my view. But if you enjoy the ride on you go.

 

 John, you were mentioning the MJO phase in an earlier post - I did some checking last night after reading Mike Ventrice's blog.

The phase two and three composites are as follows for December. I've used SLP as it replicates the 500 heights well: easy to see why some are looking on with interest if it should follow composite.

 

 

[johnholmes]

 John, you were mentioning the MJO phase in an earlier post - I did some checking last night after reading Mike Ventrice's blog.

The phase two and three composites are as follows for December. I've used SLP as it replicates the 500 heights well: easy to see why some are looking on with interest if it should follow composite.

 

 

 

yep, interesting as you suggest, by 31 December we will all know the answer, but fun trying to decide what may happen for sure.

[nick sussex]

Currently, on the 6-15 day 500mb charts there is little sign of this amplification?

I presume you refer to this Nick

EXTENDED FORECAST DISCUSSIONNWS WEATHER PREDICTION CENTER COLLEGE PARK MD1055 AM EST WED NOV 19 2014VALID 12Z SAT NOV 22 2014 - 12Z WED NOV 26 2014...OVERVIEW...THE LARGE SCALE PATTERN WILL RAPIDLY AMPLIFY DURING THE FIRST HALFOF THE PERIOD TO YIELD A DEEP CNTRL CONUS TROUGH THAT SHOULD DRIFTEWD NEXT MON-WED WHILE A MEAN RIDGE BUILDS TOWARD THE WEST COAST. ASIDE FROM SOME DETAILS THE LATEST MODEL/ENSEMBLE GUIDANCE INTODAY 6 TUE OFFERS REASONABLY GOOD CLUSTERING FOR THE STREAMINTERACTION LEADING TO A DEEP GRTLKS STORM AHEAD OF THE AMPLIFYINGTROUGH AS WELL AS FOR THE UPSTREAM RIDGE.  HOWEVER STARTING AROUNDTUE DIVERGENCE IN SOLNS ARISES DUE TO DIFFS IN FLOW SEPARATIONWITHIN AN ERN PAC TROUGH... ULTIMATELY IMPACTING THE FCST OVER THEWRN HALF OF THE CONUS BY DAY 7 WED.

The anomalous ridging and troughing NOAA talk of is just tha,t anomalous, in terms of long averages for this time in November but not in actual 500mb patterns.

Looking at the 500mb 6-10 and 8-14 I confess to not seeing where the first sentence above comes from. In another  issue those phrases are not there?

I don't think its a long lasting amplification, the initial  re-amplification of the flow is in relation to the deep low crossing the USA between T120 and T168hrs then the flow flattens somewhat.

[johnholmes]

I don't think its a long lasting amplification, the initial  re-amplification of the flow is in relation to the deep low crossing the USA between T120 and T168hrs then the flow flattens somewhat.

 

much as the 500mb charts through days 6-14 have been suggesting for several days in fact.

[swfc]

18z moves pressure slightly higher towards greenland in an islolated kind of lobe???Digging of the jet into the atlantic looks ok so far at 120hrs

[nick sussex]

Maybe the models might just stop all this messing about and just deliver the Scandi high with undercut! please.....

 

I like the earlier trend of the GFS P, the GFS is not up to much, still not convinced the NWP knows what its doing. It will be interesting when we look back at how far west the pattern is pushed because that's been the default signal all Autumn.

Edited November 19, 2014 by nick sussex

[swfc]

Maybe the models might just stop all this messing about and just deliver the Scandi high with undercut! please.....

Think we just missed out again nick!!!!! :sorry:there you go at 264 hrs :rofl:

Edited November 19, 2014 by swfc

[Polar Maritime]

Better Heights over Greenland on tonight's GFSP, The Low much closer to being cut off.

 

[nick sussex]

Think we just missed out again nick!!!!!

Lol ! the GFS finally listened and got there eventually, still don't think much of its earlier trend though, it looks a bit suspicious in how it goes from chump to champ in the lower resolution.

Edited November 19, 2014 by nick sussex

[Ali1977]

And there it is, just as mogreps suggests. Easterly incoming at day 12 and GFS P looking like heading that way too.

GFS doesn't hold on to the high in FI, that means nothing though.

Edited November 19, 2014 by Ali1977

[wolvesfan]

How far out do the MOGREPS ensembles go out to ? Anyone.

http://www.metoffice.gov.uk/research/areas/data-assimilation-and-ensembles/ensemble-forecasting/MOGREPS