Jump to content

Model Output Discussion; into 2015


Recommended Posts

Mild sector looks very transient on friday before much cooler air on Saturday on GFS 12Z OP, don't overexaggerate the coming weeks mildness, you also forgot to mention the warm sector bringing a spell of heavy rain friday.

Same old story though isn't it, these cooler spells bring temperatures of 4-6C which in the scheme of things is only around 2 or 3 degrees below normal, meanwhile those milder spells (however transient) can deliver daily CET of 10C+. Again like last month despite a lot of claims about the lack of milder weather, we will likely be sitting at a above to well above average figure in respect to the monthly average.

Temperatures at midday from the parallel

Tomorrow

ukmaxtemp.png

4 or 5C, strangely not as cold as the models were saying a day or so ago. Some areas of course colder where fog is likely to linger.

 

Monday

ukmaxtemp.png

Generally 7-9C though some areas do reach double figures.

 

Tuesday

ukmaxtemp.png

Mild in the east (9-11C), cooler conditions spreading east during the day with an associated cold front.

 

Wednesday

ukmaxtemp.png

Reverse scenario with a warmth front pushing eastwards, the east is near or slightly below normal (5-7), whilst double figures are achieved over Ireland with these spreading east overnight.

 

Thursday

ukmaxtemp.png

Temperature near or a little above normal in the south, cooler than average in the north.

 

Friday

ukmaxtemp.png

The day of the potential windstorm over Scotland - double figures across the board. Overnight is very mild.

 

Saturday - a week away.

ukmaxtemp.png

The very mild weather is gradually displaced south eastwards. But the south gets another mild day.

 

Overall it's a typical story of a mix of tropical maritime and polar maritime incursions. Neither taking total control. I don't understand your complaint as my post was making the point where there is the greatest movement away from average (in terms of temperature). Ultimately the week ahead shows temperatures a little above normal (a +1C anomaly looks likely). This is also backed up by other models and professional forecasts. The second half of the month looks to be cooler but at the present time I see not much more than a repeat of December where we may see a spell of 3-5 days of colder and drier weather which will bring temperatures over the month to near normal levels.

 

Up to day 10, no sign of a relenting jetstream on the GFS/Parallel or GEM, the most interesting is some very low heights developing over the UK into the start of low-res potentially bringing widespread heavy rain and strong winds. GEM/Parallel keep a similar theme to day 10 before again both the GFS/Parallel show a change to colder and drier conditions at the end of week 2/start of week 3. I must say that the parallel does mange to achieve the same result as the previous couple of runs with a north/north easterly establishing which is nice to see (consistency but is it reliable?)

Edited by Captain shortwave
  • Like 2
Link to post
Share on other sites
  • Replies 1.8k
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Popular Posts

12z clusters are offering glimpses of a different story after mid-month with markedly more meridional pattern(s), but of course it's just not worth detailing all that stuff showing out post-15 Jan unt

Some very poor quality posts have been creeping into the discussion which really don't add anything to the thread apart from raising the ire of many who view this thread....Even a simpleton (in meteor

Nice tease from the ECM, no surprise looking at the strat charts, shame it can't happen though because apparently cold is not possible before Mid Jan!?!   Rule nothing out folks, as I posted yeste

Posted Images

Thank you for the reply. If the cold air comes far enough South in the USA will it have the same effect on the jetstream as the displaced vortex did last year? Therefore giving us some possibly some gales?

Funnily enough, the the cold air coming south again later in that gfsp run actually helps to amplify the pattern to the degree that it blows up the greeny ridge. So a cold blast in the east states could actually work in our favour this year. don't assume cold conditions there will result in the same thing for us as last year.

  • Like 6
Link to post
Share on other sites

GFSP in FI Greenland heights shock!!! :shok:

 

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=384&mode=0&runpara=1

 

Of course at that range, not worth reading too much into. I suspect come the day a more traditional mid Atlantic ridge will be the outcome, but its still nice see some decent eye candy.

 

If we start to see lots of these though on GFS I'm personally going to be very wary indeed of buying into it as I think GFS (and its ensembles) have a lot of previous around Greenland height rises (and I don't just mean from the pre Christmas fun and games). 

 

All of that said, developments today can only be seen as positive.

  • Like 3
Link to post
Share on other sites

This has been the phantom winter thus far be it Strat warming and northern blocking.  Although nice to see it is very deep FI and just something to be kept an eye on.  It could be that it is picking up early on something serious [as 2010 showed] and with all the early positives its not beyond realms of reason but having said that look at where we currently are and lets tread cautiously with feet on the ground.  But if I must

 

gfs-0-372.png?12

 

:smiliz19:

 

BFTP

  • Like 4
Link to post
Share on other sites

As a basic trend I will be monitoring the trend for high pressures being centred over the pole enforcing the cold pool to our NE IF it enters a reasonable time frame.That didn't last long i already have.

  • Like 1
Link to post
Share on other sites

It may be wise for now to remain a little cautious about FI GFS (and indeed GEFS) output. Why? Well the GEFS is fairly solidly behind a progression towards MJO phase 7 (unfortunately there are issues with the MJO images today), however it is rather isolated in this assertion, with just some limited support on offer from the BOM:

 

BOMM_phase_33m_small.gif

 

Otherwise we see the other major suites repressing the signal in to Phase 6:

 

JMAN_phase_51m_small.gifECMF_phase_MANOM_51m_small.gifUKME_phase_23m_small.gif

 

(Should be noted the last one there from MOGREPS-G may be a little more difficult to call)

 

We can see where the FI GFS suggestions are coming from if we take a look at the Phase 7 composite:

 

JanENMJOphase7all500mb.gif

 

However during the previous MJO wave the GEFS was pretty poor. That is not to say that will be the case this time around, but right now it looks very much like GFS v the rest.

 

Until we see a more coherent signal, caution is advised

 

SK

 

 

You say it's GFS v the rest but the period of interest/possible change doesn't happen until around 276H

 

GFS

Rtavn2761.gif

 

GFS parallel

 

Rpgfs2761.gif.

 

That is out of the range of ECM/UKMO/JMA/GEM amongst others. Also I'm not too sure on the accuracy of MJO induced forecasts but I can't see it being the be all and end allof what will happen.

 

Hopefully though the ECM 12z may just be getting into the range were we can see if it agrees with the GFS so could be quite interesting the last couple of frames. Yes FI but we have to start somewhere after such a dire few days of output. : )

Edited by Harsh Climate
  • Like 8
Link to post
Share on other sites

Didn't we see a Greenland high trying not so long ago ?

If I remember rightly the pv was not at strength like it is now!.

If it continues for the next five days with other models suggesting the same then the guard is dropped.

But that's not to say a 1070mb Greenland height is not eye candy!.

But in honesty very unrealistic considering in 09/10 Greenland heights reached 1050mb maybe 1060mb but that was the most exciting block I seen for some years.

So although beautiful to see very unlikely also the nao and AO were pretty amazing to not likely to see that this winter.

  • Like 1
Link to post
Share on other sites

There was a synergy between the 00z gefs and 00z ECM extended.

There are enough varying options on the gefs to make any assumptions a little premature but the fact that the anomolys are showing high to the west and low to the east is promising at this stage. The next few days will reveal if a) the signal begins to firm up and b) does it look to become mobile again thereafter?

  • Like 1
Link to post
Share on other sites

Anomalies

 

gensnh-21-5-324.png

 

gensnh-21-5-348.png

 

Very strong signal for Height rises in the mid Atlantic which has been showing in the GEFS for a while now.

 

Didn't we see a Greenland high trying not so long ago ?
If I remember rightly the pv was not at strength like it is now!.

If it continues for the next five days with other models suggesting the same then the guard is dropped.

But that's not to say a 1070mb Greenland height is not eye candy!.

But in honesty very unrealistic considering in 09/10 Greenland heights reached 1050mb maybe 1060mb but that was the most exciting block I seen for some years.

So although beautiful to see very unlikely also the nao and AO were pretty amazing to not likely to see that this winter.

 

True. Very true indeed so caution is obviously advised. But the trend is there and it only gains stronger so it can't be ignored especially when both GFS runs arrive to similar synoptics just the potency is the change.

 

 

And to give back life to the coldies there's always light at the end of the tunnel.

 

cfs-0-576.png?12

Edited by SN0WM4N
  • Like 4
Link to post
Share on other sites

Well looking a bit closer in FI land this little feature is something that we need to keep an eye on.  Otherwise bar Sunday and Wednesday generally on the mild side and on some days it looks more like early march than early Jan.

 

post-2404-0-45382100-1420308738_thumb.pn

  • Like 2
Link to post
Share on other sites

12z GEFS for East Iceland are interesting;

post-12721-0-07878600-1420308827_thumb.j

Pretty clear signal for a pressure rise in that area in 7+ days time. What sort of pressure rise and how this will affect the North Atlantic weather pattern is much less clearer at this stage.

Op, Paralell and Control pretty much the 3 most bullish runs in this respect.

Edited by AWD
  • Like 5
Link to post
Share on other sites

I'm guessing around the 18th dec 2014. don't have the time to check if out but anyone with 5 mins can check the archive gfs/p fi's on meteociel. Maybe not in the same detail but there were some very wintry runs around that timescale.

 

I'd be delighted to look for you if you point me to the link. But I would have looked at the outputs on GFS, PFSP and ECMW plus more every day myself but never saw this set up, most of those were northerly set ups, polar express solutions.

Link to post
Share on other sites

12z GEFS for East Iceland are interesting;

attachicon.gifimage.jpg

Pretty clear signal for a pressure rise in that area in 7+ days time. What sort of pressure rise and how this will affect the North Atlantic weather pattern is much less clearer at this stage.

Op, Paralell and Control pretty much the 3 most bullish runs in this respect.

 

I think these baby steps to something more fruitful have certainly gained pace over the last day or so.

 

A huge IF but if the gfs does prove to be close to the mark in what it's showing in two weeks time, It would be an almighty personal victory for the GFS  :w00t:

  • Like 2
Link to post
Share on other sites

You say it's GFS v the rest but the period of interest/possible change doesn't happen until around 276H

 

GFS

Rtavn2761.gif

 

GFS parallel

 

Rpgfs2761.gif.

 

That is out of the range of ECM/UKMO/JMA/GEM amongst others. Also I'm not too sure on the accuracy of MJO induced forecasts but I can't see it being the be all and end allof what will happen.

 

Hopefully though the ECM 12z may just be getting into the range were we can see if it agrees with the GFS so could be quite interesting the last couple of frames. Yes FI but we have to start somewhere after such a dire few days of output. : )

 

Hi HC,

 

Both the ECMWF and JMA MJO forecasts go out beyond day 10 (out to day 15 I believe) - the MOGREPS forecast displayed there only goes to 10 days, hence the attached note.

 

It is in that crucial Day 10-15 period that the disagreement takes place in terms of the MJO phasing. As stated, just because the GEFS was poor on predicting it last time does not mean that will necessarily be the case this time, but it would be wise to remain cautious until we see a more unanimous agreement between suites on this signal. Still some question marks as to whether this is MJO induced, but given the close resemblance to MJO phase 7 composites that would be an acceptable assumption for now.

 

SK

Edited by snowking
  • Like 3
Link to post
Share on other sites

I'm guessing around the 18th dec 2014. don't have the time to check if out but anyone with 5 mins can check the archive gfs/p fi's on meteociel. Maybe not in the same detail but there were some very wintry runs around that timescale.

 

Hi Bluearmy; I was looking back at previous posts and this chart was posted on the 21st dec for the 28th dec, its a cold set up, but low is to the north east and its polar flow. http://www.meteociel.fr/modeles/jma/runs/2014122112/JN168-21.GIF?21-12

Edited by David Morse
Link to post
Share on other sites

Hi HC,

 

Both the ECMWF and JMA MJO forecasts go out beyond day 10 (out to day 15 I believe) - the MOGREPS forecast displayed there only goes to 10 days, hence the attached note.

 

It is in that crucial Day 10-15 period that the disagreement takes place in terms of the MJO phasing. As stated, just because the GEFS was poor on predicting it last time does not mean that will necessarily be the case this time, but it would be wise to remain cautious until we see a more unanimous agreement between suites on this signal. Still some question marks as to whether this is MJO induced, but given the close resemblance to MJO phase 7 composites that would be an acceptable assumption for now.

 

SK

The GFS is known to have a bias towards continuing any tropical convection into phases 7/8. I can't sem to get the link to work currently but the bias corrected NCPB ensembles normally autocorrect the NCPE. If someone can put these up I'd be grateful.

Link to post
Share on other sites

Hi HC,

 

Both the ECMWF and JMA MJO forecasts go out beyond day 10 (out to day 15 I believe) - the MOGREPS forecast displayed there only goes to 10 days, hence the attached note.

 

Not sure about the website you cite, but native EC version goes to day 20; MOGREPS to 15.

  • Like 2
Link to post
Share on other sites
Guest
This topic is now closed to further replies.
×
×
  • Create New...