Model output discussion - 7th January onwards

[Penicuikblizzard]

1 hour ago, Steve Murr said:

Morning 

ICON is the same as the 12z ECM yesterday ( just a shade colder)- which is great 

UKMO is ok - colder than yesterday - it has the same trough as ICON at 144 over Iceland, just a bit further NE-

Aperge very good @96 as well-

GFS - not even viewed now.

 

 

Why not view GFS?

[Banbury]

Just gone through the final stages of FI in the GEFS , there are some very good one's its just the 850's that are a let down

[Banbury]

15 minutes ago, Spah1 said:

 Another day/2 days later the uppers would be very cold. 

As explained a million times they don’t need to be -10 in a flow from the East. 

I think the comment was on the 216 and 240 , not what's to follow 

Edited January 15, 2019 by Polar Maritime
To move discussion on.

[ItNeverSnowsInWindsor]

We need to see the UKMO on board this evening as it looks to put too much energy SE of Greenland and powering up the northern arm of the jet subsequently.

[SMU]

6 minutes ago, Penicuikblizzard said:

Why not view GFS?

Why have stewing steak if fillet & ribeye are the same price....

[winterof79]

13 hours ago, ghoneym said:

Regarding GFS output, I would have a read of this. Its still relevant. The government shutdown is affecting it, no doubt in that. https://www.washingtonpost.com/weather/2019/01/07/national-weather-service-is-open-your-forecast-is-worse-because-shutdown/?noredirect=on&utm_term=.c917a9b7b0ee

I would take the GFS and the FV3 with a very large rich of salt and on to compare long term trends, and even at that I would say don't trust it.

#penicuikblizzard

Do please read this before taking ANY GFS output seriously at present.

Edited January 15, 2019 by winterof79

[bluearmy]

Ecm progressive but fits in with its general ens guidance ..... that Iceland upper ridge is way too strong days 9/10 but the op tends to overdo what will be close to what becomes the new theme  ....

however, ncep is FLAT......and gem trends that way later on (against its ens guidance I might add) 

the mist should be clearing .......but it’s getting a bit foggy ......the loss of support from the para is annoying ..... will give it another couple runs before being overly concerned .....

clearly the strat/trop interaction is causing issues with continuity ........ not sure I trust the MJO analogues much .... they didn’t reflect well last cycle later on (although the speed of the thing later on probably meant that was going to be tough!). And as we head towards the back end of the month, would they be jan or feb analogues ..... or a blend ............

[That ECM]

Yesterday’s fax and today’s gfs. Roughly for the same t plus look to our north. Fax 1020 wedge. Gfs 985 low. Not much support there for the gfs is there?

Edited January 15, 2019 by That ECM

[winterof79]

10 minutes ago, prolongedSnowLover said:

We need to see the UKMO on board this evening as it looks to put too much energy SE of Greenland and powering up the northern arm of the jet subsequently.

I don't get where your coming from as ECM has more energy at 120z than UKMO

[Penicuikblizzard]

6 minutes ago, winterof79 said:

#penicuikblizzard

Do please read this before taking ANY GFS output seriously at present.

Ah right I didn’t realise there was a lack of data going into the model just now

[BLAST FROM THE PAST]

8 hours ago, kold weather said:

THe big difference between the 18z GFS op and the other 12z suite including the UKMO is how it handles the Arctic High. In all other models it keeps the Arctic high intact.

The 18z GFS cleves it and forms a new proto PV exactly where the ECM has the arctic high by 168hrs.  if you watch that lobe it eventually forms the PV lobe over NE Canada and hence why the patterns starts to flatten out by 216hrs again.

That's why the 18z is garbage compared to the other runs.

In general not a specific run, I wasn’t referring to 18z.

lets hope the 00z is million miles wrong though.

BFTP

[winterof79]

3 minutes ago, Penicuikblizzard said:

Ah right I didn’t realise there was a lack of data going into the model just now

Seriously hope this is legit

[IDO]

ECM keen on disruption of the systems as early as D6 enabled it by some nicely placed wedges to direct the flow SE. Not saying that this is not possible, but only one of the GEFS is close (not really) to that scenario. The GEFS don't start to disrupt the pattern till closer to D10.

 Wedge perfectly placed close to NE Iceland to deflect lower heights SE!

The ECM is just another possible route but I still believe entropy rules, although we can hope that ECM is right, but its bias towards overdoing pattern changes when it spots one would be a concern.

As for the GFS, rather uninspiring in the medium term, flatter and taking several efforts to clear some lower heights from the NW before it is willing to drop into the Euro trough large scale. FI remains positive and it appears the GEFS want to bring HLB'ing for late Jan.

Conclusions will have to wait for a few more runs IMO.

[nick sussex]

Good grief what’s going on!

The GFS and ECM inhabit different planets . The UKMO not as good as the ECM but not a disaster by any means .

This is now where handling of the big USA storm is important at day 6 and 7. The ECM has the more amplified storm which runs ne and attaches to the PV lobe over ne Canada , if you follow day 6 and then 7 on the NH chart you can clearly see how it helps to pull the PV lobe further nw allowing the slider low to separate from that lobe .

The GFS is flatter and you can see the results downstream .

Will be interesting to see what NCEP make of this.

 

[Johnp]

3 minutes ago, bluearmy said:

Ecm progressive but fits in with its general ens guidance ..... that Iceland upper ridge is way too strong days 9/10 but the op tends to overdo what will be close to what becomes the new theme  ....

however, ncep is FLAT......and gem trends that way later on (against its ens guidance I might add) 

the mist should be clearing .......but it’s getting a bit foggy ......the loss of support from the para is annoying ..... will give it another couple runs before being overly concerned .....

clearly the strat/trop interaction is causing issues with continuity ........ not sure I trust the MJO analogues much .... they didn’t reflect well last cycle later on (although the speed of the thing later on probably meant that was going to be tough!). And as we head towards the back end of the month, would they be jan or feb analogues ..... or a blend ............

Have you read the Washington post article? We shouldn't be worrying too much about what any GFS run is showing at the moment.

[Leo97t]

Omg that is one of the largest differences between 240hr runs I've ever seen. Suspect ecm is gonna have egg on the face. When there is cross-section model disagreement. Always pick the less favourable solution - it's almost always right

[nick sussex]

Could someone kindly summarize what the WP says about the shutdown . Not been able to read the article as it’s behind a paywall .

Edited January 15, 2019 by nick sussex

[snowking]

14 hours ago, ghoneym said:

Regarding GFS output, I would have a read of this. Its still relevant. The government shutdown is affecting it, no doubt in that. https://www.washingtonpost.com/weather/2019/01/07/national-weather-service-is-open-your-forecast-is-worse-because-shutdown/?noredirect=on&utm_term=.c917a9b7b0ee

I would take the GFS and the FV3 with a very large rich of salt and on to compare long term trends, and even at that I would say don't trust it.

There was some discussion about this on Twitter when this article was published - essentially, NWS forecasters themselves came forward and said there was no truth to this as far as they knew

https://twitter.com/everythingwx/status/1083039436257017857?s=21

And then came this from the deputy administrator of NOAA

https://www.postandcourier.com/opinion/commentary/weather-prediction-still-accurate-even-during-shutdown/article_6944faba-15d3-11e9-96ea-b79ddbf38e0b.html

So I think any thoughts that the government shutdown has affected GFS performance are as unfounded as the whole ‘lack of data’ fallacy we get over Christmas every year

[Weather Boy]

2 minutes ago, Leo97t said:

Omg that is one of the largest differences between 240hr runs I've ever seen. Suspect ecm is gonna have egg on the face. When there is cross-section model disagreement. Always pick the less favourable solution - it's almost always right

Hopefully a tongue in cheek comment?

If not, very unscientific as it literally means that you are allowing your emotions to determine which model output is likely to be correct!

[feb1991blizzard]

2 minutes ago, Leo97t said:

Omg that is one of the largest differences between 240hr runs I've ever seen. Suspect ecm is gonna have egg on the face. When there is cross-section model disagreement. Always pick the less favourable solution - it's almost always right

Seen it many times before.

[karlos1983]

36 minutes ago, Banbury said:

Before anyone gets the Champs out  see where it sits - ECM is a cracking run 

It will be a warm outlier in terms of 850’s I’d say. Synoptically probably a bit eager as well. Just my opinion But what a run it was! 

Staggered the gfs is still not budging! Look forward to hearing ncep thoughts when Nick reports back.

[winterof79]

GFS loses its way by day 5 and thereafter is all over the shop and the GEFS can't be any better 

Here it is compared to ECM at that period.

 

[daz_4]

2 minutes ago, nick sussex said:

Could someone kindly summarize what the WP says about the shutdown . Not been able to read the article as it’s behind a paywall .

You can click on the free option and it will let you read it 

Edited January 15, 2019 by daz_4

[Chris.R]

19 minutes ago, winterof79 said:

#penicuikblizzard

Do please read this before taking ANY GFS output seriously at present.

 I brought this up yesterday. There’s definitely  something not right with the GFS. With all the chaos going on with the shutdown there’s bound to be a significant effect. 

[bluearmy]

The gfs stuff is nonsense - noaa cpc are still using it in their blended output .... there is nothing more to add on this whilst that continues to be the case