Model Output Discussions 12z 01/09/2016

[Summer Sun]

Once the northeasterly is out the way the ECM ens introduces a northwesterly for the remainder of the run

 

 

Edited October 31, 2016 by Summer Sun

[BurwellWeatherWatch]

1 hour ago, knocker said:

Interesting ecm run this evening. The divergence from the 00z and the start of some high jinks starts at T144, Here the mid Atlantic ridge extends further north and blocks the Canadian vortex eastward energy transfer. Not to be out done it redirects it SE and combines with the energy that has been tracking along the eastern seaboard to form a new trough in the western Atlantic. Thus we have this analysis with the combination of the ridge and European trough producing cold northerlies over the UK

From here until T216 the mid Atlantic HP is shunted NE into Scandinavia introducing some warm air into that area whilst the trough in the west reestablishes the strong link to the Canadian vortex and tracks east  Thus a strong upper trough is established in mid Atlantic, slight ridging over the UK with a cold pool central Europe.

In short we are looking at an unsettled, wet at times, cool bordering on cold weekend and the beginning of the next week before a brief quieter period as the HP pops in before the Atlantic says hello with a vengeance with the arrival of fronts from the west and strong winds.

Would you be able to explain where the Atlantic charges back in because I can't see that in the charts....

[Frosty.]

I can't see anything mild on tonight's Ecm 12z ens mean I'm delighted to say!

[Day 10]

Lets hope the models are just practicing with variations of blocking

Before finally nailing a doozy in Jan!!!

[knocker]

58 minutes ago, BurwellWeatherWatch said:

Would you be able to explain where the Atlantic charges back in because I can't see that in the charts....

Well I can't post the 6 hourly charts but in the chart I have already posted at T216 the Atlantic trough is already making inroads on th ridge, This continues and you have this somewhat complex analysis at the end of the run. Frankly I thought it clear enough on my earlier post

But I wouldn't worry too much about it as the EPS ens has the det as an outlier. It was completely dependent on the mid Atlantic HP surging into Scandinavia thus allowing the trough eastward progress. This doesn't happen with the ens and so the energy transfer will still remain to the north of the ridge and SE into Britain

Edited October 31, 2016 by knocker

[Man With Beard]

24 minutes ago, Summer Sun said:

Once the northeasterly is out the way the ECM ens introduces a northwesterly for the remainder of the run

 

 

This is the point for me. Whether we get a "cobra" run or not, high pressure remains out in the Atlantic and Europe tends to attract lower pressure. That means the mildest air will tend to stay away from the UK, only affecting us for a day or two at a time. And it also means that heights are well positioned to dart north again behind any passing troughs in the Atlantic. I would not rule out Steve Murr's second trigger low yet after the one coming up for this weekend. 

In short, the pattern remains primed to keep the UK in receipt of northerly tendencies rather than southerly ones, probably for the next 14 days.

[Frosty.]

2 minutes ago, Man With Beard said:

This is the point for me. Whether we get a "cobra" run or not, high pressure remains out in the Atlantic and Europe tends to attract lower pressure. That means the mildest air will tend to stay away from the UK, only affecting us for a day or two at a time. And it also means that heights are well positioned to dart north again behind any passing troughs in the Atlantic. I would not rule out Steve Murr's second trigger low yet after the one coming up for this weekend. 

In short, the pattern remains primed to keep the UK in receipt of northerly tendencies rather than southerly ones, probably for the next 14 days.

It's a win win for coldies, either we get atlantic lows sliding SE under the block as per the Ecm 12z operational or we have a nw / se jet axis with predominantly polar maritime occasionally veering towards the arctic as the gefs / ecm ens mean show.

[karlos1983]

That's a not to snappy ensemble mean right there folks, just look at that up north. Nice!

[knocker]

Marked lack of cold air around in eastern Europe. The EPS is similar. Still WAA continuing in North. N.America

 

[Man With Beard]

1 minute ago, knocker said:

Marked lack of cold air around in eastern Europe. 

 

...because it's over here instead

[feb1991blizzard]

1 minute ago, knocker said:

Marked lack of cold air around in eastern Europe. The EPS is similar. Still WAA continuing in North. N.America

 

slight +ve 850mb anomalies over Greenland as well./

[knocker]

3 minutes ago, feb1991blizzard said:

slight +ve 850mb anomalies over Greenland as well./

Well you could say in the western Atlantic and slight -ve in the Scandinavian trough.

Edited October 31, 2016 by knocker

[feb1991blizzard]

Just now, knocker said:

Well you could say in the western Atlantic and slight -ve in the weak Scandinavian trough.

You could indeed sir, and you could say theres a marked lack of +ve temp anomalies over the UK which had been prevalent in a lot of Novembers in the last 10 years with the notable exception of Late Nov 2010 of course.

[knocker]

5 minutes ago, feb1991blizzard said:

You could indeed sir, and you could say theres a marked lack of +ve temp anomalies over the UK which had been prevalent in a lot of Novembers in the last 10 years with the notable exception of Late Nov 2010 of course.

Indeed you could sir but the trend is perhaps cause for concern

 

Edited October 31, 2016 by knocker

[Ice Day]

The pub run is showing the 0 degree 850's clearing the south coast on Saturday evening with -4's across Scotland/North England.  A cold Guy Fawkes night on the cards.

 

[Man With Beard]

1 minute ago, knocker said:

Indeed you could sir but the trend is perhaps cause for concern

That's a really fascinating chart you put up there. On the one hand, you could say the cold anomaly is weakening, and perhaps the Atlantic is revving up for the 2nd half of November. But Europe is still cold and Scandinavia extremely cold. And look at all that warmer than average air up in northern latitudes - the tip of Greenland is almost off the scale! How on earth is it staying so warm up there? And surely warm there means colder somewhere else...

[feb1991blizzard]

Just now, knocker said:

Indeed you could sir but the trend is perhaps cause for concern

Slight concern at the moment wrt the Atlantic, I will let you know though when my concernometer is middling (in your words) or severe!!

[Ravelin]

Well the GFS 18z is well on it's way out and there wasn't much difference up to t120, after that there's more of a NE direction to the winds and maybe better heights up towards Greenland compared to the 12Z.

12z     18z

[weirpig]

Differences again at 144 on the 18z different shape ridging into Greenland and more of a northerly effecting the uk  doh beaten to it 

Edited October 31, 2016 by weirpig

[Barry12]

Much better, 18z on the left...

 

Edited October 31, 2016 by Barry95

[Ice Day]

On the face of it the charts 120 through 150 look very nice, but in reality the coldest air never really makes it across the north sea.  However, it will no doubt still feel more than nippy in any breeze. Good charts to see though so early in the season:

 

[knocker]

9 minutes ago, Man With Beard said:

That's a really fascinating chart you put up there. On the one hand, you could say the cold anomaly is weakening, and perhaps the Atlantic is revving up for the 2nd half of November. But Europe is still cold and Scandinavia extremely cold. And look at all that warmer than average air up in northern latitudes - the tip of Greenland is almost off the scale! How on earth is it staying so warm up there? And surely warm there means colder somewhere else...

Well in my book only a fantasist would say that and as far as I'm aware they are all gathered on the  other side of the spectrum. So to speak.

Edited October 31, 2016 by knocker

[Barry12]

4 minutes ago, Ice Day said:

On the face of it the charts 120 through 150 look very nice, but in reality the coldest air never really makes it across the north sea.  However, it will no doubt still feel more than nippy in any breeze. Good charts to see though so early in the season:

 

 

The cold is more prolonged though

 

Edited October 31, 2016 by Barry95

[legritter]

2 hours ago, virtualsphere said:

http://fim.noaa.gov/

Not sure how reliable it is, I haven't heard much about it so it would be interesting to get some views from the experts.

This fim model I looked up today ,looks interesting ,I put in fim on Google . Made interesting read .cheers .you need to type in Fim weather model .

Edited October 31, 2016 by legritter

[Frosty.]

Charts like these are just delightful from the Gfs 18z, especially knowing the timeframe involved is still 3 weeks away from the start of the new meteorological winter! I have a feeling coldies cups will runneth over during the next 5 months!

Edited October 31, 2016 by Frosty.