Cold hunt - models and chat

[Singularity]

Given those EPS signals BA just reported, a good time to consider GFS’ bias toward overrunning developing blocking to our NE when the Azores High is getting involved. Sometimes that does indeed happen, but as BA rightly pointed out, other times the AH reinforces the Scandinavian one. Results usually pretty dry, mind - at least until the Atlantic tries to find a way back in.

[IDO]

The three main model means at T216 shown as anomalies.

It is apparent that the GEFS suite has greater height anomalies on the three main blocks. It will be interesting to see which way this goes in future runs. Maybe a rogue suite and explains why the GFS op became a massive outlier at the end of the run! 

I suspect the GFS has spotted a pattern change and has overplayed it, all models are notorious at this.

If there are changing variables then expect entropy after the quiet/slack spell, circa D7-D10.

Of course, after that lull, it would be no surprise if the omnipresent Atlantic/Azores High would try to get back in the action, especially with the modelled progress of a PV lobe moving to Pacific>EuroAsia. However, in the current setup, it seems highly unlikely that it will rest as a UK High/Ridge. The next few days should give us a clue going forward as to where that energy goes, the GEFS pretty much cover every base at D16.

A cold 8-10 days ahead with snow opportunities, and then..?

[Mike Poole]

Maybe this should keep us focused as the medium term models continue to churn, ECM T240 zonal winds chart from the Berlin site (yesterday's 12z).  

Downwelling coming to a home near you faster than you think!!

[feb1991blizzard]

3 minutes ago, Mike Poole said:

Maybe this should keep us focused as the medium term models continue to churn, ECM T240 zonal winds chart from the Berlin site (yesterday's 12z).  

Downwelling coming to a home near you faster than you think!!

Followed by a swift return to Westerlies looking at that.

[feb1991blizzard]

9 minutes ago, Singularity said:

Given those EPS signals BA just reported, a good time to consider GFS’ bias toward overrunning developing blocking to our NE when the Azores High is getting involved. Sometimes that does indeed happen, but as BA rightly pointed out, other times the AH reinforces the Scandinavian one. Results usually pretty dry, mind - at least until the Atlantic tries to find a way back in.

Been thinking that recently - That IF February does turn out to be very cold, it could be dry, unless we can get a Scandi block that re-orientates while in situ snapping a chunk of vortex into Russia / Siberia and then timing just right so it heads towards us - unlikely sequence of events that would all need to be timed to perfection.

[Mike Poole]

1 minute ago, feb1991blizzard said:

Followed by a swift return to Westerlies looking at that.

I don't think it works that way.  It's non-linear.  A net easterly flow at our latitude or just above could persist for some time.  Someone correct me if I'm talking out of the proverbial!  Long day 

[MATTWOLVES 3]

Been reading this forum and the two forum for several years now, mainly as a lurker. Some great informative posts from many of you, but also far to much over analysis of every operational run. Something Jon Hammond always says is very risky, not to mention bad for the blood pressure!!! Still learning about the models myself, even though having followed weather for 30 years, and working outdoors for many. So you could say I have an eye for detail and weather patterns. As for the models currently, all over the place, but I stand firm with my belief, and that off the mett office, in that much colder conditions will be prevalent through Feb. Keep up the great posts guys

[feb1991blizzard]

Just now, Mike Poole said:

I don't think it works that way.  It's non-linear.  A net easterly flow at our latitude or just above could persist for some time.  Someone correct me if I'm talking out of the proverbial!  Long day 

Was pseudo in Jest, i honestly cannot call this Mid Feb onwards stuff at the moment - perhaps just edging towards 60/40 against us (proper frigid cold) at the moment.

[kold weather]

Well the ECM ensembles are broadly agreeing with the pattern for Thursday-Friday, but still quite a wide range if pressure ranges. Some still go as deep as 950mbs, although the lower outlier are slowly decreasing. 960mbs seems rougly the placement.

However as I've said before, I think anything below 970mbs is a little unlikely in this set-up, especially if there are competing secondary depressions rotting around, as seems more likely now.

I have to say there really is a lot of very subtle variations that make a big difference to the actual weather. For example a few runs have a weak secondary depression that works along the channel and effectively dumps 3-5 inches in the far south. Whilst that's an unlikely set-up, it shows how complex this set-up. This probably won't be settled until the day I suspect due to the little features I've talked aboutl

[Kirkcaldy Weather]

ensembles GEM 12z

   

     

ensembles FNMOC/NOGAPS 12z

     

Looks like it could be all eyes toward scandi after this weeks possible fun and games.

[Mike Poole]

4 minutes ago, Mattwolves said:

Been reading this forum and the two forum for several years now, mainly as a lurker. Some great informative posts from many of you, but also far to much over analysis of every operational run. Something Jon Hammond always says is very risky, not to mention bad for the blood pressure!!! Still learning about the models myself, even though having followed weather for 30 years, and working outdoors for many. So you could say I have an eye for detail and weather patterns. As for the models currently, all over the place, but I stand firm with my belief, and that off the mett office, in that much colder conditions will be prevalent through Feb. Keep up the great posts guys

Hi @Mattwolves welcome to the mad house! And in the most frenetic period of the year, winter yes, but with the added bonus of wintry weather possible next week and for the rest of February.  You join us at interesting times for sure!  Welcome!

[alexisj9]

2 hours ago, Mark wheeler said:

Yummy  

Go Go super ecm 

If only the draw wasn't from a relatively warm Italy. We still have cold, so hopefully will be alright.

[kold weather]

18z ICON rolling, won't take long tonight to get to the points of real interest. Wonder what direction ICON will go this time, its been really inconsistent with how it evolves both lows the last 3-4 suites.

[MATTWOLVES 3]

1 minute ago, kold weather said:

18z ICON rolling, won't take long tonight to get to the points of real interest. Wonder what direction ICON will go this time, its been really inconsistent with how it evolves both lows the last 3-4 suites.

 

[CSC]

ICON model may have been inaccurate in recent times but it has been the one to sniff trends on some occasions. Lets hope it increases the snow event for the UK!

Important and nervous times ahead..

[nick sussex]

I wish this Channel Low would make up its mind .

The envelope of solutions are ridiculous given the timeframes . I think a big issue is how much it deepens .

The UKMO drops it to 980 and this  helps to keep it on  a more northerly track .

 

[Mike Poole]

5 minutes ago, Mattwolves said:

Cheers Mike, appreciate it. One thing I've had on my mind recently....... I've noticed many posts reffering to BBC forecasts as very often being out of date, (ie) an evening forecast going on morning data, now as I'm sure most of you knowledgeable folk will no, the presenters are actually met office trained and not meteo group trained. So I often wonder if some of the more experienced forecasters are actually agreeing with the data they have in front of them!!! At times it's like they issue a forecast, yet they are skeptical in what they are saying! Just a thought, not sure how many of you would agree. Sorry for going a little out of topic mods, just something that's been on my mind since the BBC changed Provider

Yes I would certainly agree with that personally, but probably best discussed in the general media thread, rather than the model thread.  BBC now have access to only a bit more model output than we do here!  The main advantage ECM ensembles, but they don't help on the timescales they are forecasting for!  

[Ben Sainsbury]

By T33 on the ICON 18z there are already hints of the low being a tad further northwards as a result of it being a little deeper too!

[bluearmy]

7 minutes ago, Mattwolves said:

Cheers Mike, appreciate it. One thing I've had on my mind recently....... I've noticed many posts reffering to BBC forecasts as very often being out of date, (ie) an evening forecast going on morning data, now as I'm sure most of you knowledgeable folk will no, the presenters are actually met office trained and not meteo group trained. So I often wonder if some of the more experienced forecasters are actually agreeing with the data they have in front of them!!! At times it's like they issue a forecast, yet they are skeptical in what they are saying! Just a thought, not sure how many of you would agree. Sorry for going a little out of topic mods, just something that's been on my mind since the BBC changed Provider

given that the extended eps are complete about 8-15pm, i’m not sure there is time for a proper assessment to be made of the 12z runs and for them to be included in a 9 or 10pm forecast.  I used to feel that the met office backed bbc 10pm output reflected the evening ec output if it was different but since meteogroup took over, I’m not sure that’s the case. it could simply be that the economics of meteogroups set up doesn’t allow for it. 

[shaky]

Icon low is deeper at 33 hours

[MATTWOLVES 3]

3 minutes ago, kold weather said:

18z ICON rolling, won't take long tonight to get to the points of real interest. Wonder what direction ICON will go this time, its been really inconsistent with how it evolves both lows the last 3-4 suites.

I admire your optimism kold, what surprises me is how so many on here await the 18z run!!! As regards to data it as alongside the 6z less information inputted then say, the 0z and 12z, no wonder the americans take more note of the ecm!! 

[MattStoke]

7 minutes ago, kold weather said:

18z ICON rolling, won't take long tonight to get to the points of real interest. Wonder what direction ICON will go this time, its been really inconsistent with how it evolves both lows the last 3-4 suites.

Slightly further north, so far.

[I remember Atlantic 252]

4 minutes ago, nick sussex said:

I wish this Channel Low would make up its mind .

The envelope of solutions are ridiculous given the timeframes . I think a big issue is how much it deepens .

The UKMO drops it to 980 and this  helps to keep it on  a more northerly track .

 

think its rain anyway, you are definitely south of the low

[MATTWOLVES 3]

2 minutes ago, bluearmy said:

given that the extended eps are complete about 8-15pm, i’m not sure there is time for a proper assessment to be made of the 12z runs and for them to be included in a 9 or 10pm forecast.  I used to feel that the met office backed bbc 10pm output reflected the evening ec output if it was different but since meteogroup took over, I’m not sure that’s the case. it could simply be that the economics of meteogroups set up doesn’t allow for it. 

Good point blue, cheers for clarifying that

[phil nw.]

Let's keep the chat around the weather charts please all.The team have again being hiding off topic stuff all day which would otherwise trash the thread and take things way off topic.

Please use the relevant threads for other chat.Football talk in the sports zone,BBC forecasts in the media thread and the Met office outlooks in their thread  etc.etc You should all know the drill by now.

Ta very muchly.