Jump to content

Model output discussion - proper cold spell inbound?


Recommended Posts

  • Replies 3.7k
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Popular Posts

Evening All  Ice Cold hope your still with us .... So the much touted SSW is coming into view & here’s my thoughts + timelines of when / where to expect it... We have seen lots of p

Well it's probably fair to say that I've been rather quiet on these forums for the last few years really, especially since 2013. After 15 years of internet weather watching, and more importantly,

Well - ho hum - let's have a sit rep. My eyes are hanging out on stalks.  The pacific first - engine of the climate system. How is our AAM looking in the face of the current high amplitude MJO?

Posted Images

2 minutes ago, karlos1983 said:

I’m not worried, I was just a bit taken back. It’s made more difficult by not seeing individual runs like we get to see in graph format for the GEFS. So I am at risk of contradicting what I said earlier about the mean if the graph has the same look about it as the GEFS did. I.e. couple of very warm runs skewed the mean. :)

An output is an output. For all the great charts, when you drop in a mean chart, you can`t dismiss it just because it isn`t what you hoped for. Going to be nervy viewing.

  • Like 1
Link to post
Share on other sites
7 minutes ago, Stuie W said:

An output is an output. For all the great charts, when you drop in a mean chart, you can`t dismiss it just because it isn`t what you hoped for. Going to be nervy viewing.

Well, a mean chart is just a blend of the model suites members though, not an individual run (to my understanding) So if you’ve got 8 really cold members and 8 reging westerly members there’s probably not going to be a middle ground! One will be wrong and therefore so will the mean! 

My point about the ECM is we don’t get to see without ploughing through that weather.us site viewing each member in isolation what the individual runs are doing. Like that GEFS graph, clearly 2 runs very warm compared to the rest, which will automatically rise the average/mean temperature. Anyway we may derail. 

Edited by karlos1983
  • Like 3
Link to post
Share on other sites
10 minutes ago, mulzy said:

Extended eps stays on track; higher than normal heights to the north, lower than normal heights to the south.  Slight change of emphasis in that towards the later end (days 14-15), the focus of the higher heights is moving west towards eastern Greenland.

Great news :) I expect a colder set on the debilt ext ens after hearing this. 

  • Like 1
Link to post
Share on other sites

Whenever I've seen a mean 1030mb high in a place where it doesn't usually happen, 9/10 it verifies in that place. However, considering the scatter in the diagram for North Sweeden, I won't call it for a few runs yet.

gens-21-1-360.png   graphe4_1000___16.1320754717_65.30364372

NOAA 8-14 starting to see Scandi heights too but still a "work in progress"

814day.03.gif

  • Like 3
Link to post
Share on other sites
17 minutes ago, timboy666 said:

what is a ssw?

 

16 minutes ago, Ice Man 85 said:

Sudden Stratospheric Warming. I won't pretend to know what that is though

pop over to this thread - 

it will give you all the info you need on a Sudden Stratospheric Warming and all the implications that come with it. :)

that goes for anyone else not sure- it has some excellent explanations in there as to how it affects our weather :good:

  • Like 4
Link to post
Share on other sites
4 minutes ago, karlos1983 said:

Well, a mean chart is just a blend of the model suites members though, not an individual run (to my understanding) So if you’ve got 8 really cold members and 8 reging westerly members there’s probably not going to be a middle ground! One will be wrong and therefore so will the mean! 

My point about the ECM is we don’t get to see without ploughing through that weather.us site viewing each member in isolation what the individual runs are doing. Like that GEFS graph, clearly 2 runs very warm compared to the rest, which will automatically rise the average/mean temperature. Anyway we may derail. 

Absolutely, Karlos. That is the concern when `everything` is not on board. Let`s hope (unless it isn`t cold you are after) that the individual members are outliers that are skewing the mean otherwise we have to take the output at face value.

  • Like 1
Link to post
Share on other sites
10 minutes ago, blizzard81 said:

Great news :) I expect a colder set on the debilt ext ens after hearing this. 

I don't think it will be 'super cold' but hopefully trending in the right direction.  Control looks decent.

  • Like 1
Link to post
Share on other sites
1 hour ago, Snowy L said:

I think the ECM evolution (high building from the Southwest with the undercut coming from the east instead of the west) is more likely. The warming is going to push the Greenland vortex lobe west into central canada over the coming week so I dont see any real pressure coming from the Atlantic. I think the GFS was toying with the Atlantic undercutting and now it is in a bit of a no mans land. Hopefully it gets on board with the ECM in the next few runs.

For entertainment value, here is an illustration of what can be considered highly feasible going forward from the ECM day 10 given expected secondary SSW influence.

No kidding around here although yes, the caveat applies that it's just one possibility among quite a few. Fact is though, if it's ever going to happen, it's when we have the ingredients in place over the next fortnight.

So yes, I have come to accept that a faster height rise to our NE with a major block advancing west starting around Thursday is an outside option now, but I won't complain if the ridge from the mid-Atlantic proves to be the start of such a progression!

FeasibleECMTastyFrom12z9thFeb18.PNG

  • Like 6
Link to post
Share on other sites

An excellent ECM again.  FWIW my view is a delayed Spring until April.  On that basis with my LRF I think we may see a slower burner re this SSW on its effect for us in the U.K. and Ireland re lock in of cold blocked set up.  Very interesting chart watching, GFS back in the mix.....best I grow my peppers and tomatoes I just bought from ‘a shop’ indoors for a while :cold:

Come Sunday there will be many happy cold bunnies in W and NW.....and Cheshire Gap....look out!

BFTP

 

 

Edited by BLAST FROM THE PAST
  • Like 5
Link to post
Share on other sites

The GEFS 12z shows some great wintry potential, think I will be posting a lot more charts similar to these in the coming days..lovely stuff!:cold-emoji:..I know it's deep FI  but it's relevant as it's the range when things could kick off big time..or even sooner if the Ecm is right!!:)

0_384_850tmp.png

11_384_850tmp.png

14_384_850tmp.png

15_384_850tmp.png

17_384_850tmp.png

19_384_850tmp.png

21_384_850tmp.png

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

ECM ensembles are a right old mixed, some really great looking runs and some runs probably would embed a 2-3 week cold spell. Equally there are certainly more than a few runs which do nothing and indeed a decent minority blowthe Atlantic back up again, a few just have a shortwave nightmare, and the rest have a cold set-up of varying degrees (some have a UK high, some have the classic Scandi, some evolve a stunning Greenland-Scandi monster high.)

 

  • Like 2
  • Haha 2
Link to post
Share on other sites
7 minutes ago, Sky Full said:

  image.thumb.png.2152c56a04ef12d4b2344748a9d1e965.png

Just check out the date of that last chart

That's just a bit too close for comfort! 

Further to my last post, not wishing to be taken for a scurrilous ramper, I would add that we currently have nothing like the extent or depth of low uppers over Europe which were evident in 1962/3 and which contributed to the record low temperatures that year.  There is therefore no chance of similarly arctic conditions developing on this occasion.  And I am not related to Michael Fish, either.....

  • Like 1
  • Haha 3
Link to post
Share on other sites
1 minute ago, Sky Full said:

Further to my last post, not wishing to be taken for a scurrilous ramper, I would add that we currently have nothing like the extent or depth of low uppers over Europe which were evident in 1962/3 and which contributed to the record low temperatures that year.  There is therefore no chance of similarly arctic conditions developing on this occasion.  And I am not related to Michael Fish, either.....

Glad you qualified your ramp with some realism  

  • Like 1
Link to post
Share on other sites
Just now, Sky Full said:

Further to my last post, not wishing to be taken for a scurrilous ramper, I would add that we currently have nothing like the extent or depth of low uppers over Europe which were evident in 1962/3 and which contributed to the record low temperatures that year.  There is therefore no chance of similarly arctic conditions developing on this occasion.  And I am not related to Michael Fish, either.....

And to add Greenland had its warmest winter..  The polar vortex over North America remains relentless adding fuel to the jet stream towards the Uk 

vortex.png

vortexx.png

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