Cold hunt - models and chat

[Nick F]

1 minute ago, bluearmy said:

Was thinking about people assuming that a late feb easterly will bring a BFTE .... last feb was exceptional- the ridge got way to our ne which enabled the Siberian cold pool to be advocated a long way sw into nw Europe  ..... and beyond ....

If the ridge can retogress toward Iceland 2nd half of month as per forecast MJO progress implies, and it's a BIG if, then we could perhaps open up the Siberian or arctic  floodgates .. but we need to see whether the TPV co-operates too. 

[Summer Sun]

The ECM mean peaks with a low of around -4 on the 00z 12z was around -6.

The 00z mean is a bit higher from the 11th onwards compared with the 12z yesterday

00z

12z

[Frosty.]

Recently we looked like we were staring down the barrel at a prolonged predominantly mild zonal outlook but the Ecm 00z op / mean are still favouring the scandi high block in the mid range..it goes without saying that I'm praying for a very strong finish to this winter..out like a lion hopefully..I'm seeing potential building blocks!! !!

Edited February 7, 2019 by Frosty.

[Methuselah]

24 minutes ago, shaky said:

Seriously though regardless of that phase 8 MJO BJO whatever you call it!! watch everything flatten out again as if by magic lol!!let the flatten start with the gfs 06z!!!!its a horrible tease from the models especially when the winter has been so boring!!i hope we see the scandi high happen but right now am saying no!!

Morning shaky...the BJO (or Boris Johnson Oscillation) always has both extremes ready for exploitation!

[Nick F]

06z GFS seems to be a lot slower building the ridge N and NE next week compared to ECMWF, but then the model does faff around getting out of phase 6 then slow through phase 7 compared to EC too on the RMM plots, so maybe why it takes an eternity to get the high over Scandi. The slower the ridge building north the more likely it is that it doesn't build where we want it as the TPV has more time to strengthen then flattern out the flow.

[TEITS]

32 minutes ago, Summer Sun said:

The ECM mean peaks with a low of around -4 on the 00z 12z was around -6.

The 00z mean is a bit higher from the 11th onwards compared with the 12z yesterday

00z

 

12z

 

 

At this stage I wouldn't expect much colder temps to be honest.

What is apparent to me is from +168 to +384 we are finally seeing a weakening of the PV over the Canadian side of the Arctic with this transferring over towards Siberia/Asia. This can clearly be seen by looking at the N Hemisphere GEFS mean charts for this period.

My focus remains beyond the Scandi HP, should it develop?

Edited February 7, 2019 by TEITS

[IDO]

Fundamental differences between the GFS and ECM ops as to how they handle the wave train from upstream around D7.

The GFS cuts through the Atlantic trough with the HP cell creating a cut off low near the Azores whilst the ECM pushes the trough towards the Bay of Biscay. Such major variation means the GFS will flatten the pattern as the next wave enters the UK arena, whereas the ECM blocks that cell from interfering with the nascent HLB'ing.

Clearly, the ECM solution gives a greater chance for medium-term cold flows, GFS will need further goes...

[shaky]

Aaaaand the 06z.........YAWN!!!flat again!!on to the 12zs for a more amplified pattern and to then show a more realistic flatter show on tomorrows 00zs!!!

[Chesil View]

5 minutes ago, shaky said:

Aaaaand the 06z.........YAWN!!!flat again!!on to the 12zs for a more amplified pattern and to then show a more realistic flatter show on tomorrows 00zs!!!

But we know the the GFS has a bias towards taking things to far east and flattening the pattern Shaky. So not really to be trusted in a possible Scandi high development scenario. 

Edited February 7, 2019 by Broadmayne blizzard

[Singularity]

The 00z FV3 was amazingly similar to the 00z ECM out to day 10, and went on to retrogress the block via an undercut from the Atlantic and then set up a major unstable cold import from the NE for the final 5 days of Feb.

It's actually a textbook match to what's historically been associated with the MJO crossing P7-P8 at high amplitude in Feb. It's worth noting that P8 shows good correlation to a strongly negative AO-NAO joint pattern regardless of whether there's a downwelling reversal from a SSW. Only downwelling zonal winds ahead of a reversal seem able to counter it - as we were unfortunate enough to see with respect to the middle two weeks of Jan just gone.

[Man With Beard]

Well the clusters are interesting to say the least. Interesting possible slider scenario at T216 on cluster 1. Then, into the D11-D15 period, signs of retrogression to the north. Height anomalies over Europe, while not optimal for cold, are no longer positive. The "winter's over" party may need to be rescheduled!

    

[Methuselah]

And what a chart this one would be - were it to occur anytime between early April and early October! Now, on the other hand, it'd take Davy Crocket, to hunt the easterly, on that!

[edinburgh_1992]

12 minutes ago, shaky said:

Aaaaand the 06z.........YAWN!!!flat again!!on to the 12zs for a more amplified pattern and to then show a more realistic flatter show on tomorrows 00zs!!!

Not a bad ending  to the gfs06. It may take the HP a couple of attempts to push further north, especially at the beginning with a raging PV. Models have consistently been showing a much weaker PV in the long term and that should finally allow the HP to push north without too much difficulty. Let's not forget that we are in February and statistically our chances of seeing blocking are much better than in December for example.

[edinburgh_1992]

That is definitely not an AO+ situation, but a chart full of potential, especially considering what we have been seeing on the models over the past week or so

[TEITS]

GFS Para suggesting snowfall on Sunday across Midlands/N Wales/ E Anglia.

Might cheer up Victor Meldrew i.e Shaky!

[booferking]

"Potential what a word" go for watered down version halfway house uk high and you'll not be to disappointed next week.

[Methuselah]

3 minutes ago, TEITS said:

GFS Para suggesting snowfall on Sunday across Midlands/N Wales/ E Anglia.

Might cheer up Victor Meldrew i.e Shaky!

I don't believe it!

[shaky]

8 minutes ago, TEITS said:

GFS Para suggesting snowfall on Sunday across Midlands/N Wales/ E Anglia.

Might cheer up Victor Meldrew i.e Shaky!

Yup and to make matters worse that gap in accumulations is right over my house in the east midlands!!ridiculous really!!good try though my friend!!

[BlackburnChris]

1 minute ago, shaky said:

Yup and to make matters worse that gap in accumulations is right over my house in the east midlands!!ridiculous really!!good try though my friend!!

It won't even reach Leicester in the end lol . Feel sorry for shakey as I was born in Leicester , and my family have kept me updated on the lack of Snow .

[Kentspur]

31 minutes ago, edinburgh_1992 said:

That is definitely not an AO+ situation, but a chart full of potential, especially considering what we have been seeing on the models over the past week or so

Oh the animals are back! We have a to rest our hopes on. Promising chart that lets hope we build on it on the 12z runs.

[karyo]

It looks like the 6z output is less amplified than the 0z which is not the trend we want. This is noticeable in the ICON and GFS parallel.

[frosty ground]

gfsp Not as amplified following the GFS

[winterof79]

Simply lovely

Come here thurs more

[tight isobar]

25 minutes ago, winterof79 said:

Simply lovely

Come here thurs more

Nice.

For any of you tweet/twitter fans..

Well worth popping on to micheal ventrice site..for hes latest tweet!!!

@-NAO..

its all falling into place now....

And so it should!!

@backloaded

@i'll keep this drum banging!!

Edited February 7, 2019 by tight isobar

[Duane S.]

15 minutes ago, winterof79 said:

Simply lovely

Come here thurs more

Very decent prospects indeed for later in the month.

Clearly the potential for an eventual west based -NAO but I would suggest we get the -NAO in place first, before we start fretting about that!