Model Output Discussion - Into February

[ANYWEATHER]

1 hour ago, Lukesluckybunch said:

so it was only yesterday morning everybody was hyping about the charts what thy ere showing...me included this morning doesnt look anything special to me perhaps a cold or very cold 2/3 days..we need somthing significant to happen in the next couple of weeks before it gets too late..!

I really don't know why there was such hype about the charts ,nothing cold in picticular, too much Hype on SSW . There is no repeat of 2018 this March, if anything we will be looking at plenty of Atlantic weather this Spring....

[Met4Cast]

We're now very close to a technical major SSW at 60N, 10hPa with warming now being recorded at this level. Zonal winds are expected to reverse either later today or tomorrow marking an official major SSW. 

 

[Met4Cast]

The first bout of warming and downwelling looks to be essentially blocked by strong, dominating equatorward flux, this is mostly why I think any mid-Atlantic ridging next week is MJO/trop led rather than SSW led, it's just too fast and there's no real evidence this is down to the SSW now occurring. This is shown well by the stratobserve E-P flux chart.

Later in the month the forecast is for increasing Poleward flux helped by wavebreaking up into the lower stratosphere, this then in turn helps the -ve zonal winds begin to downwell more sufficiently than the first around of warming.

Granted, this is based on GFS det forecasts so it has to be taken with a pinch of salt re: longer term outlook, I wish we had similar charts from the ECM or EPS available but sadly we don't. Based on this though, I still think we're looking at early-mid March for SSW impacts on the troposphere, next weeks mid-Atlantic ridge and likely brief northerly is more of a bonus.

[Lukesluckybunch]

12 minutes ago, ANYWEATHER said:

I really don't know why there was such hype about the charts ,nothing cold in picticular, too much Hype on SSW . There is no repeat of 2018 this March, if anything we will be looking at plenty of Atlantic weather this Spring....

it always happens people ..or we alll go over the top..we are not in the right location..central and eastern europe will be the boundary for this cold weather

[mbrothers]

1 minute ago, Lukesluckybunch said:

it always happens people ..or we alll go over the top..we are not in the right location..central and eastern europe will be the boundary for this cold weather

Tbf you’re doing again but the other way. Has no one got an ounce of patience before reacting anymore?

[Met4Cast]

Just now, mbrothers said:

Tbf you’re doing again but the other way. Has no one got an ounce of patience before reacting anymore?

Welcome to the Netweather model output thread.. 

[Lukesluckybunch]

Just now, mbrothers said:

Tbf you’re doing again but the other way. Has no one got an ounce of patience before reacting anymore?

well i just go on previous expericences and generally what i see most winters...that area seems to be the western extent of very cold weather,even places like germany and poland arent quite as cold as they used to be.

[ANYWEATHER]

6 minutes ago, Lukesluckybunch said:

it always happens people ..or we alll go over the top..we are not in the right location..central and eastern europe will be the boundary for this cold weather

It's not about being in the right location. Our tiny island of Great Britain, only covers 0.01%  of the Earth's surface. We do get a lot of weather of all types but not what most of us wish for!

[Lukesluckybunch]

Just now, ANYWEATHER said:

It's not about being in the right location. Our tiny island of Great Britain, only covers 0.01%  of the Earth's surface. We do get a lot of weather of all types but not what most of us wish for!

yes with UK being so small,we need a lot of things to go right for cold here!

[Met4Cast]

8 minutes ago, Lukesluckybunch said:

yes with UK being so small,we need a lot of things to go right for cold here!

And currently there’s nothing to suggest it’s going wrong, or indeed “right”. 

The current evolution is going largely as expected for a number of days now, i’m not sure why there has been hype re: next week as that always looked transient as myself & a few others have been suggesting. 

Indeed, early-mid March was always the target period for SSW impacts, what they will be remains to be seen of course so it’s going to be a waiting game. Unfortunately unlike 2018 which saw a rapid tropospheric response to the (I believe?) record breaking SSW, this time around the atmospheric configuration & the type of SSW (displacement) favours a much slower, more drawn out response. I know that doesn’t typically sit well with some on the forum wishing for instant response gratification but that is the current reality of the situation.  

So.. for now, distance yourself from any preferences re: cold weather & watch as one of the most dramatic & in my eyes interesting events on our planet unfolds. (the SSW)

Edited February 15, 2023 by Met4Cast

[Lukesluckybunch]

2 minutes ago, Met4Cast said:

And currently there’s nothing to suggest it’s going wrong, or indeed “right”. 

The current evolution is going largely as expected for a number of days now, i’m not sure why there has been hype re: next week as that always looked transient as myself & a few others have been suggesting. 

Indeed, early-mid March was always the target period for SSW impacts, what they will be remains to be seen of course so it’s going to be a waiting game. Unfortunately unlike 2018 which saw a rapid tropospheric response to the (I believe?) record breaking SSW, this time around the atmospheric configuration & the type of SSW (displacement) favours a much slower, more drawn out response. I know that doesn’t typically sit well with some on the forum wishing for instant response gratification but that is the current reality of the situation.  

So.. distance yourself from your preferences re: cold weather & watch as one of the most dramatic & in my eyes interesting events on our planet unfolds. (the SSW)

well i like to keep it simple and i dont pretend i know as much as you guys..but i like your posts met4cast because you say it how it is.

Edited February 15, 2023 by Lukesluckybunch
spelling

[bluearmy]

39 minutes ago, ANYWEATHER said:

I really don't know why there was such hype about the charts ,nothing cold in picticular, too much Hype on SSW . There is no repeat of 2018 this March, if anything we will be looking at plenty of Atlantic weather this Spring....

 

26 minutes ago, Lukesluckybunch said:

it always happens people ..or we alll go over the top..we are not in the right location..central and eastern europe will be the boundary for this cold weather

We were waiting to see what changes occurred once the reversal at the very top of the strat was in the starting data 

and we saw more amplification modelled for next week across the ops - ignoring our sector of the east Atlantic and looking at the NH 

so that was notable 

unfortunately, this hemispheric propensity to amplify tied in with an existing propensity for a MAR next week so we saw runs where the n pacific ridge punched into the polar field along with the MAR.    It was noted yesterday morning that the runs may have been too sensitive to slowing down the trop zonal flow and we should wait for the 12z etc etc 

id give it another day or so yet before drawing conclusions 

Edited February 15, 2023 by bluearmy

[Lukesluckybunch]

6z looking nice at 162 heights starting to push into greenland

[Battleground Snow]

1 minute ago, Lukesluckybunch said:

6z looking nice at 162 heights starting to push into greenland

Yeh better a ridge going up. Probably still transient in nature 

One thing that confuses me is that charts day 7 onwards that show cold blocked scenarios are always treated with extreme caution, but charts that show something else are almost treated as being 100% correct.

Obviously climatology favours milder conditions for the UK, but surely at long time scales we are just watching the models for trends, especially just after a SSW 

[nick sussex]

After a lot of searching I’ve found more strat diagnostics and these show the actual latitude . Courtesy of NASA  and GEOS.

These do show zonal wind and latitude as opposed to just the blunt tool of simply the layers . And loads of other data.

You need to type NASA GSFC Stratosphere into your search engine.

 

 

[feb1991blizzard]

you can now see on the output the tropics are not configured in a way for HLB, the rounded high just not gaining enough latitude is the giveway, the SSW will not deliver in feb - March - different story however.

[jellybaby1969]

2 hours ago, Lukesluckybunch said:

so it was only yesterday morning everybody was hyping about the charts what thy ere showing...me included this morning doesnt look anything special to me perhaps a cold or very cold 2/3 days..we need somthing significant to happen in the next couple of weeks before it gets too late..!

Luke you should read your post....models do not have a handle on the effect of SSW..until we get some consistency and cross model agreement then we can think about winter woolies or t shirts n shorts.

[DJ Fart]

47 minutes ago, mbrothers said:

Tbf you’re doing again but the other way. Has no one got an ounce of patience before reacting anymore?

There are reasons why the ignore function is your friend on here. Makes a much better experience when you curate it to how you want.

[Ali1977]

Whilst the hp isn’t heading north as we’d like, we do have a better set up over Spain so it is a better run on that front, the lp over Spain is keeping the Hp from sinking - so it may be quite a chilly event at the surface !! 

 
Just a waiting game for now ref the SSW, although there may be a transiting front from the north next Thursday that could bring some snow to hills and down the east, albeit probably more of a damp affair !! 

Edited February 15, 2023 by Ali1977

[IDO]

9 minutes ago, Battleground Snow said:

Yeh better a ridge going up. Probably still transient in nature 

One thing that confuses me is that charts day 7 onwards that show cold blocked scenarios are always treated with extreme caution, but charts that show something else are almost treated as being 100% correct.

Obviously climatology favours milder conditions for the UK, but surely at long time scales we are just watching the models for trends, especially just after a SSW 

I think what we are seeing currently and as we advance is a benign NH profile with the tPV mobility dictating the mid and low-latitude design. So the ebb and flow of the tPV in the Pacific region allows the omnipresent Pacific high to bell north occasionally. There does not appear to be any forcing, which applies to the Atlantic/UK high. That is not a forced ridge, just the Azores high displaced further north due to the wax and wane of the tPV to the north.

Post D8, we see the tPV lobe to our NE start migrating to the west to our north, which means that the UK high is restricted to forcing into higher latitudes. This seems a robust signal and is why GFS is consistent with the UK high. It has happened several times this winter so we can use it as a guide. For me, we are relying on the impact of an SSW for further chances of a cold spell.

The caveat is that all bets are off once the models start responding to the downwelling, and it can all change quickly then. But we need that to be a consistent signal rather than just one run simulating that possibility. Until the SSW response, we are in this likely quasi-blocked Atlantic/UK high again.

D12 GFS 06z:

[feb1991blizzard]

now watch the rest of the run in early March and see what happens.

[MJB]

Getting there

[Ali1977]

2 minutes ago, feb1991blizzard said:

now watch the rest of the run in early March and see what happens.

Compared to the last run the cold is definitely in a better place around T336

[alexisj9]

2 hours ago, bluearmy said:

Doesn’t that say mild, average wetness and average windyness as being the most likely outcome ?? 
 

All three are wrong for this corner anyway, it's been average dry and not much wind at all.

[Starsail]

1 hour ago, Met4Cast said:

We're now very close to a technical major SSW at 60N, 10hPa with warming now being recorded at this level. Zonal winds are expected to reverse either later today or tomorrow marking an official major SSW. 

 

Houston we have lift off. If next weeks mid atlantic ridge is being modelled purely on mjo/ trop led factors then I wonder if the models may start to adjust as live data from the SSW starts to feed into starting conditions?