nav[aria-label="Primary Navigation"] { padding: 0; & ul { list-style: none; width: 100%; display: flex; flex-direction: row; justify-content: start; align-items: start; gap: 30px; padding: 0; & li { margin: 0; } & ul li { list-style: none; } } }

Child Item

FI Charts (T120+ onwards) Winter 2018 READ MOD NOTE IN FIRST POST

Meteorite58

Mod Note
This thread is for posting/discussing/analysing FI CHARTS ONLY i.e. Charts in the unreliable time frame, generally +T120 onwards

If your post does not specifically relate to an FI chart then it doesn't belong here - Off topic posts will be moved

Thanks

Find more posts tagged with

Quick Links

Comments

torres9kop

Could Cheltenham races mid March be jeopardised by this oncoming snowmageddon?

sryanbruen

torres9kop wrote: »

Could Cheltenham races mid March be jeopardised by this oncoming snowmageddon?

Nobody's expecting snowmageddon :P but if everything was setup right, I don't see why not.

GFS 12z eventually gets to easterly but overall, it is more inline with the GFS 00z and is a downgrade on the GFS 06z. Expect lots more flip flopping.

The 18th continues to be the day when the high pressure builds from the south meanwhile - this is now out of FI range.

pistolpetes11

torres9kop wrote: »

Could Cheltenham races mid March be jeopardised by this oncoming snowmageddon?

In all honesty we don't know what the weather will be at next week , so nearly a month away , we wouldn't have a clue

Snowbiee21

Found this very interesting !

sryanbruen

GFS 12z control run is a bit of a mess but in general, it has us in a settled pattern.

RobertKK

On BBC1, the met office said that we are entering a milder period but there are signs that the end of February will be very very cold.

BLIZZARD7

ECM about to show us a very nice FI I would think - +144hrs chart looking good with heights punching north.

BLIZZARD7

Strange run, holds low heights over greenland/Iceland which seems somewhat unlikely to me. The transition from +144hrs to +168hrs to +192 hours doesn't look quite right either, it's showing too much strength in the PV over the greenland area.

More chopping and changing to come, I suspect the models haven't a clue how to handle these sustained assaults on the stratosphere. I'm thinking we will see big improvements in the +120 to +144hrs timeframe very soon.

nacho libre

RobertKK wrote: »

On BBC1, the met office said that we are entering a milder period but there are signs that the end of February will be very very cold.

It's not the UK met office that provide the weather anymore. The BBC still use them for weather warnings, though.

The GFS takes its time in bringing an easterly, then has it going away after a few days. Is this the usual GFS habit of been too quick with a breakdown? It reminds me of back in late February 2013, the GFS twice signalled an end to blocking but the blocking persisted . I hope it will prove to be the same this time. The UK Met office have it persisting well into March

M.T. Cranium

Looks like Ireland is about to be swallowed by the whale in this map

nacho libre

BLIZZARD7 wrote: »

Strange run, holds low heights over greenland/Iceland which seems somewhat unlikely to me. The transition from +144hrs to +168hrs to +192 hours doesn't look quite right either, it's showing too much strength in the PV over the greenland area.

More chopping and changing to come, I suspect the models haven't a clue how to handle these sustained assaults on the stratosphere. I'm thinking we will see big improvements in the +120 to +144hrs timeframe very soon.

Well let's hope so, because it would be a real sickner with a split vortex and then a seconday warming if that is the actual outcome. I will remain optimistic given the UK Met Office outlook. If that suddenly changes then it will probably be game over.

sryanbruen

sryanbruen wrote: »

GFS 12z control run is a bit of a mess but in general, it has us in a settled pattern.

In fact, this run reminds me an awful lot of the second half of February 2013. That was an unusually long, quiet spell of weather with rather cool temperatures but nothing spectacular and some frosts with the best of sunshine in the west. That was the same year the January 2013 SSW took place and then March arrived.... we all know what happened there.

Goes back to me saying, get the high pressure in first. All historical cold spells begin somewhere.

George Sunsnow

BLIZZARD7 wrote: »

Strange run, holds low heights over greenland/Iceland which seems somewhat unlikely to me. The transition from +144hrs to +168hrs to +192 hours doesn't look quite right either, it's showing too much strength in the PV over the greenland area.

More chopping and changing to come, I suspect the models haven't a clue how to handle these sustained assaults on the stratosphere. I'm thinking we will see big improvements in the +120 to +144hrs timeframe very soon.

Not strange just fantasy island
It’s got it right up to the point the high sits on us
After that it’s like FI on any run any night of the week,even when it shows what you want,totally unreliable

BLIZZARD7

George Sunsnow wrote: »

Not strange just fantasy island
It’s got it right up to the point the high sits on us
After that it’s like FI on any run any night of the week,even when it shows what you want,totally unreliable

I just find it odd the way it flattens a ridge building northwards with lots of WAA heading straight towards the pole with such ease and then defaults to the PV over greenland, it's like someone flicked a switch at +168hrs and the ECM became unaware of strat situation. Not an impossible outcome by any means but I would say improbable at this point given where the warmings are occurring. Goes against the MJO analogues too.

George Sunsnow

It’s a problem with 24hr frames,you just don’t see the detail (albeit fantasy detail)

you get only a quarter of the information that’s on the gfs and 24hours is a long time in weather
That wouldn’t mean what it’s done isn’t plausible
It’s as likely as anything else it throws up

That’s the thing about model watching and forecasting
There’s a lot of has this happened before about it and a lot of is there cross model agreement
Lack of the latter means guessing at a blend of what the computer programmes are saying

In my opinion the high cannot head south when the cold is there and lows further below
If it’s going to retrogress it will want to follow the waa or head for another high
Heading northeast in this run it actually does that in aiming for northern Russia/Siberia and a high there somewhere

Regardless ,Midweek next week is when we will know what’s what
If it’s a March 2013,it can take a 100 yard dash off a 50 yard pier as far as I’m concerned

nacho libre

BLIZZARD7 wrote: »

I just find it odd the way it flattens a ridge building northwards with lots of WAA heading straight towards the pole with such ease and then defaults to the PV over greenland, it's like someone flicked a switch at +168hrs and the ECM became unaware of strat situation. Not an impossible outcome by any means but I would say improbable at this point given where the warmings are occurring. Goes against the MJO analogues too.

Unless it foresees what other models don't-namely the vortex somehow remaining robust enough to stay where it is. As you say it's improbable, but not impossible. I did notice that some of strat experts over on netweather were cautioning this might happen. We just have to hope the ECM hasn't being able to get a proper handling on the effect of the second warming. With this in mind the ECM has been poor enough this year , so that gives me some hope that it is struggling to get a handle on this complicated setup that is ongoing.

typhoony

an SSW event usually results in the amplification of the jet, correct if I'm wrong but we more often than not end on the wrong side of the amplification i.e the warm side whereas the North East of the U.S gets frigid weather

sryanbruen

typhoony wrote: »

an SSW event usually results in the amplification of the jet, correct if I'm wrong but we more often than not end on the wrong side of the amplification i.e the warm side whereas the North East of the U.S gets frigid weather

2/3 (66%) SSW events work in our favour for cold.

BLIZZARD7

Have to disagree @george sunsnow, it's not as likely as likely as any other output as its not likely we will see a strengthening vortex over greenland at all. Never mind the SSW, later into February is when it normally starts to weaken, on top of such a major SSW I just cannot see that happening. This isn't anything like our normal setup.

'The strat. vortex is currently weaker than all other years in the ERA interim record!!!
The zonal mean zonal wind at 10 hPa 60N is today (GFS analysis): -20.1 m/s
Weakest zonal wind at 10 hPa 60N in ERA interim record for todays date is: -13.0 m/s 1987'

http://weatheriscool.com

I'm not saying we will definitely have very cold weather however it's not a likely option that our chances get scuppered through low heights over the greenland area*

144-192hrs however unreliable is still modeled in the high resolution part of the run.

*there was a slight uptick in solar activity, we don't want to see this pick up anymore and I really hope this hasn't thrown a spanner in the works.

esposito

Just watched the latest update on bbc news 24 there. Saying a fair chance of cold easterly winds end of next week. Lets’ just hope the cold floods far enough west over the Irish Sea to us.

nacho libre

BLIZZARD7 wrote: »

*there was a slight uptick in solar activity, we don't want to see this pick up anymore and I really hope this hasn't thrown a spanner in the works.

I do recall Stuart Rampling blaming this for the infamous easterly that never was in December 2012. Is that really plausible? Can it override all other signals? I mean we are due to see warm air over the eastern usa and parts of Canada which usually correlates with colder outbreaks over the UK and Ireland. Everything seems to favour a cold outbreak, rather than a continuation of the current pattern.

Rebelbrowser

18z gfs is back on track....

George Sunsnow

BLIZZARD7 wrote: »

Have to disagree @george sunsnow, it's not as likely as likely as any other output as its not likely we will see a strengthening vortex over greenland at all. Never mind the SSW, later into February is when it normally starts to weaken, on top of such a major SSW I just cannot see that happening. This isn't anything like our normal setup.

'The strat. vortex is currently weaker than all other years in the ERA interim record!!!
The zonal mean zonal wind at 10 hPa 60N is today (GFS analysis): -20.1 m/s
Weakest zonal wind at 10 hPa 60N in ERA interim record for todays date is: -13.0 m/s 1987'

http://weatheriscool.com

I'm not saying we will definitely have very cold weather however it's not a likely option that our chances get scuppered through low heights over the greenland area*

144-192hrs however unreliable is still modeled in the high resolution part of the run.

*there was a slight uptick in solar activity, we don't want to see this pick up anymore and I really hope this hasn't thrown a spanner in the works.

I’m not sure what you’re disagree’ing with

Experts at the UKMO think easterlies are likely
So they don’t believe output like tonight’s ECM is likely
I don’t either and didn’t say I did
What I said was it’s not an impossible outcome out of the range of possibilities that our high would board a return Siberian express
Obviously it’s unlikely because a Greenland low of the depth modeled doesn’t seem what you’d expect, Ergo our high shouldn’t be looking at Russia somewhere as a friendlier direction to move
But if you do have a low up there,prepare to be goosed

Incidentally high resolution counts for little if it’s inaccurate at that range

sryanbruen

Classic Pub Run :pac:, think it went a bit too much on the drinking tonight.

sryanbruen

GFS 18z control run.

sryanbruen

GFS 18z ensemble means, still barely any change in them except rather colder.

BLIZZARD7

Well the 00z GFS op run wants to bring us a proper Blizzard out in FI -

gfs-1-288.png?0

BLIZZARD7

George Sunsnow wrote: »

I’m not sure what you’re disagree’ing with

'you get only a quarter of the information that’s on the gfs and 24hours is a long time in weather
That wouldn’t mean what it’s done isn’t plausible
It’s as likely as anything else it throws up'

I just disagree that the ECM 12z output is as likely as anything else it has thrown up, it looked confused to me.

Anyway it doesn't matter, as you say in the other thread, over analyzing this output run to run is futile at this range - better to stick to ensemble means for the general pattern and check everything is on track every day or two.

Gaoth Laidir

Have a look on www.weather.us and you can get the ECM in 3-6-hourly steps. The same on www.vedur.is

KingdomRushed

Interesting, GFS has been steady as a rock bringing in a cold easterly with almost universal ensemble support in the 192 hours + timeframe.

Caution needed through, ECM is not half as bullish.

In recent winters we have seen models show these easterlies with full ensemble support time and time again in FI only to evaporate.