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FI Charts (+T120 onwards) Autumn/Winter 2015 - see Mod Note post #1

2456715

Comments

  • Registered Users, Registered Users 2 Posts: 11,134 ✭✭✭✭maquiladora


    Stormy conditions for the west on Friday on the 12Z GFS but the UKMO and ECM don't develop the low, so it's FI stuff even though its only 96 hours.


  • Registered Users, Registered Users 2 Posts: 11,134 ✭✭✭✭maquiladora


    :P

    gensnh-16-1-348_rih7.png


  • Registered Users, Registered Users 2 Posts: 11,134 ✭✭✭✭maquiladora


    Once again, GFS probably overdoing it with another low.

    jiTTfWO.gif


  • Registered Users, Registered Users 2 Posts: 17,797 ✭✭✭✭hatrickpatrick


    :P

    gensnh-16-1-348_rih7.png

    This is pretty much the holy grail of wintry weather :D


  • Registered Users, Registered Users 2 Posts: 11,134 ✭✭✭✭maquiladora


    This is pretty much the holy grail of wintry weather :D

    Nah I think that would be closer to this. ;)

    archives-1933-2-24-12-0.png


  • Registered Users, Registered Users 2 Posts: 3,171 ✭✭✭Rebelbrowser


    Nah I think that would be closer to this. ;)

    archives-1933-2-24-12-0.png

    Apologies if this is the wrong thread for this and/or if its too much of an ask. I wonder though could one of the more knowledgeable contributors here explain what it is about Maq's chart above that makes it so wintry. Maq having identified it as wintry I believe I understand it (if I am right its cold air sourced in Russia feeding into a low pressure system to our south leading to snowmaggedon) - but if I was just shown that chart in the abstract I'm not sure if I'd have come to the same conclusion. I generally need to look at (upper) temp charts also just to confirm my read of a chart is correct. I can't be the only one either I also suspect.

    Just a thought on educating us masses with winter coming....


  • Registered Users, Registered Users 2 Posts: 5,068 ✭✭✭Iancar29


    Apologies if this is the wrong thread for this and/or if its too much of an ask. I wonder though could one of the more knowledgeable contributors here explain what it is about Maq's chart above that makes it so wintry. Maq having identified it as wintry I believe I understand it (if I am right its cold air sourced in Russia feeding into a low pressure system to our south leading to snowmaggedon) - but if I was just shown that chart in the abstract I'm not sure if I'd have come to the same conclusion. I generally need to look at (upper) temp charts also just to confirm my read of a chart is correct. I can't be the only one either I also suspect.

    Just a thought on educating us masses with winter coming....

    Yeah ur pretty much correct. There we have cold air sourced from a cold continent, a low pressure undercutting a high to bring strong instability ( heavy snow showers) and a blocked atlantic to keep the dominant wind easterly in direction.


  • Registered Users, Registered Users 2 Posts: 11,134 ✭✭✭✭maquiladora


    Iancar29 wrote: »
    Yeah ur pretty much correct. There we have cold air sourced from a cold continent, a low pressure undercutting a high to bring strong instability ( heavy snow showers) and a blocked atlantic to keep the dominant wind easterly in direction.

    Indeed, blocked Atlantic, easterly flow, cold pool over Ireland and most important of all the low delivering copious amounts of frontal snow with strong winds. Drifts over 300cm.

    http://www.irishidentity.com/extras/weather/stories/bigsnow.htm


  • Closed Accounts Posts: 4,816 ✭✭✭Baggy Trousers




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  • Registered Users, Registered Users 2 Posts: 5,068 ✭✭✭Iancar29


    I'll just leave these here... :pac:

    gfs-0-348_szx9.png
    gfs-1-348_gfu5.png


  • Registered Users, Registered Users 2 Posts: 6,188 ✭✭✭Elmer Blooker


    Iancar29 wrote: »
    I'll just leave these here... :pac:
    Glorious chart but I hope this doesn't happen, I would take another six weeks of this very mild weather and wait for a proper winter rather than an early false alarm! Too early for my liking.


  • Registered Users, Registered Users 2 Posts: 13,679 ✭✭✭✭sryanbruen


    Iancar29 wrote: »
    I'll just leave these here... :pac:

    gfs-0-348_szx9.png
    gfs-1-348_gfu5.png

    If only this actually happened! But no it will sadly not :(


  • Registered Users Posts: 788 ✭✭✭Snowbiee21


    sryanbruen wrote: »
    If only this actually happened! But no it will sadly not :(

    What is this chart saying its bringing?


  • Registered Users, Registered Users 2 Posts: 13,679 ✭✭✭✭sryanbruen


    Snowbiee21 wrote: »
    What is this chart saying its bringing?

    Very cold temperatures on Thursday, November 19th.


  • Registered Users Posts: 788 ✭✭✭Snowbiee21


    sryanbruen wrote: »
    Very cold temperatures on Thursday, November 19th.

    Any precip?


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  • Registered Users, Registered Users 2 Posts: 13,679 ✭✭✭✭sryanbruen


    Snowbiee21 wrote: »
    Any precip?

    No as the pressure is relatively high


  • Registered Users Posts: 788 ✭✭✭Snowbiee21


    sryanbruen wrote: »
    No as the pressure is relatively high
    Hopefully a bit of wintry precip over these few cold days


  • Registered Users, Registered Users 2 Posts: 11,134 ✭✭✭✭maquiladora


    Snowbiee21 wrote: »
    Hopefully a bit of wintry precip over these few cold days

    It's 348 hours out, which is in the extremely unreliable time-frame. FI stands for Fantasy Island. These charts are just for fun until you get till around 148-168 hours out and even then it can completely change quite easily.


  • Registered Users, Registered Users 2 Posts: 13,679 ✭✭✭✭sryanbruen


    It's 348 hours out, which is in the extremely unreliable time-frame. FI stands for Fantasy Island. These charts are just for fun until you get till around 148-168 hours out and even then it can completely change quite easily.

    Like the end of the world in 2012 :D


  • Registered Users, Registered Users 2 Posts: 17,797 ✭✭✭✭hatrickpatrick


    sryanbruen wrote: »
    Like the end of the world in 2012 :D

    I don't think the Mayans were taking leap years into account, so they may have only been out by a few years :pac:


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  • Registered Users, Registered Users 2 Posts: 13,679 ✭✭✭✭sryanbruen


    I don't think the Mayans were taking leap years into account, so they may have only been out by a few years :pac:

    It was a joke.


  • Registered Users, Registered Users 2 Posts: 11,134 ✭✭✭✭maquiladora


    Another fun deep FI from the 18Z GFS.


  • Registered Users, Registered Users 2 Posts: 17,797 ✭✭✭✭hatrickpatrick


    sryanbruen wrote: »
    It was a joke.

    Whilst my post was entirely serious and sincere? ;)


  • Registered Users, Registered Users 2 Posts: 17,797 ✭✭✭✭hatrickpatrick


    Boy oh boy :D

    367631.png

    EDIT:

    Just had a look through the GFS ensembles and made a few notes. Being honest I'm a bit lazy tonight so I only looked at 850hpa temperatures, didn't look at pressure or precipitation. Will do that when and if these good scenarios move out of FI and become serious possibilities.

    There are 20 variations in the ensemble. Most of the runs which show cold towards the end of November unfortunately also show a large lobe of heat building from the equatorial Atlantic towards Greenland, and this then being swept Eastwards by the jet stream towards us. I've made a list of the ensembles which actually look promising:

    3, 6, 10,and 11 are the best ones.

    6 in particular is the absolute holy grail. with very cold uppers which persist for several days at the end of the run, and beyond.

    2, 7, and 19 are good, but look like they're getting ready to dissipate (about to warm up) at +384 hours, beyond which the models don't run so I could be wrong about this. Just seems like that's the way it's going for Ireland in those runs, you can see warmth spreading nearby.

    4, 15, and 17 are the opposite of the above - no sub-zero temperatures on these charts, but they look towards the tail end of the run like the cold is about to envelope Ireland.

    How I'm judging a good and bad run is fairly simple - whether the zero degree isotherm is above, below, or splitting Ireland. We need that isotherm to the south of us before we can even talk about snow persisting on the ground. Obviously the truly epic runs (variation +6 is amazing, check it out in case it disappears on the next run :D) have temperatures of -4 to -8 on them, but at least getting the 0 isotherm properly below Ireland is a start, because it implies that the jet stream has moved to the south which can potentially allow cold northern air to sweep downwards.

    Back in 2010, what happened was that the jet stream formed "waves", so that it swung sharply to the North just before Greenland, peaked there, and then was rammed sharply South where it remained until it had passed Ireland. What I don't yet understand, and somebody feel free to educate me if they know this, is the chicken-and-egg status of the jet stream moving and the blocking high which formed over Greenland that November. In other words, did the jet stream shift because the block forced it to, or did the block form because of the jet stream's unusual behaviour?


  • Registered Users Posts: 788 ✭✭✭Snowbiee21


    Boy oh boy :D

    367631.png

    EDIT:

    Just had a look through the GFS ensembles and made a few notes. Being honest I'm a bit lazy tonight so I only looked at 850hpa temperatures, didn't look at pressure or precipitation. Will do that when and if these good scenarios move out of FI and become serious possibilities.

    There are 20 variations in the ensemble. Most of the runs which show cold towards the end of November unfortunately also show a large lobe of heat building from the equatorial Atlantic towards Greenland, and this then being swept Eastwards by the jet stream towards us. I've made a list of the ensembles which actually look promising:

    3, 6, 10,and 11 are the best ones.

    6 in particular is the absolute holy grail. with very cold uppers which persist for several days at the end of the run, and beyond.

    2, 7, and 19 are good, but look like they're getting ready to dissipate (about to warm up) at +384 hours, beyond which the models don't run so I could be wrong about this. Just seems like that's the way it's going for Ireland in those runs, you can see warmth spreading nearby.

    4, 15, and 17 are the opposite of the above - no sub-zero temperatures on these charts, but they look towards the tail end of the run like the cold is about to envelope Ireland.

    How I'm judging a good and bad run is fairly simple - whether the zero degree isotherm is above, below, or splitting Ireland. We need that isotherm to the south of us before we can even talk about snow persisting on the ground. Obviously the truly epic runs (variation +6 is amazing, check it out in case it disappears on the next run :D) have temperatures of -4 to -8 on them, but at least getting the 0 isotherm properly below Ireland is a start, because it implies that the jet stream has moved to the south which can potentially allow cold northern air to sweep downwards.

    Back in 2010, what happened was that the jet stream formed "waves", so that it swung sharply to the North just before Greenland, peaked there, and then was rammed sharply South where it remained until it had passed Ireland. What I don't yet understand, and somebody feel free to educate me if they know this, is the chicken-and-egg status of the jet stream moving and the blocking high which formed over Greenland that November. In other words, did the jet stream shift because the block forced it to, or did the block form because of the jet stream's unusual behaviour?
    . Wonder what precip it will bring, hopefully some of the white stuff 😊😏😏😏


  • Registered Users, Registered Users 2 Posts: 5,068 ✭✭✭Iancar29


    Its gone on the 12z lads... good oul FI


  • Registered Users Posts: 788 ✭✭✭Snowbiee21


    Iancar29 wrote: »
    Its gone on the 12z lads... good oul FI

    Somebody attach a model or whatever


  • Registered Users, Registered Users 2 Posts: 11,134 ✭✭✭✭maquiladora


    Iancar29 wrote: »
    Its gone on the 12z lads... good oul FI

    When in doubt....GEFS

    gensnh-10-1-384_srq2.png


  • Registered Users, Registered Users 2 Posts: 5,068 ✭✭✭Iancar29


    Yep, back again on the Operational 06z
    gfs-0-276_ppu2.png


  • Registered Users, Registered Users 2 Posts: 11,134 ✭✭✭✭maquiladora


    Some lovely looking blocking out in far FI among the GEFS.

    gensnh-10-1-360_qxz1.png


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  • Registered Users, Registered Users 2 Posts: 17,797 ✭✭✭✭hatrickpatrick


    Snowbiee21 wrote: »
    . Wonder what precip it will bring, hopefully some of the white stuff 😊😏😏😏

    Shaded white line areas are snow ;)


  • Registered Users, Registered Users 2 Posts: 17,797 ✭✭✭✭hatrickpatrick


    High pressure is now trying to edge its way up to Greenland near the ends of the main GFS and ECM runs. It's having only varying measures of success and is generally being swept aside fairly quickly, but the fact that charts with such a distorted polar vortex are appearing this early in November is a good sign indeed. Believe ;)


  • Registered Users, Registered Users 2 Posts: 5,068 ✭✭✭Iancar29


    Some lovely looking blocking out in far FI among the GEFS.

    gensnh-10-1-360_qxz1.png

    r9TptTb.gif


  • Registered Users, Registered Users 2 Posts: 5,068 ✭✭✭Iancar29


    10 days out.... it WILL change.. but nice to see! :)

    367753.png


  • Registered Users Posts: 788 ✭✭✭Snowbiee21


    Shaded white line areas are snow ;)

    And where are these lines can i ask


  • Registered Users, Registered Users 2 Posts: 2,855 ✭✭✭Nabber


    Pink on Iancars chart = snow....

    Ramping early November..... It's almost as beautiful as the snow.....


  • Registered Users, Registered Users 2 Posts: 11,134 ✭✭✭✭maquiladora


    gensnh-18-1-384_icb6.png
    gensnh-10-1-384_vci6.png


  • Registered Users Posts: 603 ✭✭✭Captain Snow


    November 2010 repeat ?

    vqf3YN.png


    22 November 2010

    3boEIS.gif


  • Registered Users, Registered Users 2 Posts: 17,797 ✭✭✭✭hatrickpatrick


    November 2010 repeat ?

    We can dream :D

    This is shaping up to be the most interesting November in years. Last year and the year before, even FI didn't hint at anything like this. :D

    Where the hell is Redsunset with his SSW tracking?


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  • Registered Users Posts: 603 ✭✭✭Captain Snow


    We can dream :D

    This is shaping up to be the most interesting November in years. Last year and the year before, even FI didn't hint at anything like this. :D

    Where the hell is Redsunset with his SSW tracking?


    https://forum.netweather.tv/topic/84231-stratosphere-temperature-watch-20152016/


  • Registered Users, Registered Users 2 Posts: 11,134 ✭✭✭✭maquiladora


    Looks like this will be the end of wintry FI charts for the foreseeable future again.


  • Registered Users Posts: 788 ✭✭✭Snowbiee21


    Looks like this will be the end of wintry FI charts for the foreseeable future again.

    Why why


  • Registered Users, Registered Users 2 Posts: 11,134 ✭✭✭✭maquiladora


    cfs-0-930_idz1.png
    deflated-santa.jpg


  • Registered Users Posts: 788 ✭✭✭Snowbiee21


    cfs-0-930_idz1.png
    deflated-santa.jpg

    Warm or cold


  • Registered Users, Registered Users 2 Posts: 2,689 ✭✭✭Darwin


    UK met office is not too hopeful of cold in the immediate future, westerly zonality all the way for the immediate outlook (possibly all the way to January) with the odd Polar Maritime incursion.


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  • Registered Users, Registered Users 2 Posts: 1,729 ✭✭✭martinsvi


    cfs-0-930_idz1.png

    that pressure gradient - is that a hurricane? 60+mb difference between the eye and the outer circle, uh-oh..


  • Registered Users, Registered Users 2 Posts: 1,513 ✭✭✭Reckless Abandonment


    Snowbiee21 wrote: »
    Warm or cold

    Cold. As you'll probably be missing your roof .


  • Registered Users, Registered Users 2 Posts: 11,134 ✭✭✭✭maquiladora


    martinsvi wrote: »
    that pressure gradient - is that a hurricane? 60+mb difference between the eye and the outer circle, uh-oh..

    It's the CFS and 900+ hours away. It's not going to happen. ;)


  • Registered Users, Registered Users 2 Posts: 5,068 ✭✭✭Iancar29


    Cold. As you'll probably be missing your roof .

    hqdefault.jpg
    martinsvi wrote: »
    that pressure gradient - is that a hurricane? 60+mb difference between the eye and the outer circle, uh-oh..
    It's the CFS and 900+ hours away. It's not going to happen. ;)

    And it wouldn't be a hurricane anyways as its a cold core system aka extra tropical cyclone. :)


  • Registered Users, Registered Users 2 Posts: 3,171 ✭✭✭Rebelbrowser


    I know the CFS is very long range but thought I'd share this extract from a post which I've already posted in the White Christmas thread..


    ".... Just as a final observation, the CFS shows it being consistently cool (cold at times) from around 10th Jan to mid Feb with 850 hpa uppers at -2 or below at virtually all times and plenty of "pink" all over much of Europe. I attach a typical enough chart from the period....

    16012600_0900.gif


    Plenty of interest to come accordingly....."


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