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FI Charts ( T120+ onwards) Autumn 2020 **READ MOD NOTE IN FIRST POST**

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  • Moderators, Science, Health & Environment Moderators Posts: 16,676 Mod ✭✭✭✭Gonzo


    pauldry wrote: »
    In Sligo weathers been great this year bar first 2 weeks of July which were dark and cold.

    October looks like it will be our worst weather since start of March. A cold and wet one.
    However it could always get mild or warm mid month which sometimes happens

    Rainfall has generally been normal or below here since Mid March.

    October is going to have to be fairly brutal to beat this July I reckon. Low teens for first half of July and a washout from beginning to end. Cool temperatures and rainfall is a lot more acceptable in October than it is in July!


  • Moderators, Science, Health & Environment Moderators Posts: 16,676 Mod ✭✭✭✭Gonzo


    Autumn has arrived over the past 2 days with a very sudden drop in temperature, the temperatures over the past 2 days would give many of the warm winter of 2019/2020 daytime temperatures a run for their money in terms of cold and we're still only in September.

    It will get slightly milder over the next week but more cold plunges appear to be on the way with a northerly influence.

    ECM looks chilly and unsettled next weekend with cool north-westerlies driving in bands of cold rain. If this was December/January it could well be a fairly wintry mix. Northern blocking is trying to get going as well with the lows diving from Greenland to Ireland.

    ECMOPEU12_216_1.png

    GFS and GEM is similar with a cool/cold northwest to southeast flow dragging cool air down over Ireland.

    GFSOPEU12_210_1.png

    GEMOPEU12_216_1.png


  • Moderators, Science, Health & Environment Moderators Posts: 11,762 Mod ✭✭✭✭Meteorite58


    Yeah looks like LP over or close to us for a number of days from +120hrs.

    Unsettled.

    Breezy and at times blustery, cool and wet at times.


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  • Moderators, Science, Health & Environment Moderators Posts: 11,762 Mod ✭✭✭✭Meteorite58


    LP's continue to dominate. On the cooler side. Not too much rainfall until later in the week and then set to become very wet at times .

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  • Moderators, Science, Health & Environment Moderators Posts: 11,762 Mod ✭✭✭✭Meteorite58


    No great changes in the ECM 12Z, the main arc of the Jet below Ireland sending in the Lp's at a lower latitude than normal, on these runs France would be getting a lot of the strongest winds with extremely heavy rains. Early days yet but the models are fairly consistent that deep LP over the weekend will produce strong winds and heavy rain, will just have to keep an eye on the models and see where it tracks.

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  • Registered Users Posts: 13,477 ✭✭✭✭sryanbruen




  • Moderators, Science, Health & Environment Moderators Posts: 16,676 Mod ✭✭✭✭Gonzo


    after a relatively dry September, October is shaping up to being possibly a very wet month and the deluges are back on.

    Latest ensembles are very wet looking indeed with daily deluges starting from Wednesday. The new GFS ensembles have an extra 10 members to deal with so perhaps they are looking more over the top wet with 30 members worth of rainfall traced in these projections.

    ens_image.php?geoid=64981&var=201&run=6&date=2020-09-28&model=gfs&member=ENS&bw=1

    This is possibly one of the wettest ensembles I've seen, certainly up there with the deluges from last October and November.

    Wednesday begins this period of very wet weather.

    ECMWF_054_GB_SFC_fr-FR_fr.png

    Plenty of rain, showers and cool conditions on Thursday 1st of October

    GFSOPEU12_81_1.png

    ECMWF_090_GB_SFC_fr-FR_fr.png

    More bouts of rain over the weekend and chilly north-westerly winds pushing bands of driving rain south-eastwards across the country.

    GFSOPEU12_147_1.png

    Not much change to the end of FI at +384 hours with low pressure after low pressure, some of them possibly dartboard lows diving from the north-west across Ireland one after another and fairly windy most of the time.

    ECM broadly similar with no escape from the rain or the cool north-westerlies.

    ECMOPEU00_240_1.png

    ECMWF_168_GB_SFC_fr-FR_fr.png


  • Moderators, Science, Health & Environment Moderators Posts: 11,762 Mod ✭✭✭✭Meteorite58


    Met Eireann: 'Next Weekend: Current indications are that it will remain cool and unsettled for the weekend with showers or longer spells of rain, turning heavy at times. There is also the potential for strong winds on Sunday, particularly in the west and northwest'.

    The supporting charts.

    GFS not showing it as deep and further to the E. Potentially very wet on Sunday I would think.

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  • Moderators, Science, Health & Environment Moderators Posts: 16,676 Mod ✭✭✭✭Gonzo


    Plenty of rain over the next 10 days. Latest GFS predictions shows heaviest of the rainfall across the east with 100mm possible in many areas. These precipitation projections could increase further over the next couple of runs.

    240-777UK.GIF?29-6

    Could be fairly windy at times as well.
    138-161UK.GIF?29-6

    Temperatures below average over the next 2 weeks, especially over the next week.

    MonthlyAnomalies_T2m_20200928_w1.png

    MonthlyAnomalies_T2m_20200928_w2.png


  • Registered Users Posts: 1,483 ✭✭✭typhoony


    unusual to see ECM coming up with a cross-polar flow at this time of year, it's no good for us this time of year but at least it des transpire it will be cool and dry


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  • Moderators, Science, Health & Environment Moderators Posts: 16,676 Mod ✭✭✭✭Gonzo


    If we had this setup in the middle of January we'd certainly see a fair deal of snow, no doubt after this cold October is over and done with i'm expecting the mild south-westerlies to come back during November and December as per usual. It's been 10 years since we've had a cold December and even longer than that for a cold January.


  • Registered Users Posts: 1,030 ✭✭✭compsys


    Gonzo wrote: »
    If we had this setup in the middle of January we'd certainly see a fair deal of snow, no doubt after this cold October is over and done with i'm expecting the mild south-westerlies to come back during November and December as per usual. It's been 10 years since we've had a cold December and even longer than that for a cold January.

    Yeah - the form seems to be cool summers into early autumn and then ridiculously mild winters into early spring.


  • Registered Users Posts: 6,834 ✭✭✭pauldry


    Might be a bit different this year. We actually had our first good August in Sligo in 17 years. Well it wasnt superb but 11 or 12 days over 20c is acceptable.

    I think this Winter will see a lot of jets diving to the South and cold but then it still won't snow. It will probably be 3 or 4c and we will be asking why isnt it snowing?

    As for plus 120 weather it looks like a brutal first week of October but it may get milder mid month.


  • Moderators, Science, Health & Environment Moderators Posts: 16,676 Mod ✭✭✭✭Gonzo


    The ECM long range projections are showing a gradual return to average temperatures by the end of October and then milder than normal for first half of November indicating possibly a mild south-west flow over western Europe with cold air digging in to eastern and south-eastern parts of Europe. Sure this is a long way out and far from reliable, but hopefully it is not indicating the form over winter as it's a trend we see in reality far too often!

    Anything more than a week out is almost completely unreliable but at the same time I don't like to see this milder projections as we edge closer to the start of winter.


  • Registered Users Posts: 2,651 ✭✭✭US2


    Gonzo wrote: »
    If we had this setup in the middle of January we'd certainly see a fair deal of snow, no doubt after this cold October is over and done with i'm expecting the mild south-westerlies to come back during November and December as per usual. It's been 10 years since we've had a cold December and even longer than that for a cold January.


    January 2018 was cold ? Few morninngs of -8c I think I remember


  • Moderators, Science, Health & Environment Moderators Posts: 16,676 Mod ✭✭✭✭Gonzo


    US2 wrote: »
    January 2018 was cold ? Few morninngs of -8c I think I remember

    it was chilly at times with some frost but what I mean by a cold January is a properly cold January with snow trains rolling in off the Irish sea!


  • Registered Users Posts: 6,834 ✭✭✭pauldry


    October is the new Winter.

    Its the next normal.

    November and December are dark Springtime


  • Moderators, Science, Health & Environment Moderators Posts: 16,676 Mod ✭✭✭✭Gonzo


    pauldry wrote: »
    October is the new Winter.

    Its the next normal.

    November and December are dark Springtime

    October is beginning to look like it will be a colder than average month, we are on a north-west to south-east alignment with our weather over the next few weeks and it's possible we may still get a northerly at some point. However it does look like the jet stream is going to push north again for November with flat westerlies or mild south-westerlies taking over, but that's along way off.


  • Moderators, Science, Health & Environment Moderators Posts: 16,676 Mod ✭✭✭✭Gonzo


    Big changes appear to be on the way as the wet weather and Atlantic in general will be sent on an Autumn holiday.

    Northern blocking looks like become a big player over the next few weeks with high pressure on the cards and dryer weather.

    To begin with we pull in a very cold northerly from this weekend with winds from the Artic.

    GFSOPEU12_120_1.png

    A chilly week to follow with some frosts possible and dryer conditions but showers cannot be ruled out, particularly in northern and eastern areas as high pressure stays just out to our west. The ridge of high pressure will attempt to move in over us but remaining cold throughout.

    GFSOPEU12_213_1.png

    GFSOPEU12_312_1.png

    The high is then expected to move over to Scandinavia and this could pull in a fairly long fetch easterly from the Russian interior, frost could become fairly dominant and showers may get going across the east and this could possibly start to turn wintry over high ground, however this is a long way off..... If only this was December or January.....

    GFSOPEU12_384_1.png

    Certainly something to watch, this is really shaping up to be a colder than average October, but will it last into the winter?


  • Registered Users Posts: 16,550 ✭✭✭✭nacho libre


    October will probably be our winter. I really hope it does not turn out like last year, but once the PV gets going and the south westerlies set in we all know that's a pattern that is hard to shift.


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  • Moderators, Science, Health & Environment Moderators Posts: 16,676 Mod ✭✭✭✭Gonzo


    October will probably be our winter. I really hope it does not turn out like last year, but once the PV gets going and the south westerlies set in we all know that's a pattern that is hard to shift.

    I too am getting very worried with how cold this October is becoming, this is happening 8 to 10 weeks too early and I find it very hard to believe we can maintain this pattern into November which is still autumn, never mind the heart of winter itself.

    As we are well aware Zonal muck can go on for months and months without interruption, while winter cold spells and warm summer spells rarely last for more than one or two weeks and it's back to normal service.

    Fingers crossed if we do get the mild zonality back in November, that we can have another go at this in December or January. I'm completely fed up of cold spells happening final days of February and into March. We can still get cold during overall mild winters, even a 3 day snowy period in an overall mild winter would satisfy most people.


  • Registered Users Posts: 6,834 ✭✭✭pauldry


    90% of Decembers must be Zonal muck

    You can almost guarantee it now

    Maybe January will be unzonal muck


  • Registered Users Posts: 688 ✭✭✭bazlers


    The trends are not showing that cold. Maybe .5 to 1 degree below in some places.


  • Moderators, Science, Health & Environment Moderators Posts: 16,676 Mod ✭✭✭✭Gonzo


    bazlers wrote: »
    The trends are not showing that cold. Maybe .5 to 1 degree below in some places.

    next week could be 1 to 2 degrees below average and then the trend is to back to normal or slightly milder than average for November.

    MonthlyAnomalies_T2m_20201005_w1.png

    MonthlyAnomalies_T2m_20201005_w2.png

    Temperatures are set to become average in the second half of October so once we get next week out of the way it should start to warm up slightly.

    ens_image.php?geoid=64981&var=201&run=6&date=2020-10-07&model=gfs&member=ENS&bw=1


  • Moderators, Science, Health & Environment Moderators Posts: 11,762 Mod ✭✭✭✭Meteorite58




  • Moderators, Science, Health & Environment Moderators Posts: 11,762 Mod ✭✭✭✭Meteorite58


    More settled and less rain and wind than of late it would seem, wet and damp at times but rain looks lighter and more patchy, perhaps some cloudy days. Staying generally on the cool side, some quite cold nights perhaps leading to frosts.

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  • Moderators, Science, Health & Environment Moderators Posts: 16,676 Mod ✭✭✭✭Gonzo


    The GFS ensembles now run out to 4 weeks. The 2 weeks ensembles are still available but there is an extended option now too. Of course these would be even more unreliable than the regular 2 week ensembles but I thought it'd show it here just for fun. As they have a months worth of data they are even more tricky to read than before. This is the months trend for Dublin and it appears we keep slightly cooler than average conditions all the way into November with alot of rainfall associated with it.

    ens_image.php?geoid=64981&var=201&run=99&date=2020-10-07&model=gfs&member=ENS&bw=1

    As we move into November the precipitation remains constant but it does start to take on a sleety nature towards the end of the run during November.


  • Banned (with Prison Access) Posts: 1,075 ✭✭✭smellyoldboot


    I think I speak for all of us when I say: "BUT WILL WE HAVE A WHITE CHRISTMAS HA?"


  • Moderators, Science, Health & Environment Moderators Posts: 16,676 Mod ✭✭✭✭Gonzo


    I think I speak for all of us when I say: "BUT WILL WE HAVE A WHITE CHRISTMAS HA?"

    very, very unlikely. Even if we end up with a cold winter the chances of it snowing on Christmas Day would still be very low.


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  • Registered Users Posts: 4,164 ✭✭✭PokeHerKing


    I think I speak for all of us when I say: "BUT WILL WE HAVE A WHITE CHRISTMAS HA?"

    Pretty sure Christmas is cancelled this year anyway.


This discussion has been closed.
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