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December 2020 C.E.T. and EWP forecast contests -- start of the new contest year for 2020-2021


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Posted
  • Location: Rossland BC Canada
  • Location: Rossland BC Canada

    Note that the CET is also reading 6.1 to the 22nd, same information as above otherwise. 

    (current high then being 6.1 on 21st and 22nd)

    ----------------------------

    EWP current value 115 mm (109 to 21st, estimated 6 mm on 22nd and first part of today before GFS run started)

    A further 30-35 mm is indicated for the remaining 8.5 days of December (some getting 20, others 40-50).

    This adds up to around 145-150 mm which is not quite as robust as the last estimate, LG does move well up into the middle of the scoring table though.

    ------------------------------

    The CET would end up around 4.8 to 5.1 from today's temperature forecasts on GFS, the average for 23rd to 31st is 2.5, so the math on that is 

    (22 x 6.1) + (9 x 2.5) = 134.2+22.5 = 156.7 ... div by 31 = 5.055 (bound to be adjusted down at least slightly).

     

     

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    On behalf of J10 and myself, welcome to another new competition year with the winter season of 2020-21 fast (?) approaching (??). The contests will include the CET forecast and the (still optional) EW

    2.4c    52mm of snow

    Excel Spreadsheet ->  December 20 CET.xlsx SummaryPDF Format December 20 Summary.pdf Monthly Scores 3 players got 5.0c spot on. SummerShower,  Downburst and 2010cold 37 pla

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    Posted
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield
  • Weather Preferences: Any Extreme
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield

    Sunny Sheffield down to 5.5C +0.3C above normal . Rainfall now 109.9mm 126.5% of the monthly average.

    LIkely to finish just above average here temperature wise. Rainfall well above and the fifth month to do it this year. Won't be the wettest month of the year as Feb is a bit out of reach at 197mm so likely to stay the third wettest.

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    Posted
  • Location: Newcastle Upon Tyne (Spital Tongues)
  • Weather Preferences: Cold, Snow, Windstorms and Thunderstorms
  • Location: Newcastle Upon Tyne (Spital Tongues)

    Here are the latest projections. Estimate of the next 5 days from the GFS is 2.7C (values from 3 days ago in brackets).

    Dec24ProjectF.thumb.png.14da88d625f67265fb75d774a6130931.png

    Warmest: 5.8C (6.3C)
    Coldest:  4.4C (4.5C)
    Top 10:  5.8C (6.1C)
    Bottom 10:  4.7C (4.7C)
    81-10:  5.3C (5.6C)

    There is now a 31% chance of finishing close to average (between 4.1C and 5.1C), 0% chance of below average (< 4.1C) and a 69% chance of above average (> 5.1C).

    The focus has shifted a little, with 5.0C to 5.5C now the favoured provisional value with a 45.6% probability.

    Dec24probDist.thumb.png.fb0dd7b11f3c48d55df60990903f1a90.png

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    Posted
  • Location: Darlington
  • Weather Preferences: Warm dry summers
  • Location: Darlington

    6.0c to the 23rd

    1.2c above the 61 to 90 average
    1.2c above the 81 to 10 average

    ___________________________

    Current high this month 6.1c on the 22nd
    Current low this month 3.9c on the 8th & 9th

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    Posted
  • Location: Rossland BC Canada
  • Location: Rossland BC Canada

    EWP has reached 125 mm, by my estimate, 113 to 22nd, and at least 12 mm added on yesterday (a swath of 30-45 mm from south Wales to east Midlands, values as low as 5-10 mm in some other places, but also above 10 mm in the northeast -- will see tomorrow what they added on, could be more than 12).

    The 7.5 day projection from the GFS (plus any that fell earlier today) would complete the total at around 145-150 mm. Looking good for SteveB who is at the current value of 125 mm but LG still in the game, needs a finish above 162.5 to win the month, meanwhile has moved to about 15th in the current range of estimates. 

    CET heading for a landing near 5.0. 

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    Posted
  • Location: Darlington
  • Weather Preferences: Warm dry summers
  • Location: Darlington

    5.9c to the 24th

    1.1c above the 61 to 90 average
    1.1c above the 81 to 10 average

    ___________________________

    Current high this month 6.1c on the 22nd
    Current low this month 3.9c on the 8th & 9th

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    Posted
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield
  • Weather Preferences: Any Extreme
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield

    Sunny Sheffield down to 5.4C  +0.2C above normal. Rainfall up 110.2mm 126.8% of the monthly average.

    Using local forecasts as a guide we end up bang on average. They tend on the high side so average to just below looks possible now for us.

    Edited by The PIT
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  • Location: Rossland BC Canada
  • Location: Rossland BC Canada

    EWP at 128 mm now, if they add 1 mm for yesterday's rather small amounts (127 mm to 23rd). 6.5d GFS adds about 20 on average, to finish 148 mm.

    Will revise provisional scoring for 150 mm. 

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    Posted
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield
  • Weather Preferences: Any Extreme
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield

    Sunny Sheffield at 5.3C +0.2C above average. Rainfall 110.4mm 127% above normal.

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    Posted
  • Location: Darlington
  • Weather Preferences: Warm dry summers
  • Location: Darlington

    5.8c to the 25th

    1.0c above the 61 to 90 average
    1.0c above the 81 to 10 average

    ___________________________

    Current high this month 6.1c on the 22nd
    Current low this month 3.9c on the 8th & 9th

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    Posted
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield
  • Weather Preferences: Any Extreme
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield

    Sunny Sheffield at 5.2 +0.1C above normal. Rainfall 131.8mm 151.7% of the monthly average.

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    Posted
  • Location: Darlington
  • Weather Preferences: Warm dry summers
  • Location: Darlington

    5.8c to the 26th

    1.0c above the 61 to 90 average
    1.1c above the 81 to 10 average

    ___________________________

    Current high this month 6.1c on the 22nd
    Current low this month 3.9c on the 8th & 9th

    Edited by Summer Sun
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    Posted
  • Location: Windermere 120m asl
  • Location: Windermere 120m asl

    This will be one of those months when you look at the anomalies in pressure charts, and you would think that must have been a cold month, yet it will end up a little milder than average, despite a generally cold first third, and a near average last third, the much milder middle cancelling out the colder weather. An interesting month synoptic wise and very different to many recent Decembers, shades of 2008 about it, but we had colder end then.

    A sharp downturn through to the end of the month, but now probably unlikely to go below 5 degrees unless see marked downward adjustment so can't rule it out.

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  • Location: Erith. SE London/kent 40m asl
  • Weather Preferences: Winter Snow, extreme weather, mainly sunny mild summers though.
  • Location: Erith. SE London/kent 40m asl

     Need some decent frosts now and a bit of a downward correction I would think to go under the 5c, and 4 days left to achieve this, 28th to 31st. Last nights temps were on the mild side so today won’t make much of a dent in it.

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    Posted
  • Location: Windermere 120m asl
  • Location: Windermere 120m asl
    7 minutes ago, snowray said:

     Need some decent frosts now and a bit of a downward correction I would think to go under the 5c, and 4 days left to achieve this, 28th to 31st. Last nights temps were on the mild side so today won’t make much of a dent in it.

    Yes odds are we will end up with a finish in the low 5s, a very average December despite some cold weather at times. 

    There was a good chance at the mid-month point we would see our coldest December for 10 years, alas it has been mostly very mild since then, and we may well end up milder than 2014 which came in at 5.2 degrees. 2012 and 2017 finished on 4.8 degrees so we won't beat them.

    The hunt for a cold December goes on...

    Edited by damianslaw
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    Posted
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet

    So long as we are sub 5.6C we will at least be within 1C of the 1981-2010 average.

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    Posted
  • Location: Edinburgh (previously Chelmsford and Birmingham)
  • Weather Preferences: Unseasonably cold weather (at all times of year), wind, and thunderstorms.
  • Location: Edinburgh (previously Chelmsford and Birmingham)

    Wouldn't be surprised to see a finish of 5.0C (drop 0.1C per day till the 31st plus a 0.3C downward correction).

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    Posted
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield
  • Weather Preferences: Any Extreme
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield

    Sunny Sheffield still at 5.2C +0.2C above normal. Rainfall at 132.6mm 152.6% of the monthly average.

    Latest local forecast run indicate we will end up at 4.7C just 0.1C above normal.

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    Posted
  • Location: Darlington
  • Weather Preferences: Warm dry summers
  • Location: Darlington

    5.7c to the 27th

    1.0c above the 61 to 90 average
    1.0c above the 81 to 10 average

    ___________________________

    Current high this month 6.1c on the 22nd
    Current low this month 3.9c on the 8th & 9th

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    Posted
  • Location: Rossland BC Canada
  • Location: Rossland BC Canada

    EWP now close to 150 mm, the tracker had reached 146 mm after a wet day on 26th, and yesterday looks to be close to 3-4 mm additional, the 3.5d GFS forecast to end of month is rather low at 3-5 mm (a blend of some dry areas and some seeing 10 or 15 mm, most of those being in Wales and southwest to south central England). The landing point is looking close to 154 mm at this point. I will tweak the scoring summary back on page seven to reflect that, as it will move LG a few more spaces up the ranks. The next report on this barring the unforeseen will be the preliminary final value issued on 2nd of January. 

    CET can fall another 0.5 from current estimate and can be downgraded after that by 0.2-0.3 so best guess there is 4.9 to 5.2 range for the final number. Daily falls have been 0.1 recently, due to rounding we could see at least one fall of 0.2 if we get days that average below 2 C. 

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    Posted
  • Location: Coniston, Cumbria 90m ASL
  • Weather Preferences: wintry
  • Location: Coniston, Cumbria 90m ASL

    I'll be way off on EWP, but a bit closer with CET I think.

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    Posted
  • Location: Darlington
  • Weather Preferences: Warm dry summers
  • Location: Darlington

    5.6c to the 28th

    0.8c above the 61 to 90 average
    0.9c above the 81 to 10 average

    ___________________________

    Current high this month 6.1c on the 22nd
    Current low this month 3.9c on the 8th & 9th

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    Posted
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield
  • Weather Preferences: Any Extreme
  • Location: Sheffield South Yorkshire 160M Powering the Sheffield Shield

    Sunny Sheffield at 4.9C +0.1C above normal. Rainfall 138mm 158.8% above normal.

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