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Posted
  • Location: Scunthorpe
  • Location: Scunthorpe
    8 hours ago, jules216 said:

    I wouldn't write of this winter just because of this QBO anomaly again. I am in the @CreweCold camp and think we are in for a good winter. We have tracking quite close to my analog years this summer of which the best are 1970,1995 and 2005. Current ACE in Atlantic and number of TS is akin to a blend of 1995 and 2005 so far and perhaps atmosphere might remember this in few months time and we will achieve at least some blocking to the north.

    I thought I would do some delving into the strength of the QBO in the autumn preceding each winter from the moment the NOAA QBO data starts to look more reliable to see what effect it has overall on the winter that follows it. 1953 looks to be the first reliable QBO data set once autumn arrives as the figures before this from 1948 to 1953 look a bit strange all hovering around -2.

    My example autumn average for 1953 looks like this

    Sep       Oct       Nov     Average

    -1.28    -0.39    -0.59    - 0.75

    We take the three figures for each of the months and add them together and divide by 3 to get the average QBO for the autumn. In this case it is -0.75 so basically neutral QBO for Autumn 1953. Obviously this figure is to be matched up with the CET values for Winter 1953/54 as follows

    Dec      Jan       Feb         Winter 1953/54

    6.9        2.9        2.6         4.13

    I have then added all December CET's from 1953 to 2019 together and divided by 67 to get the average CET for this time period and have done the same for January 1954 to January 2020 and also February 1954 to February 2020 to get the following average CET's for the whole period as follows:

                  Dec Av  Jan Av  Feb Av      Winter Av

    Av          4.89        4.15        4.21        4.42

    1953/54 6.90        2.90        2.60        4.13

    Anom     +2.01      -1.25      -1.61       -0.29

    In this specific example we had a neutral QBO which overall for this specific 1953/54 winter produced a colder than average winter overall but also a back loaded one with a very mild December followed by cold January and February too

    With my assessment I haven't shown specific winters but did group all of them related to the direction and strength of the QBO in the Autumn preceding that winter. I have categorised the QBO based on the average of the three Autumn figures as follows

    Strong EQBO          -20.00 or lower

    Moderate EQBO     -19.99 to -12.00

    Weak EQBO           -11.99 to -  4.00

    Neutral QBO           -  3.99 to + 1.99

    Weak WQBO          + 2.00 to + 5.99

    Moderate WQBO    + 6.00 to + 9.99

    Strong WQBO        +10.00 or higher

    After doing my assessment and calculations I came up with the following ordered from mildest outcome at the top to coldest outcome at the bottom

    Strong WQBO +10.00 or higher Average from Sep to Nov    11 winters in this category

    +0.44 MILDER THAN AVERAGE WITH A STRONG WQBO IN AUTUMN PRECEDING THE WINTER
    Av CET    4.89                  4.15                  4.21                  4.42
                    1953 to 2019    1954 to 2020    1954 to 2020    1953 to 2020
    Month      DEC    Anom    JAN    Anom      FEB    Anom    OVERALL    Anom
    OVERALL 5.91   +1.02    4.64   +0.49       4.05    -0.16     4.86             +0.44

    Neutral QBO   -3.99 to +1.99 Average from Sep to Nov        6 winters in this category

    +0.35 MILDER THAN AVERAGE WITH NO DOMINANT QBO IN AUTUMN PRECEDING THE WINTER
    Av CET    4.89                  4.15                  4.21                  4.42
                    1953 to 2019    1954 to 2020    1954 to 2020    1953 to 2020
    Month      DEC    Anom    JAN    Anom      FEB    Anom    OVERALL    Anom
    OVERALL 6.08   +1.19    4.17    +0.02      4.05    -0.16     4.77             +0.35

    Strong EQBO -20.00 or lower Average from Sep to Nov      11 winters in this category

    +0.16 MILDER THAN AVERAGE WITH A STRONG EQBO IN AUTUMN PRECEDING THE WINTER
    Av CET    4.89                  4.15                  4.21                  4.42
                    1953 to 2019    1954 to 2020    1954 to 2020    1953 to 2020
    Month      DEC    Anom    JAN    Anom      FEB    Anom    OVERALL    Anom
    OVERALL 5.11   +0.12    4.13    -0.02       4.49    +0.28    4.58             +0.16

    Moderate WQBO +6.00 to +9.99 Average from Sep to Nov    14 winters in this category

    +0.08 MILDER THAN AVERAGE WITH A MODERATE WQBO IN AUTUMN PRECEDING THE WINTER
    Av CET    4.89                  4.15                  4.21                  4.42
                    1953 to 2019    1954 to 2020    1954 to 2020    1953 to 2020
    Month      DEC    Anom    JAN    Anom      FEB    Anom    OVERALL    Anom
    OVERALL 4.40   -0.49     4.65    +0.50      4.44    +0.23    4.50             +0.08

    Weak EQBO -11.99 to -4.00 Average from Sep to Nov             9 winters in this category

    -0.31 COLDER THAN AVERAGE WITH A WEAK EQBO IN AUTUMN PRECEDING THE WINTER
    Av CET    4.89                  4.15                  4.21                  4.42
                    1953 to 2019    1954 to 2020    1954 to 2020    1953 to 2020
    Month      DEC    Anom    JAN    Anom      FEB    Anom    OVERALL    Anom
    OVERALL 4.57   -0.32     3.63    -0.52      4.14    -0.07      4.11             -0.31

    Moderate EQBO -19.99 to -12.00 Average from Sep to Nov  12 winters in this category

    -0.36 COLDER THAN AVERAGE WITH A MODERATE EQBO IN AUTUMN PRECEDING THE WINTER
    Av CET    4.89                  4.15                  4.21                  4.42
                    1953 to 2019    1954 to 2020    1954 to 2020    1953 to 2020
    Month      DEC    Anom    JAN    Anom      FEB    Anom    OVERALL    Anom
    OVERALL 4.38   -0.51     3.58    -0.57      4.23    +0.02     4.06             -0.36

    Weak WQBO +2.00 to +5.99 Average from Sep to Nov          4 winters in this category

    -0.74 COLDER THAN AVERAGE WITH A WEAK WQBO IN AUTUMN PRECEDING THE WINTER
    Av CET    4.89                  4.15                  4.21                  4.42
                    1953 to 2019    1954 to 2020    1954 to 2020    1953 to 2020
    Month      DEC    Anom    JAN    Anom      FEB    Anom    OVERALL    Anom
    OVERALL 3.68   -1.21     3.93    -0.22      3.43    -0.78      3.68             -0.74

    After my assessment I will go through each in turn from mildest to coldest

    MILDEST OPTION - Strong WQBO +0.44 MILDER THAN AVERAGE WITH STRONG WQBO IN AUTUMN PRECEDING THE WINTER - 11 Winters

    As I expected and many others would have expected the mildest option is a strong WQBO on average leading into the winter as a strong WQBO should in theory increase the average zonal winds so therefore lead to a more Atlantic dominated and milder winter. A couple of recent classic examples of this were also amongst the 11 winters such as 2013/14 and 2015/16 and in fact autumn 2015 had the highest average WQBO leading into the winter of +12.75. Winter 2020/21 doesn't look at this stage like it is going to be influenced by a strong WQBO in autumn 2020 unless it suddenly ramps up significantly in the next few weeks so we shouldn't have to worry about the +0.44 mild boost signal to the winter. As for individual months within the winter this setup with a strong WQBO favours a very mild start to the winter and a back loaded signal is present for cold but only slightly by the time February arrives.

    2ND MILDEST OPTION - Neutral QBO +0.35 MILDER THAN AVERAGE WITH NO QBO PHASE IN AUTUMN PRECEDING THE WINTER - 6 winters

    A rather unusual outcome came next in 2nd position and this is when there is no particular QBO phase on average in the autumn preceding the winter. Only 6 winters featured in this category and overall they come out milder than average again and have a similar pattern to the strong WQBO winters with mild weather in the December and slightly colder than average by the time February comes but what makes this option less mild than the strong WQBO option is the close to average January.

    This option is one of those that could be favoured for winter 2020/21 with the strange QBO situation we have right now and if we remain close to neutral with the QBO then it is bad news straight away with this underlying +0.35 milder signal added on before we factor anything else in.

    3RD MILDEST OPTION Strong EQBO +0.16 MILDER THAN AVERAGE WITH STRONG EQBO IN AUTUMN PRECEDING THE WINTER - 11 winters

    The third mildest option came as quite a shock to me when the strongest EQBO autumns preceding winters didn't give the very cold outcome I was expecting it to. It would seem just like any extreme version of anything a very strong signal can in fact cause a milder outcome like a strong La Nina or Super Nino seems to do. These 11 winters overall came out as milder than average by +0.16C. December was favoured to be slightly milder, January very close to average and February as the mildest of the three months but not significantly so. It certainly looks like the Strong EQBO option isn't going to feature for winter 2020/21. Maybe when the EQBO is this strong the factor that could be making these winters milder than expected is that usually when the EQBO is this strong it is at the very end of the phase and the WQBO is already descending down from above adding it's milder influence into the mix.

    4TH MILDEST OPTION - Moderate WQBO +0.08 MILDER THAN AVERAGE WITH MODERATE WQBO IN AUTUMN PRECEDING THE WINTER - 14 winters

    An expected milder than average option came in 4th position but was lower down than I expected it to be. A moderate WQBO only favours a slightly milder than average winter overall but also a front loaded winter too. December comes out at -0.49C below average on average whilst both January and February come out as milder than average, especially the January and the overall signal is only +0.08C milder. Basically a close to average winter is expected when in this QBO setup leading into the winter.

    3RD COLDEST OPTION - Weak EQBO -0.31 COLDER THAN AVERAGE WITH WEAK EQBO IN AUTUMN PRECEDING THE WINTER - 9 winters

    As expected an EQBO produces a colder outcome and with this being only weak EQBO's in autumns preceding winters then it is the least cold of the colder than average options. The weak EQBO weakens the zonal signal slightly and as a result gives a colder than average anomaly. It also favours a middle loaded winter with the coldest weather most likely in January at -0.52C below average but December and February also come out below average too. February is only slightly colder than average and this figure could have been influenced by EQBO to WQBO transitioning periods.

    2ND COLDEST OPTION - Moderate EQBO -0.36 COLDER THAN AVERAGE WITH MODERATE EQBO IN AUTUMN PRECEDING THE WINTER - 12 winters

    This option is more or less like a colder version of the weak EQBO winters with colder anomalies compared with it but the cold with the moderate EQBO winters is even more focused on the earlier winter with February close to average. Both December and January come out over -0.5C below average on average during the moderate EQBO winters. This category did also include the beast of all winters, 1962/63 which could have pulled the anomalies even colder as a result. This option looks to be off completely for winter 2020/21 but without the QBO disruption we could have had a chance to be in this moderate EQBO situation in autumn 2020.

    COLDEST OPTION - Weak WQBO -0.74 COLDER THAN AVERAGE WITH WEAK WQBO IN AUTUMN PRECEDING THE WINTER - 4 winters

    Perhaps the most shocking outcome of all was what came out coldest and by a clear margin too. The winters following an autumn with a weak WQBO. These winters were also very cold and front and back loaded with a less cold January between the two cold months of December and February. December came out a whopping -1.21C below average on average with February a still impressive -0.78C below average. January was still below average overall but by only a modest -0.22C. This category surprisingly didn't include winter 2010/11 which was in the moderate WQBO category and this makes the December average anomaly even more impressive.

    Now winter 2020/21 could easily end up falling into this category as the QBO only just recently scraped back into very weak WQBO territory but would be classed as neutral in my classification. If the WQBO gets up to around +2 to +6 then it will fit into my weak WQBO category. I'd say game on for a cold winter if that happens based on what I have analysed

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    Posted
  • Location: Crewe, Cheshire
  • Weather Preferences: Snow, storms and other extremes
  • Location: Crewe, Cheshire

    Thanks @SqueakheartLW 

    I'm of the opinion that some part of Europe will see a severe cold spell this winter- significantly below the average. I'm also plumping for a severe spell in the UK too. A very mild winter, for me, is a long odds punt.

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    Posted
  • Location: Cambridge, UK
  • Weather Preferences: Summer > Spring > Winter > Autumn :-)
  • Location: Cambridge, UK
    7 hours ago, CreweCold said:

    Thanks @SqueakheartLW 

    I'm of the opinion that some part of Europe will see a severe cold spell this winter- significantly below the average. I'm also plumping for a severe spell in the UK too. A very mild winter, for me, is a long odds punt.

    God I hope so. Last winter was really depressing. All that rain and flooding was just miserable.

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    Posted
  • Location: Scunthorpe
  • Location: Scunthorpe
    7 hours ago, CreweCold said:

    Thanks @SqueakheartLW 

    I'm of the opinion that some part of Europe will see a severe cold spell this winter- significantly below the average. I'm also plumping for a severe spell in the UK too. A very mild winter, for me, is a long odds punt.

    After 2 mild winters on the bounce, surely not a 3rd one in a row. The odds must be very much against it happening again. With no southern SSW showing up this year then that could be something to go on and should allow more stratospheric warmth to be in the northern hemisphere this winter instead of it been in the southern hemisphere.

    Also this 10 hpa easterly is really taking off now and has produced a strong easterly burst of winds at the equator over the Pacific

    Untitled2.thumb.png.6ce460f7c43a3528c580b423153151c0.png

    Just look at how vast that easterly has become. Is this a sign the EQBO is about to return to 10 hpa?

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    Posted
  • Location: Roznava (Slovakia) formerly Hollywood, Co Wicklow
  • Weather Preferences: continental climate
  • Location: Roznava (Slovakia) formerly Hollywood, Co Wicklow
    14 hours ago, SqueakheartLW said:

     

    COLDEST OPTION - Weak WQBO -0.74 COLDER THAN AVERAGE WITH WEAK WQBO IN AUTUMN PRECEDING THE WINTER - 4 winters

    Perhaps the most shocking outcome of all was what came out coldest and by a clear margin too. The winters following an autumn with a weak WQBO. These winters were also very cold and front and back loaded with a less cold January between the two cold months of December and February. December came out a whopping -1.21C below average on average with February a still impressive -0.78C below average. January was still below average overall but by only a modest -0.22C. This category surprisingly didn't include winter 2010/11 which was in the moderate WQBO category and this makes the December average anomaly even more impressive.

    Now winter 2020/21 could easily end up falling into this category as the QBO only just recently scraped back into very weak WQBO territory but would be classed as neutral in my classification. If the WQBO gets up to around +2 to +6 then it will fit into my weak WQBO category. I'd say game on for a cold winter if that happens based on what I have analysed

    @SqueakheartLW May I ask what 4 winters are in the Coldest Option? Just wondering if any of those match my summer analogs - 1970,1977,1995,2005 and 2010. Many thank.J

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    Posted
  • Location: Scunthorpe
  • Location: Scunthorpe
    8 hours ago, jules216 said:

    @SqueakheartLW May I ask what 4 winters are in the Coldest Option? Just wondering if any of those match my summer analogs - 1970,1977,1995,2005 and 2010. Many thank.J

    Winter 1995/1996 is amongst the 4 winters featured as well as another cold classic 1978/1979. The two winters that could put the cold theory in jeopardy are 1992/1993 and 1973/1974 but overall when these winters are averaged out the anomalies come out colder than average for all 3 winter months. I imagine averaging out the winters helps to remove other factors at play during those winters and should result in the underlying QBO signal as a common factor with all of the winters. The data is below:

                                               Average CET 1953 to 2020           DEC - 4.89C    JAN - 4.15C    FEB - 4.21C     WINTER - 4.42C
                                           QBO Figures                         CET     1953 to 2019   1954 to 2020   1954 to 2020    1953 to 2020
    Autumn Weak WQBO   Sep     Oct      Nov    AV        Winter   DEC    Anom    JAN    Anom    FEB    Anom    OVERALL    Anom
                               1995   + 6.98 + 3.43 - 0.77 + 3.21  1995/96  2.30C -2.59C  4.30C +0.15C  2.50C  -1.71C   3.03C         -1.39C
                               1992   + 1.30 + 3.94 + 6.33+ 3.86  1992/93  3.60C -1.29C  5.90C +1.75C 4.60C   +0.39C  4.70C         +0.28C
                               1973   + 5.51 + 5.20 + 4.92+ 5.21  1973/74  4.90C +0.01C 5.90C +1.75C 5.40C   +1.19C  5.40C         +0.98C
                               1978   + 5.91 + 6.22 + 4.04+ 5.39  1978/79  3.90C -0.99C -0.40C  -4.55C 1.20C   -3.01C   1.57C         -2.85C
                                                                                  AVERAGE  3.68C -1.21C  3.93C  -0.22C 3.43C   -0.78C   3.68C         -0.74C

    Edited by SqueakheartLW
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    Posted
  • Location: Scunthorpe
  • Location: Scunthorpe

    There may be some hope for those out there who want to see a return of the EQBO

    Take a look at the following chart

    qbo.thumb.jpg.89570b7bceab13ffa5114770627f4042.jpg

    1 - After the initial descent of the new easterly phase from 3 to 7 hpa things look to be stalling for a while and during this period I was getting the feeling that this was the end of any chances of the EQBO coming back and we were going to be heading into another probable year of the WQBO again and therefore thought we was going to suffer the prospect of yet another WQBO driven winter for 2020/21

    2 - However the last couple of days has started to change my mind. Look within my green circle and you may be able to make out that the neutral/ weak easterly area has suddenly started to descend again and quite rapidly too and if you look closely you can see how it has dropped right down to around 15 hpa. This has got my hopes up of a return of the EQBO to the areas from 15hpa and upwards and with the continuing descent and weakening of the anomalous easterlies below 60 hpa then this could be a sign that the EQBO is on the way back after all. However it is highly unlikely that it will descend down to 30 hpa in time for the winter.

    This general increase in easterlies can be confirmed with the following chart

    Untitled.thumb.jpg.3c850f3e5b1e8e4562e0bfee39af5054.jpg

    The area within my green circle on this chart was mostly westerlies just a few weeks ago. Now there's only one tiny patch of westerlies still remaining and the rest is now a sea of blue between 15 hpa and 1 hpa.

    Watch this space and hope that in a week or two the EQBO is on the way back

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    Posted
  • Location: Scunthorpe
  • Location: Scunthorpe
    17 hours ago, sebastiaan1973 said:

    And yesterday. Seems to me in 10 days time the westerlies will return in the 'green area.'

    ecmwfzm_u_a12.png

    Maybe westerlies do return to the areas around 10 to 20 S but notice what the forecast also shows for the regions above the equator itself

    ecmwfzm_u_a12.thumb.jpg.47374c1d42a7035ca3507f63e561764e.jpg

    1 - The current situation shows the new EQBO has descended to around 7 hpa. This region lacked any easterlies at all from 1 hpa to 7 hpa only a few weeks ago. Now look at the forecast for 240 hours time

    ecmwfzm_u_f240.thumb.jpg.bf4da9f814398507c9476d3633225338.jpg

    2 - Notice how the EQBO is predicted to have got down to 10 hpa and there's every chance that it will only strengthen from that point onward. There is also a general weakening of the easterlies below 60 hpa too which should be a good sign for the EQBO. The westerlies at 30 hpa look to descend a bit too over the period.

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    Posted
  • Location: Cambridge, UK
  • Weather Preferences: Summer > Spring > Winter > Autumn :-)
  • Location: Cambridge, UK
    54 minutes ago, sebastiaan1973 said:

    Glosea5 update shows a strong high at the coast of Alaska. Positive NAO. Once again.

    2cat_20200801_mslp_months46_global_deter_public.png

    So basically every UK winter then. Zonal, wet and windy. These can be wrong though!

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    Posted
  • Location: Scunthorpe
  • Location: Scunthorpe
    3 hours ago, sebastiaan1973 said:

    Glosea5 update shows a strong high at the coast of Alaska. Positive NAO. Once again.

    2cat_20200801_mslp_months46_global_deter_public.png

    They seem to put that "Ridiculously Resilient Ridge" in EVERY winter now as a default. Great news if you want cold in the USA in winter but bad news for every other northern hemisphere location. All the cold end up bottled up over Greenland, Canada and for large parts of the time the USA too. The usual downstream pattern is the Euro slug that leaves us in S or SW winds all winter and variations on the 2013/14, 2019/20 and December 2015 themes.

    Just as long as we don't end up with another polar vortex of doom like we had last winter, that vortex was about as extreme as it gets in the northern hemisphere.

    Notice all that high pressure in the eastern Pacific in general. Is that La Nina related?

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  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet
    3 hours ago, SqueakheartLW said:

    They seem to put that "Ridiculously Resilient Ridge" in EVERY winter now as a default. Great news if you want cold in the USA in winter but bad news for every other northern hemisphere location. All the cold end up bottled up over Greenland, Canada and for large parts of the time the USA too. The usual downstream pattern is the Euro slug that leaves us in S or SW winds all winter and variations on the 2013/14, 2019/20 and December 2015 themes.

    Just as long as we don't end up with another polar vortex of doom like we had last winter, that vortex was about as extreme as it gets in the northern hemisphere.

    Notice all that high pressure in the eastern Pacific in general. Is that La Nina related?

    Yes, Nina tends to encourage a -EPO and -PNA which are indicated on that chart. 

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    Posted
  • Location: Ludgershall, Wiltshire
  • Location: Ludgershall, Wiltshire
    On 12/08/2020 at 10:04, sebastiaan1973 said:

    Glosea5 update shows a strong high at the coast of Alaska. Positive NAO. Once again.

    2cat_20200801_mslp_months46_global_deter_public.png

    That would be down to the warm anomalies in the north east Pacific which have been a semi permanent feature since 2014 and really need to do one if are to be in with a good chance of a cold winter.  North America is the place to be for cold winters right now.

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    Posted
  • Location: Scunthorpe
  • Location: Scunthorpe

    Here's a promising start if you are hoping for a cold winter 2020/21

    u10serie.thumb.png.8fca190288e0805a4a71e5733974e8bf.png

    Every single one of the CFS runs is below the long term average for zonal winds and all significantly below 2019 at the same stage of the year. Wouldn't take much really since it was a polar vortex of doom after all.

    These runs tie in with the general themes from the main long range CFS runs. These are my totals so far from the daily runs I have looked at

    CFS 00Z 500hpa anomalies    Start 06/07/2020    Last 15/08/2020

    Temps        Nov       Dec     Jan      Feb         Mar
    V Mild           0           1         0          1             0
    Mild             12         10        7           7            7
    Average      13          11       17        15           22
    Cold            16          19      17         15           10
    V Cold          0           0         0          3             2
    LEADER     COLD COLD AV/CD AV/CD AVERAGE

    Precip        Nov      Dec          Jan        Feb         Mar
    V Dry           0           0             1             1             0
    Dry              13         22            8            8             7
    Average       20         9            16          12           16
    Wet              7          10           15          16           15
    V Wet          1           0             1             4            3
    LEADER    AVER AV/WET AV/WET    WET    AV/WET

    Not looking good if you want a dry winter but since most options are average temperatures or colder then there's every hope that with the wetter than average signal combining with a colder than average one that a fair few of these wetter spells could have snow involved in them.

    There is a clear front loaded winter signal beginning to emerge too as these runs progress too. Maybe ties in well with the CFS zonal wind forecast.

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  • Location: Wantage, Oxon
  • Weather Preferences: Hot, cold!
  • Location: Wantage, Oxon
    1 hour ago, SqueakheartLW said:

    Here's a promising start if you are hoping for a cold winter 2020/21

    u10serie.thumb.png.8fca190288e0805a4a71e5733974e8bf.png

    Every single one of the CFS runs is below the long term average for zonal winds and all significantly below 2019 at the same stage of the year. Wouldn't take much really since it was a polar vortex of doom after all.

    These runs tie in with the general themes from the main long range CFS runs. These are my totals so far from the daily runs I have looked at

    CFS 00Z 500hpa anomalies    Start 06/07/2020    Last 15/08/2020

    Temps        Nov       Dec     Jan      Feb         Mar
    V Mild           0           1         0          1             0
    Mild             12         10        7           7            7
    Average      13          11       17        15           22
    Cold            16          19      17         15           10
    V Cold          0           0         0          3             2
    LEADER     COLD COLD AV/CD AV/CD AVERAGE

    Precip        Nov      Dec          Jan        Feb         Mar
    V Dry           0           0             1             1             0
    Dry              13         22            8            8             7
    Average       20         9            16          12           16
    Wet              7          10           15          16           15
    V Wet          1           0             1             4            3
    LEADER    AVER AV/WET AV/WET    WET    AV/WET

    Not looking good if you want a dry winter but since most options are average temperatures or colder then there's every hope that with the wetter than average signal combining with a colder than average one that a fair few of these wetter spells could have snow involved in them.

    There is a clear front loaded winter signal beginning to emerge too as these runs progress too. Maybe ties in well with the CFS zonal wind forecast.

    Thanks, good analysis, obviously with caveat it is CFS...but with the solar minimum I would like to see a higher probability this year of colder weather in the seasonal models as we approach winter.  Would be happier if the QBO would sort itself out!

    Edited by Mike Poole
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  • Location: Cambridge, UK
  • Weather Preferences: Summer > Spring > Winter > Autumn :-)
  • Location: Cambridge, UK

    The CFS has a known weaker vortex forecast bias at longer lead times, I wouldn't read too much into that. 

    If you check out Simon Lees excellent site, there is loads more information and data about the PV etc.

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  • Location: Coniston, Cumbria 90m ASL
  • Weather Preferences: wintry
  • Location: Coniston, Cumbria 90m ASL
    14 hours ago, mb018538 said:

    The CFS has a known weaker vortex forecast bias at longer lead times, I wouldn't read too much into that. 

    If you check out Simon Lees excellent site, there is loads more information and data about the PV etc.

    Any chance of a link please?

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  • Location: Scunthorpe
  • Location: Scunthorpe
    On 08/08/2020 at 16:34, sebastiaan1973 said:

    Well, this is the forecast. 

    ecmwfzm_u_f240.png

    Remember this forecast you showed a few days ago showing 17/08/2020

    Here is the actual reading from 17/08/2020 for comparison

    ecmwfzm_u_a12.thumb.png.0f5f14dd773f9a95071910d507533666.png

    Has less westerlies than was forecast 10 days ago and the easterlies both above 7 hpa and just south of the equator are stronger too. Maybe not such bad news if you are like me and want to see a return of the EQBO rather than a full failure and resumption of the WQBO for another year at least

    Edited by SqueakheartLW
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  • Location: New Ash green 150M / 500 FT
  • Location: New Ash green 150M / 500 FT

    Updated QBO chart for mid August sees negative ( Easterly ) Winds down to about 5HPA..

    The increments of negativity are in 5M/S so we can see 10HPA is just tipping into negative, 5HPA is about -5M/S which quickly traverses to ~-30 M/S at 3 HPA.

    The start of December is 14 weeks away which is just enough time to see some stronger values downwell ...

    Perhaps for once some good news....

    06DE6082-119A-42F2-8F5E-6B4E46E6A90B.thumb.png.ed66a8537d556e8ef857a2d89378d6c3.png

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  • Location: Cambridge, UK
  • Weather Preferences: Summer > Spring > Winter > Autumn :-)
  • Location: Cambridge, UK
    1 hour ago, Steve Murr said:

    Updated QBO chart for mid August sees negative ( Easterly ) Winds down to about 5HPA..

    The increments of negativity are in 5M/S so we can see 10HPA is just tipping into negative, 5HPA is about -5M/S which quickly traverses to ~-30 M/S at 3 HPA.

    The start of December is 14 weeks away which is just enough time to see some stronger values downwell ...

    Perhaps for once some good news....

    06DE6082-119A-42F2-8F5E-6B4E46E6A90B.thumb.png.ed66a8537d556e8ef857a2d89378d6c3.png

    Think it will make it down? Or another false dawn?

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  • Location: New Ash green 150M / 500 FT
  • Location: New Ash green 150M / 500 FT
    10 minutes ago, mb018538 said:

    Think it will make it down? Or another false dawn?

    Not sure yet --- so far the cycle of failures has only been 1 at a time so probably unlikely to fail 2 times on the trott! 

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