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damianslaw

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Posts posted by damianslaw


  1. Had hoped for some potential snow activity this evening, alas as said chances wont appear until after 2am.. not great timing a Monday night.. anyhow hoping to wake to at least some snow falling from the sky, any cover will be a bonus.. another marginal set up that could go either way. Not expecting much, just a slight cover would do.. to redeem what otherwise will end up being a snow free January.


  2. One of those instances when evaporative cooling comes into play, in heavier precipitation away from the coast and a bit of elevation, then snow could give a decent cover.. touch and go..

    Good to see reports of snow at low levels in N Ireland, that bodes well for some. I think the window for low level snow will be the depths of the night, and more so first thing around dawn..

    Pity the cold air is going to be quickly pushed aside.. still it will be nice to see the hills in white for a couple of days.


  3. 1 hour ago, philglossop said:

    Saturday 3rd February 1996, I was at the only game to survive in the whole of Devon and Cornwall football wise. Surprisingly at Tavistock FC v my team Saltash United.

     

    Never been so cold in my life at a football match, it was bitterly bitingly cold. And we lost 2-1 from memory!

    Seem to remember many FA up fourth round matches were postponed weekend 27/28th Jan.


  4. Monday night/Tuesday mornings holds interest for some snow down to low levels, FAX charts showing a small low disturbance moving through under cold enough uppers. 

    Expecting another weather warning to appear for timerange..

    In the meantime, tonight any snow most likely reserved for ground above 300 metres, but some elevations lower than this might catch in any heavy precipitation.

    Good to be able to mention snow.


  5. On 24/01/2020 at 23:12, Geordiesnow said:

     

    Looking at the shorter term prospects, subtle changes in the ECM and UKMO this evening in the 4-5 day timeframe, less influence of the azores high and more of an atlantic influence.. perhaps a sign the jet might be aligning itself on a more amplifed NW-SE position, with the end destination for heights to ridge through to the west of the UK.. marking a more concerted pattern change. GFS gets there eventually, ECM showing ridge/heights to the west building as well..

    Are we seeing signs of a weakening atlantic caused by low heights anchoring over NE USA seaboard and heights building to the west... I think perhaps so..


  6. Mmmm this January is turning into a right dull gloom fest... another overcast grey day today, light drizzle an low cloud shrouding everything - very uninspiring, expecting a quick descent into dusk probably fairly dark by half 4 unfortunately.. tomorrow looks very wet and drab again.

    Thankfully early next week will bring a shift to something much brighter thanks to polar maritime airstream, and at all long last we will start to feel the effects of increasing daylight in the afternoons I feel, after nearly 3 long months of darkness..

    The light is appearing at the end of the tunnel..


  7. Met Office forecast wordings are now so over cautious and precautionary its as if they are worried about a law suit!..

     

    A case in point current wording for Monday and Tuesday, wintry showers could fall on higher ground, it should read 'will', there is no doubt they will fall given the uppers.. I guess it depends on what the Met Office class as higher ground - would be interested to note, if they are saying 200 metres, then 'could' probably right word to use, but 500m or more which I would class as higher ground then a definate 'will' should be used. 

    I'm being very pedantic I know.

    Anyone else know what the cut off between lower levels and higher ground is???

     

    Also defintion of 'hill snow' - again what level are they talking - difficult to have a catch all I guess.. but hill snow can mean 200 metres here, whereas it can mean 400 metres in Wales.. and barely 100 metres in Scotland..


  8. 3 hours ago, Weather-history said:

    Interestingly there were three occasions when Atlantic fronts came up against a Scandi block and delivered snow in that period, one each in February, March and April.

    It wasn't a snowy spring though, spring 1995 had more days with falling snow and I have to admit I prefer that spring than this one. Spring 1996 felt like endless cloud and generally chilliness. 

    Yes, Spring 95 was quite variable, March delivered a notably snowy start to northern and western parts with frequent bands of snow from the north west, later on there was a potent northerly as well, April brought a mix of chilly showery conditions and warmer settled weather, May 95 brought a real mixed bag as well, very warm early on, cold in the middle. It marked the start of a 24 month very dry period, with the atlantic blocked, and the UK exposed to more continental influences and high pressure.

    Spring 96 conversely was consistently chilly, little warmth at all, March brought alot of easterlies, and another battleground snow event, with the cold winning out, ditto April did the same, May was very chilly, northerly and easterlies persisted until the end of the month. 

    The period Spring 95-Jan 97 reminds me a bit of the period Spring 09- Jan 11, which saw more in the way continental influence and a blocked atlantic, 1996 and 2010 were quite similiar..


  9. 50 minutes ago, Geordiesnow said:

    Problem I see is that snowfall will probably be limited to the higher ground, partly thanks to warmer than average SSTS that are no doubt around. If the - 8 hpa was forecast to hit, more would be interested but too me, snowfall looks very limited to lower levels for the most part. 

    Of course as ever the details are subject to change so any kink or trough that develops which may help to bring snowfall down to lower levels may help to increase any excitement in an otherwise underwhelming output. 

    I think the SST values to the NW are colder than average, and the source of air is coming from a cold Pole. 


  10. 5 minutes ago, Penrith Snow said:

    Wow, take a look at the ECM 240, the 1025mb isobar around the Mediterranean High stretches from the Channel Coast at Normandy to the deep Sahara, I reckon that's over 2000miles! That is one Monster Bartlett that isn't going anywhere.

    You can also bet that's one ECM 10 day chart that is sure to verify.

    Andy

    As said concentrate on the shorter term, promising for some wintry fayre around here at least.. 


  11. 19 hours ago, Interitus said:

    This graph shows the average May/June SST for the arbitrary central north Atlantic region from 1950-2019 -

    cb.thumb.png.6c9f34c34b8ae43467ee8f80e02b9e89.png

    Clearly, there has been a downward trend counter to warming elsewhere, which represents the 'cold blob'. But the decrease is not monotonic and displays much interannual/interdecadal fluctuation. Primarily the temperatures are a response to atmospheric conditions, precipitation, evaporation, insolation etc which vary with the NAO. On top of this there is infeed of currents of varying temperature and salinity into the sub-polar gyre and levels of winter deep convection overturning the static stability. To show the contrasts in temperature compare the coldest year 2015 at 9.568°C leading to the record December CET - just five years earlier the cold December was preceded by the 5th warmest SST in the series at 11.0475°C.

    Here is an interesting paper comparing the winters 2009/10 and 2010/11 and highlighting the probable importance of SST anomalies in the latter -

    https://journals.ametsoc.org/doi/full/10.1175/MWR-D-13-00104.1

    For reference, the 2009 May/June SST was cooler than average at 10.16°C which should have tended towards a warmer December.

    Interesting reading, when did the tripole develop then in 2009, through the summer and autumn? normally its SST values in May that indicate likely negative NAO or not.. I think the El Nino modoki was a strong factor for the cold winter of 09/10, it did start mild after a very mild November as well..

    2010 was cold throughout with lots of northern blocking which will have helped with warm uppers over N Atlantic.

    A blocked spring helps I think with mid atlantic heights, 1995 brought this, and we saw a tripole in winter of 95/96.. did 2005 do the same?, tripole again in winter 2005/2006.


  12. 3 hours ago, qwertyK said:

    There's no way its going to beat 1916 or 1921.

    Models predicting first few days of next week will be much colder, though most are north of the CET, with snowfall predicted.

    I'd say 2008 is the most similar year to this in terms of winter, that turned out to be 6.6. I'm guessing 6.3

    Yes strong parallels with 2008, mid-late Feb 2008 brought a long anticyclonic spell and large diurnal temp range, with some frosty nights and mild days and abundant sunshine..

    The cold arrived in time for easter and early April.. we were also I think in solar minima and crawled out of it following winter very slowly which marked a sea-change to much colder conditions... mmm... strong parallels..


  13. 3 hours ago, A Face like Thunder said:

    Like Frost Hollow's brother, I was living near Blackpool at the start of February 1996 and the snow of Monday 5th and Tuesday 6th was easily the worst in my 10 years in the area. These pictures show the scene at Cleveleys on the afternoon of Feb 5th. Perhaps not as bad as W Cumbria or SW Scotland but bad by Fylde standards, and apparently the worst there since Dec 1981. I walked to work on the 6th, but by the 7th, the snow was starting to disappear as rapidly as it came, and normal winter road conditions soon prevailed.

    The snow storm was unusual in that it affected a very thin line along the West coast of England, Scotland and Wales. January 1996 had been very cold and dry and I think it was a warm front (or occluded) which stalled over these parts which caused the problems. I remember looking east towards the Bowland fells (? 10 miles distance) and, unusually for the Fells, there was no snow on the tops at all. I also recall cancelling my participation in a weekend conference in Birmingham (having been previously stranded in the Dec 1990 snows) and being told that they had had no snow whatsoever. Such are the vagaries of the British weather!

     

    snow 5196 (1).jpg

    snow 5196 (2).jpg

    Yes it was a classic stalling battleground situation, with an occluded front grinding to a halt through SW Scotland and NW England and through west midlands. The heaviest snowfall was reserved for Dumfries and Galloway, and Cumbria and the west coast NW England next to Irish Sea. The front did move eastwards eventually but became a weaker feature and fizzled in situ, so central and eastern parts of N England didn't see much. 

    We ended up with 18 inches, the snow started about 10am 5th and didn't stop until about 4pm 6th. Great timing for school children, we were all sent home Monday afternoon and didn't return until the following Monday - I can't remember if that was half term week, I think it may have been, nearly 2 weeks off..

    Our heaviest snowfalls tend to come courtesy of similiar synoptics, a warm front moving into cold air, with a wind from the SE ahead of the front, when the cold air holds out, then the snow doesn't turn to rain.

    Not had many synoptics like it since, most fronts have moved through quicker.


  14. 6 minutes ago, s4lancia said:

    I must admit I haven't bothered looking for a few days but this is quite the change.

    Obviously not withstanding the massive failing of GEFS back in December in this respect, hopefully it is more on the ball this time around? We shall see. If so back end of Feb / early March may be our best bet for something a bit more wintery

    u_60N_10hpa_gefs.thumb.png.d01e62f16f715e82d8266ec704f66c43.png

    Been thinking back to 1995 recently and how things turned tail end Feb into March after a mostly mild Atlantic driven winter bar the odd cold snap.. early March 95 brought lots of polar air and snow for some. Not saying this will happen but there are many instances in more recent years when winter has arrived as it is ending after predominantly wet mild season.. some of the most potent cold of the year has happened then 2005, 2006, 2013, 2018...


  15. 15 minutes ago, General Cluster said:

    Too early to be greasing the skis just yet, I think...as yet another UK HP looks set to keep both the cold and the warmth elsewhere?😱

    h500slp.png    h850t850eu.png

     Shouldn't comment on long range output but that's a colder high than current one with more continental influence. The current high started off in a good position for clear conditions but alas has settled into a very poor position in this respect. Grey gloom to add to the gloomy January feeling.. 


  16. Nothing overly cold for rest of January but enough chill to prevent a finish in the 7s at least. Likely landing mark low - mid 6s.. there have been a few times recently January has been milder than December, 2018, 2014?, 2007 I think? 2005, 2002..  looking back at stats I was surprised to see 2017 and 2019 coming out at 4 degrees.. both feature as being at the colder end of January's since 1988.. 2017 I simply cant remember anything about certainly no snow or hard frost.. second half last year was frosty though with some cold days. Indeed 22 January's out of total 32 were milder.. how poor has January been for cold weather recently!


  17. 3 minutes ago, Kirkcaldy Weather said:

    @Catacol the north Pacific is definitely cooler than it was with the main warmer water area further west which has altered the storm tracks for the west / NW coast USA and Alaska 

     

    23rd December 2019 anomnight.12.23.2019.gif

    23rd January 2020

    anomnight.1.23.2020.gif

    I mentioned the persistent warm sst values n Pacific in recent winters coincided with mild here.. so interesting to note if we see colder values into next winter what effect it may have.. that's if it has any or indeed values go cold..


  18. 3 hours ago, Interitus said:

    Very interesting, but it can also tie into this other post -

     

    A couple of years back after speculation that the 'cold blob' would increase risk of early frosts and a colder winter for 2018, a rough analysis suggested that a negative May/June SST anomaly for an arbitrary 45-60°N, 10-50°W actually leads to a milder November and December, similar to the Atlantic tripole findings of Rodwell and Folland et al -

    https://www.netweather.tv/forum/topic/90431-uk-first-ground-and-air-frost-watch-season-2018-2019/?do=findComment&comment=3908027

    The source area was not optimised for correlation and also ignored any wider tripole which may explain that the cooler the blob area, the more pronounced the effect and milder the December. For the 12 coldest May/June average blob temperatures since 1950, there was only one colder than average December, 1976 (not 2009 as wrongly stated originally).

    A simple 2nd order polynomial fit for the SST data 1950-2017 gives a CET prediction of 6.0°C for Dec 2018 (actual 6.9) and 5.76°C for Dec 2019 (actual 5.8) so that's only 1 colder than average December from the 14 coldest 'blobs' and 8 of these are 6+ degC.

    At the extreme, the second coldest blob gave the second warmest December, 1974, and the coldest gave the warmest, 2015....which brings us back to the positive IOD years. 1994 fits the pattern well with its 6.4°C December following the 4th coldest blob. 1997 and 2006 however are very much in the 'warm blob' territory. A fuller analysis taking into account patterns of SST and detrending temperatures may give better results, but there do appear to be reasonable predictions available at 6/7 months in advance.

    How can the cold blob turning into a warm one then?


  19. A couple more days of anticyclonic gloom.. then a return to the westerlies, with every chance of some wintry precipitation down to relatively low levels in the north early next week - all models are showing quite cold uppers.

    A split then occurs, UKMO showing a wedge of heights behind the low, which could change the atlantic profile aligning jet on a more NW-SE angle, ECM quickly builds in azores heights but then shows a similiar scenario to UKMO - indeed a negatively tilted trough - not been able to say that all winter. GFS doesn't show the wedge just heights languishing to the south, but in far reaches does shake up the atlantic profile.

    Will be pleased to see the back of the current high - it has orientated itself in the worse position for anything sunny, cold and frosty, or even especially mild..

    Signals are also emerging that the PV is about to undergo a splintering effect, allowing perhaps more ridge/wedge development inbetween low pressures, something that hasn't been able to happen all winter so far.

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