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Posted
  • Location: Camborne
  • Location: Camborne

And for some light reading during lockdown

Observational evidence of European summer weather patterns predictable from spring

Quote

Significance

Forecasts of summer weather patterns months in advance would be of great value for a wide range of applications, from tourism to agriculture, water resource management, energy production, construction, and retail. However, dynamical model seasonal forecasts for European summers have very little skill. Here, we analyze atmosphere and ocean observations and identify evidence that a specific pattern of summertime atmospheric circulation over Western Europe is predictable from the previous spring North Atlantic sea-surface temperatures, and identify the mechanism involved. The atmospheric pattern has a particularly strong influence on rainfall in the British Isles and in the north coast of France, which we find can also be predicted months ahead with significant skill.

Abstract

Forecasts of summer weather patterns months in advance would be of great value for a wide range of applications. However, seasonal dynamical model forecasts for European summers have very little skill, particularly for rainfall. It has not been clear whether this low skill reflects inherent unpredictability of summer weather or, alternatively, is a consequence of weaknesses in current forecast systems. Here we analyze atmosphere and ocean observations and identify evidence that a specific pattern of summertime atmospheric circulation––the summer East Atlantic (SEA) pattern––is predictable from the previous spring. An index of North Atlantic sea-surface temperatures in March–April can predict the SEA pattern in July–August with a cross-validated correlation skill above 0.6. Our analyses show that the sea-surface temperatures influence atmospheric circulation and the position of the jet stream over the North Atlantic. The SEA pattern has a particularly strong influence on rainfall in the British Isles, which we find can also be predicted months ahead with a significant skill of 0.56. Our results have immediate application to empirical forecasts of summer rainfall for the United Kingdom, Ireland, and northern France and also suggest that current dynamical model forecast systems have large potential for improvement.

https://www.pnas.org/content/115/1/59

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Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks

Shame my brain cells are decling so rapidly but, looking at their final comments, suggests, in spite of their optimism, the work needs improved models!

Is it not always the case?

 

 Realizing this potential will require further advances in numerical modeling and forecast systems, and in fundamental understanding of ocean–atmosphere interactions.

Edited by johnholmes
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Posted
  • Location: Camborne
  • Location: Camborne

Just been mulling over some past events as one does on a Monday morning and this was one. The unusually cold unstable sounding at Albermarle and the linear convection over the UK and snow disposition during the Beast From the East 8)

2018022812.03238.skewt_parc.thumb.gif.0c9881c97a1b3a5ac75daf49ca617b18.gifaab28-0958-b-uk.thumb.JPG.e4a6fd9336cf47ead52eb969a694047b.JPG

Edited by knocker
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Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks
1 hour ago, knocker said:

Just been mulling over some past events as one does on a Monday morning and this was one. The unusually cold unstable sounding at Albermarle and the linear convection over the UK and snow disposition during the Beast From the East 8)

2018022812.03238.skewt_parc.thumb.gif.0c9881c97a1b3a5ac75daf49ca617b18.gifaab28-0958-b-uk.thumb.JPG.e4a6fd9336cf47ead52eb969a694047b.JPG

Yes not that often one sees a DALR up to 500 mb!

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Posted
  • Location: Kirkcaldy, Fife, Scotland 20m ASL
  • Weather Preferences: Snow,Thunderstorms mix both for heaven THUNDERSNOW 😜😀🤤🥰
  • Location: Kirkcaldy, Fife, Scotland 20m ASL

Thought you might like this one @knocker 

 

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Posted
  • Location: Camborne
  • Location: Camborne

The North Atlantic 500mb and surface analysis for midnight and the 0400 UK chart

gfs-deterministic-natl_wide-z500_anom-9241600.thumb.png.cb61a55efa7b5a77ac287b2fbd9ac03c.pngPPVA89.thumb.gif.78d9e9f4808d5a497a7985f006afcedc.gif04.thumb.gif.9a423140d7c3ae2f4b58e84e851b9d47.gif

As can be seen a chilly start to the day with a fairly widespread frost and temps will remain below average through the day but with light winds not feeling too bad with plenty of sunny intervals. Maybe the odd shower over N. Ireland and the north of England but the main rain area will be over northern Scotland as the cold front slips south. Quite cold here with snow down the quite low levels.

PPVE89.thumb.gif.026a3fa58faa6a6e06aff2a1dc05aa85.gifgfs-deterministic-uk-precip_6hr_inch-9306400.thumb.png.f4585e28503347def38323fa0d7ddc92.pnggfs-deterministic-uk-t2m_c_max6-9306400.thumb.png.11e4aeafbefcff50a8c5c50798ea6865.png

Tonight the rain on the front will slowly fizzle out but a few wintry showers in the north and down the east coast

PPVG89.thumb.gif.e480bed189c9a783b6a38dbfb39f4d54.gif

The weakening front clears the south coast tomorrow and after another widespread frost a rather cold but sunny day with some showers, possibly heavy, down eastern coastal regions

PPVI89.thumb.gif.7e8e0dd9417d0e4464f6f920b14cf55f.gifgfs-deterministic-uk-t2m_c_max6-9392800.thumb.png.7a9cb6257c85648db1aa8e9f8ffa135e.png

Overnight and through Thursday the high pressure remains centred to the west of Ireland so another day of light winds and plenty of sunshine. Perhaps some patchy rain in the far north as a frontal system skirts the coast

PPVJ89.thumb.gif.64ea662eb2c260c7bb2e9b29163fc537.gifPPVK89.thumb.gif.d1324e9f618e1aec68898407e7448398.gifgfs-deterministic-uk-t2m_c_max6-9479200.thumb.png.8379aacea4f450731b9b1cb52ab515f2.png

Over friday and Saturday there is quite a lot going on with developments with the tpv lobe to the NE and another trough tracking east in the Atlantic, all of which puts the ridge under pressure. But none of this has any significant impact on the UK and a further couple of sunny days with light winds after a frosty start are on the cards and warming up a tad

gfs-deterministic-nhemi-z500_anom-9544000.thumb.png.f4266742071d1086b780914f080be916.pngPPVM89.thumb.gif.1a82dcfd3ac6249af8cf045cec733955.gifgfs-deterministic-uk-t2m_c_max6-9565600.thumb.png.4d0bf6e6041df0b7221cb146d7be5605.png

gfs-deterministic-nhemi-z500_anom-9630400.thumb.png.067ce459062c5df06244a2f08e4f6acc.pngPPVO89.thumb.gif.a9b3ed179648d23e0ad1ad80e17272cf.gifgfs-deterministic-uk-t2m_c_max6-9652000.thumb.png.09ab4e7b03dfa85b1f2ec83031adbdfb.png

 

Edited by knocker
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Posted
  • Location: Camborne
  • Location: Camborne

According to the gfs the movement of the troughs briefly brings some wet and windy weather the north on Sunday before another resurgence of the subtropical zones establishes high pressure once more over the country

gfs-deterministic-nhemi-z500_anom-9803200.thumb.png.93bcb98278a6b987555a9368b82fec37.pnggfs-deterministic-nhemi-z300_speed-9803200.thumb.png.506e8d353e930c53db02a75e81e8a35d.png

132.thumb.png.01d3dfd48a8bb38115764860f74fe6cb.pnggfs-deterministic-uk-t2m_c_max6-9738400.thumb.png.61ec4cab98c52b7794d187fbb408740a.png

156.thumb.png.253d3e08b257f926218a04ee3446091a.pnggfs-deterministic-uk-t2m_c_max6-9824800.thumb.png.4c2626ccf6767ad9dd6b064dad31d844.png

180.thumb.png.9df102c942526ca22357873fe03699e8.pnggfs-deterministic-uk-t2m_c_max6-9911200.thumb.png.2036003aad099343e37389d019a3d5e3.png

Edited by knocker
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Posted
  • Location: Camborne
  • Location: Camborne

A glance at the EC weeklies update for the last week of May and first of June

24 > 31

Still some significant subtropical high amplification in the vicinity of the UK flanked by weak tpv troughs to the east and the NW Atlantic. This portends dry and warm

ecmwf-weeklies-avg-natl_wide-z500_anom_7day-0883200.thumb.png.829efc00b42aa6aae11b0862dd1f31bc.pngecmwf-weeklies-avg-eur-t850_anom_7day-0883200.thumb.png.108b1b907fcffe59705990165c8ec2a0.pngecmwf-weeklies-avg-eur-precip_168hr_inch-0883200.thumb.png.eacfd4231e738d8d5070ed4cc6925359.png

01 > 07

The amplification subsides but still looking at quite a benign Atlantic wit positive anomalies so the indications are of a continuing slack gradient and temps above average

ecmwf-weeklies-avg-natl_wide-z500_anom_7day-1488000.thumb.png.e27f0ede674588058b97f2b3336242be.pngecmwf-weeklies-avg-eur-t850_anom_7day-0883200.thumb.png.a874e19d4a69dc0188ed5cdaf5587653.pngecmwf-weeklies-avg-eur-precip_168hr_inch-1488000.thumb.png.8d57de5bbd88183e861ea447b871c735.png

And not a grat deal of rain over the next month

ecmwf-weeklies-avg-uk-total_precip_mm-1920000.thumb.png.a477e9cc80873e503217a6066157bc4e.png

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Posted
  • Location: Camborne
  • Location: Camborne

Leaving aside the variation with the detail the ecm is on the same page as the gfs at the beginning of next week

132.thumb.png.69f87da7b24e0d8c87f8a1b7a2b77c03.pngecmwf-deterministic-uk-t2m_c_max6-9738400.thumb.png.59edaed98d269d36d9a6d225687eb27e.png

index.thumb.png.aa669bc464d704ccf0e89bdcece6fba5.pngecmwf-deterministic-uk-t2m_c_max6-9824800.thumb.png.89729329e30d064c0da8085b5df784e5.png

18-.thumb.png.bed177362875ebfef9582b60dcf29704.pngecmwf-deterministic-uk-t2m_c_max6-9911200.thumb.png.01f124675b70b50b200f155e31c2bd41.png

Edited by knocker
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Posted
  • Location: Oldham, manchester
  • Location: Oldham, manchester

Hi all. This might sound like a really daft question but im after a site or if anyone can point me in the right direction. Im after the max temp daily so far this year for a perticular place in the uk. Does anyone know where i can get this info. Tia

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Posted
  • Location: Camborne
  • Location: Camborne

Nice sat image illustrating a fair bit of cloud across central regions rain from the cold front and Lerwick in the colder showery conditions behind same

PPVA89.thumb.gif.c076f2db37eceb0acf3b903ce7f36c5a.gifsat.thumb.JPG.de5242e953766f4cee0ebd6bc1753406.JPG2020051212.03005.skewt_parc.thumb.gif.945fa847c647f46205a92565ef2aabe7.gif

 

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Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks
3 hours ago, Caz1980 said:

Hi all. This might sound like a really daft question but im after a site or if anyone can point me in the right direction. Im after the max temp daily so far this year for a perticular place in the uk. Does anyone know where i can get this info. Tia

I think it may depend on where you want the data for?

Try weather online perhaps, the Met Office; they have a long list but you need to understand the code to be able to use that.

 

Hope that may help a bit

 

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Posted
  • Location: Camborne
  • Location: Camborne

The major differences between the 00 and 06 gfs det runs start at around t144 and seem to involve the energy flows and complexity of the upper trough in mid Atlantic.As can be seen the later run has a breakaway upper trough tracking east to form another cut off low to the south of the UK courtesy of further amplification of the subtropical zones which effectively also realigns the Atlantic trough

150.thumb.png.a7fe76cfe8e7c6de43c792ffd692a07e.png174.thumb.png.48d333a7730ec0b1deb78a5780f6fb95.png

144.thumb.png.892cfe9306fa2f56e649104193e7e213.pnggfs-deterministic-natl_wide-z500_anom-0040800.thumb.png.1db0dee1b11bdbf1f0d70e03e5604afa.pnggfs-deterministic-natl_wide-z300_speed-0008400.thumb.png.44a4c1a8917e52edba9b5cceeea51149.png

Illustrated quite well by the medium term GEFS

06.thumb.png.1272cd55d6a68bd34e738b2d45c2ebed.pnggfs-ensemble-all-avg-nhemi-z500_anom_5day-0300000.thumb.png.d945db74ac66ab9b8110355bb79fed25.png

Edited by knocker
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Posted
  • Location: Camborne
  • Location: Camborne

Quite a bit of showery rain over northern Scotland  courtesy of the weakening frontal system and a fair bit of Cu running west across eastern regions in the onshore breeze with some showers along coastal fringes

PPVA89.thumb.gif.d5fbfa0a8bf5cd7cea6b088bdfb30064.gifsat.thumb.JPG.ec280827b7a2f30e89cf32b5641fdb23.JPG

Edited by knocker
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Posted
  • Location: Camborne
  • Location: Camborne

The movement of the Atlantic trough and the one to the north east, the latter phasing with low pressure in the eastern Mediterranean, promotes the subtropical to ridge north over the UK at t120 > 144/  How this translates on the surface rather dictates the regional temp variations, albeit dry

gfs-deterministic-nhemi-z500_anom-9889600.thumb.png.01b92c13057b4c6fc56ff898e607a236.png120.thumb.png.ea955dbfc479a553468689b0efbfe96f.pnggfs-deterministic-uk-t2m_c_max6-9889600.thumb.png.ec954ee52988d0f62eb8b4dfba909b94.pnggfs-deterministic-nhemi-z500_anom-9976000.thumb.png.d0333c6da0e364b37f79ee5e2e5c03be.png144.thumb.png.3359c552ba0222b504a8ff77d99463ce.pnggfs-deterministic-uk-t2m_c_max6-9997600.thumb.png.5aa6881bec4a578469ea4e66b2eb6a23.png

Edited by knocker
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Posted
  • Location: Camborne
  • Location: Camborne

Some significant differences with upper air pattern from the ecm over the same period that will obviously impact the surface analysis

ecmwf-deterministic-nhemi-z500_anom-9889600.thumb.png.45f3f1e902ba67c7a1e714828c0b269c.png120.thumb.png.6b76863d4006b3307d8f168b0bc2df10.pngecmwf-deterministic-uk-t2m_c_max6-9889600.thumb.png.256e24df916a63a9b82b09502025267b.png

ecmwf-deterministic-nhemi-z500_anom-9976000.thumb.png.e245a5f331fc11e7ce9184ea757bf88f.png144.thumb.png.fd1161b4e54ca6816a77593632851ed5.pngecmwf-deterministic-uk-t2m_c_max6-9997600.thumb.png.26a00daf1c73514a2e10dc992f507f86.png

 

Edited by knocker
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Posted
  • Location: Camborne
  • Location: Camborne

Although there are some obvious differences the NH mean anomalies this evening are all singing from the same hymn sheet.

A ridge western Russia with the tpv centred over the Arctic/northern Canada with main lobes Aleutians/northern Europe/NW Atlantic with the subtropical high amplifying between the last two north over the UK The alignment and intensity of the main players in the Atlantic/European arena, with the complicating factor of low pressure in the Mediterranean region.will determine the surface analysis applicable to the UK and this has still to be sorted. Mainly one suspects to do with regional temp variations

ecmwf-ensemble-avg-nhemi-z500_anom_5day-0321600.thumb.png.8a3f492e0d7941221d11496e5069286f.pnggfs-ensemble-all-avg-nhemi-z500_anom_5day-0321600.thumb.png.72286e15c88e6815df9149438173e7dd.png610day_03.thumb.gif.e6b8464a0da2ccff33fe4dd81388d9ea.gif

ecmwf-ensemble-avg-eur-t2m_c_anom_5day-0321600.thumb.png.e4fe964929cfcdfb125244cb924b1f64.pnggfs-ensemble-all-avg-eur-t2m_c_anom_5day-0321600.thumb.png.bd91201fe7cd8854e8fd7562fd807291.png

In the ext period the overall pattern undergoes little change apart from the intensity declining quite appreciable, albeit the GEFS hanging on to some more intense ridging over the UK

ecmwf-ensemble-avg-nhemi-z500_anom_5day-0667200.thumb.png.75b92b3a8590302b6cf78756342cc3d9.pnggfs-ensemble-all-avg-nhemi-z500_anom_5day-0667200.thumb.png.c320b35f586fb8cb70aae23db56d72a6.png814day_03.thumb.gif.70860cbec09a78d6dd36823632f5e030.gif

Notwithstanding the differences the percentage play would be pretty dry (perhaps excluding the NW) and quite warm over the whole period with plenty of sunshine

ecmwf-ensemble-avg-uk-total_precip_mm-0753600.thumb.png.dbb848ae222c5b18339ff53ded980750.pnggfs-ensemble-all-avg-uk-total_precip_mm-0753600.thumb.png.4fdeb304f221ffefdb0b8c5d2459012a.png

 

 

 

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Posted
  • Location: Camborne
  • Location: Camborne

A glance at the EC weeklies update for the first two weeks in june

01 > 08

Quite strong ridging in NW North America adjacent to a weak tpv aligned northern Russia to northern Canada. Indications across all of the Atlantic and Europe of positive anomalies suggesting that the westerly upper flow, beneath a very slack trough/ridge complex southern Greenland,will be relatively benign and thus a dry period over most of the UK and most of Europe quite toasty

ecmwf-weeklies-avg-nhemi-z500_anom_7day-1574400.thumb.png.86ad63c3433bfb654a695d64a161cb4f.pngecmwf-weeklies-avg-eur-t2m_c_anom_7day-1574400.thumb.png.410f3a7285e60f3f1d65415c3fe93a1f.pngecmwf-weeklies-avg-eur-precip_168hr_inch-1574400.thumb.png.79daecb0ca01b9bd18b956dbdd75e1d0.png

No huge changes in the following week, perhaps the weak trough to the south west becoming a tad more influential, but this leads to a slacker gradient over the UK and still dry and and quite pleasant the percentage play

ecmwf-weeklies-avg-natl_wide-z500_anom_7day-2265600.thumb.png.93133e1dacc720bef2ee6e988cd4849f.pngecmwf-weeklies-avg-eur-t2m_c_anom_7day-2265600.thumb.png.26ac616b1c86dceef56aac1bfc7421c8.pngecmwf-weeklies-avg-eur-precip_168hr_inch-2265600.thumb.png.da4b097a68fde41ef3ffaeab149f671f.png

 

 

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Posted
  • Location: Camborne
  • Location: Camborne

An overview of some of the detail Saturday > Tuesday with the ecm and the latest fax charts Fairly  obviously any inclement weather is mainly concentrated in northern and western regions

PPVG89.thumb.gif.0af2511d7c81d762c62781e5c745d971.gifecmwf-deterministic-uk-precip_12hr_inch-9652000.thumb.png.b30251aeca1ec32318941bc978002463.pngecmwf-deterministic-uk-t2m_c_max6-9652000.thumb.png.29d202428e7615767457e6a2b2763ec2.pngPPVJ89.thumb.gif.53c4b6b26c1e5892bb74393efc776053.gifecmwf-deterministic-uk-precip_12hr_inch-9738400.thumb.png.00f4bb14ee84145eadc0c214f4406384.pngecmwf-deterministic-uk-t2m_c_max6-9738400.thumb.png.b57e1df66c7dbbeb6d9c77b5f647dc73.pngPPVL89.thumb.gif.aa91148248f6d54eee8f0cfd4f02ff6b.gifecmwf-deterministic-uk-precip_12hr_inch-9824800.thumb.png.ffa80881bb7397923b5ea38801972ece.pngecmwf-deterministic-uk-t2m_c_max6-9824800.thumb.png.b32530781760381329550c2853c45195.pngPPVO89.thumb.gif.d7c85c987f17e75d27987d3e52fb0bd1.gifecmwf-deterministic-uk-precip_12hr_inch-9911200.thumb.png.c4291c0e6407834eb1496d8863c21055.pngecmwf-deterministic-uk-t2m_c_max6-9911200.thumb.png.b2a06760f12f5023c227dc18bea9de27.png

 

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Posted
  • Location: Roznava (Slovakia) formerly Hollywood, Co Wicklow
  • Weather Preferences: continental climate
  • Location: Roznava (Slovakia) formerly Hollywood, Co Wicklow

Putting this here rather then in the seasonal thread. The UKMO March update for months of APR/MAY/JUNE is failing to catch the amplified pattern in Europe. It has huge implications in my region - Slovakia. There was a huge signal of Euro high and mean SW flow with very warm anomalies here in Central Europe and further East/North East, the reality between 1st April and right through to the end of May will be the opposite and we are facing reasonably cool April/May combo. I had to cover the crops numerous times against the frost and may need to do it again next week. The same goes for Accuweather spring forecast which saw most above average temperatures in regions which will end up the coolest. Their saving grace is first half of March which was a legacy of very mild winter but boy it has flipped since. June will have to be record hot to ballance out their errors a bit. Accuweather is nailing western Europe warmth but is very poor for eastern half, the same woes it had in their winter forecast which saw eastern Europe cold that ended up the most anomalous mild

ukmo woes.PNG

download.jpg

hdgh.PNG

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