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Model output discussion - 20th Feb onwards


Paul

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Posted
  • Location: Evesham/ Tewkesbury
  • Weather Preferences: Enjoy the weather, you can't take it with you 😎
  • Location: Evesham/ Tewkesbury
2 hours ago, The PIT said:

Well a downgrade on the latest gfs with the real cold uppers not making as progress down across the country. The -10c plunge never really makes it. Still going to be cold for the time of year but normal progress is to continue to downgrading so it could well end up just plain average by the time we get there.

Evening ! Downgrades /upgrades !:rofl: Some amazing cold synoptics for the time of year. News Headlines with the synoptics  we have tonight from this weekend onwards...So what weather would you like in this run? Rain ,Hail Thunder. Lightning, Sleet Snow Rain /gusty winds and even a few weak tornadoes oh yes some strong Sping sunsh[ne//////////

 

 

slimming.png

slimmingx.png

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Posted
  • Location: Cleeve, North Somerset
  • Weather Preferences: Continental winters & summers.
  • Location: Cleeve, North Somerset
14 minutes ago, ANYWEATHER said:

Evening ! Downgrades /upgrades !:rofl: Some amazing cold synoptics for the time of year. News Headlines with the synoptics  we have tonight from this weekend onwards...So what weather would you like in this run? Rain ,Hail Thunder. Lightning, Sleet Snow Rain /gusty winds and even a few weak tornadoes oh yes some strong Sping sunsh[ne//////////

 

 

slimming.png

slimmingx.png

Or just plain cold, wet and windy? Probably the most likely given that last chart. :yahoo:

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

Pretty good agreement between the ECM op and ens at d10 with winds continuing to come down from the north to north east

ECM1-240.GIF?18-0EDM1-240.GIF?18-0

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Posted
  • Location: Lincoln, Lincolnshire
  • Weather Preferences: Sunshine, convective precipitation, snow, thunderstorms, "episodic" months.
  • Location: Lincoln, Lincolnshire

As I had suspected, the ECMWF run does not show that deep low in the North Sea.

ecm500.192.png

The ECMWF run would most likely bring a mix of sunny spells and scattered wintry showers for three or four days, with the persistent rain-bearing frontal systems stuck out in the North Sea.  Wintriness in the showers would probably become restricted to northern hills by the end of the run, but potential for fairly widespread sleet/snow showers from the Midlands northwards on 26/27 April.  However, maxima on the ECMWF run would probably be rather higher than on the 12Z GFS.  The GFS 06Z run, which had us in that showery northerly, was projecting maxima between 7 and 10C (maybe even 11 or 12 in the far south-west), thanks to the strong sun at this time of year.

Tonight's UKMO run also maintains a notably wintry theme for late-April but nothing like the deep low shown by GFS.

Edited by Thundery wintry showers
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Posted
  • Location: Camborne
  • Location: Camborne

Interestingly the 6-10 anomalies tonight are in very good agreement with the upper low pretty close to southern Norway. This may well support TWSs post above with the surface low situated in the eastern North sea.

 

610day.03.gifecm_eps_z500a_5d_nh_11.pnggefs_z500a_5d_nh_41.png

 

ecm_eps_t850a_5d_eur_11.png

 

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

The latest EC32 update is not particularly enlightening in the medium term. This may possible reflect the uncertainty going forward to the middle of May.

So I'll limit this to a pretty short term update.

Next Tuesday the 26th the highly amplified upper pattern is in place with strong ridging into Greenland and the deep trough centred over Denmark. Ergo a cold northerly upper flow over the UK but rather static surface cyclonic conditions to the east with plenty of small scale detail to be resolved but the likeyhood of some quite inclement stuff, especially in the eastern half of the country. Temps well below average in the 5-7C range at 850mb but the colder air is to the E/SE.

During the next week until Tuesday May the 2nd the high amplification gradually weakens although the HP and trough remain in situ thus the upper flow backs NW with a general area of low pressure to the east.Still unsettled but temps gradually rising but still below average.

During the next week the amplification continues weakening with the flow becoming zonal and temps average but I'll leave this for now as worthwhile signals are lacking.

Back to the GFS this morning. It's bringing the low at the beginning of next week down the North Sea into Holland with some very bold temp anomalies in NW Europe. Certainly the chance of some wintry stuff down the eastern half of Britain.

gfs_t2maf_slp_eur2_27.png

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Posted
  • Location: Camborne
  • Location: Camborne

At the moment the ecm is having nothing to do with lows shooting down the North Sea at the beginning of next week. Once the northerly kicks in Sunday it maintains this for the rest of the run with the low pressure centred around Denmark.or points NE. Towards the end of the run a rogue shortwave breaks loose and runs anticlockwise ending uo north of Scotland. Anyway temps well below normal the second half of the run.

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Posted
  • Location: Kilmersdon Radstock Somerset
  • Weather Preferences: None Really but a snow lover deep down
  • Location: Kilmersdon Radstock Somerset

HERE IS MY LATEST ANALYSIS USING DATA SUPPLIED BY THE NWP OUTPUT COVERING 5 OF THE WORLDS MOST POWERFUL WEATHER COMPUTERS ISSUED AT 09:00 ON TUESDAY APR 19TH 2016

THE CURRENT GENERAL SITUATION  An anticyclone over Southern England will extend North over the next 24 hours dissolving the very weak trough straddling it across Southern Britain at the moment with an Easterly flow developing across the South tomorrow.

http://www.wetterzentrale.de/pics/Rtavn001.gif

CURRENT SNOW FORECAST AND FREEZING LEVEL OVER THE UK The freezing level across the UK will continue to rise across the UK in the coming days settling at between 5000-8000ft from tomorrow so no snowfall is expected anywhere over the next few days.

http://www.snow-forecast.com/maps/dynamic/uk

http://www.natice.noaa.gov/pub/ims/ims_gif/DATA/cursnow.gif

MODELS-2 WEEK HEADLINE  Becoming colder at the weekend with cool nights and sunshine and showers looking likely with a continuing night frost risk thereafter.

THE GFS JET STREAM FORECAST  The Southern arm of the Jet stream currently South of Spain will persist for some time while the Northern arm near Northern Scotland ridges across the Atlantic later this week and turns South down across the UK from the weekend where it remains for much of next week eventually merging with the flow well South of the UK later next week.

http://www.netweather.tv/index.cgi?action=jetstream

GFS OPERATIONAL The GFS Operational Run today shows quiet conditions for the remainder of this week although some rain on an increasing Easterly flow may reach the South towards the end of the working week. High pressure responsible for this will then move from Northern Britain out into the Atlantic and away to the NW with all eyes then to the North a s a cold and showery Northerly extends to all areas by the end of the weekend with a spell of sunshine and cold showers looking likely next week with all areas at risk with some longer spells of rain possible too especially in the East. Still cold enough for snow on northern hills and frosts at night where skies clear. There is some evidence of a recovery in temperatures towards the end of the second week as winds trend more towards the West

GFS CONTROL RUN The theme of the Control Run is pretty much the same as the cold Northerly flow next week follows this weeks quiet conditions and is subsequently succeeded by warmer winds developing across the UK towards the end of the second week.

http://www.wetterzentrale.de/pics/Rtavn1441.gif

http://www.wetterzentrale.de/pics/Rtavn3841.gif

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=144&mode=0&carte=0

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=384&mode=0&carte=0

GFS ENSEMBLE DAY 14 DATA  The GFS Clusters today are very mixed again today with everything from cold Northerlies, High pressure over the UK and Low pressure over the UK all possibilities. So the Clusters today do not seem a very worthwhile evaluation in acquiring an idea of where we might be weather-wise in two weeks.

http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=euro&MODELL=gefs&MODELLTYP=2&BASE=-&VAR=cpre&HH=372&ZOOM=0&ARCHIV=0&RES=0&WMO=&PERIOD=

UKMO The UKMO model this morning shows the slow progression of Low pressure to the East of the UK becoming the dominant feature of the weather across the UK by the end of the weekend and beginning to next week. In the meantime the current quiet and benign conditions could be interrupted by some cloud and rain in the South on Friday opening the door then to the North winds and increasing amounts of showers by the start of next week.

http://www.wetterzentrale.de/pics/Rukm1441.gif

THE FAX CHARTS The Fax Charts today agree with the theme of the Operational Run with High pressure through the week pushed out to the West by the weekend with troughs moving up from the South at the end of the working week transferred to a cold Northerly flow over the weekend with bright skies, cold winds and scattered showers, wintry on hills in the North and East.

http://www.weathercharts.org/ukmomslp.htm#t120

GEM GEM this morning also shows a largely dry and bright remainder of the week though with some rain easing into the South for a time on Friday before it becomes swept away by an increasingly cold and unstable flow from the North with showers. Then next week the run shows Low pressure close by to the UK with cool and showery weather with some longer spells of rain too and temperatures rather much on the low side of average.

http://www.wetterzentrale.de/pics/Rgem2401.gif

NAVGEM NAVGEM too shows good support for a High pressure based 3-4 days to come before a cold Northerly develops across the UK from the weekend as High pressure is forced away West and Low pressure to the East sets up a cold and showery northerly flow across the UK next week.

http://www.wetterzentrale.de/pics/Rnvg1681.gif

ECM ECM today still shows to me the least extent of cold weather next week. Although the first half of the week does show a cold and showery northerly for most it eventually cuts off the cold supply to the South entirely as the Low pressure responsible moves sufficiently West to keep winds more NW or even West later with the coldest air held away to the NW. The weather would be unsettled though with some showers for all but in the South at least this run shows the possibility of some warm sunshine between the showers in the South.

http://www.wetterzentrale.de/pics/Recm2401.gif

ECM 10 DAY MEAN (12z) The 240hr mean Chart from last night shows Low pressure over Scandinavia and High pressure over the Atlantic with a chilly North or NW flow across the UK with sunshine and showers the general theme of the chart.

http://www.wetterzentrale.de/pics/Reem2401.gif

NOTABLE TRENDS & CHANGES FROM PREVIOUS RUNS Changes are just small and subtle in the different ways in which a chilly Northerly flow is shown and as a result will likely be blowing down across the UK in the 10-14 day period.

31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The verification Statistics of GFS, UKMO and ECM show at 24 hours ECM ahead at 99.6 pts with UKMO at 99.5 pts and GFS at 99.3 pts.  At 3 days ECM is leading with 97.3 pts to UKMO's 96.7 pts while GFS lags behind at 95.5 pts. At 5 days ECM leads with 89.0 pts to UKMO at 86.6 pts and GFS at 83.4 pts. Then at 8 Days ECM has the leading spot from GFS with 64.6 pts to 57.5 pts. Finally at Day 10 ECM has the lead from GFS with a score of 44.8 pts to 38.7 pts.

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day1_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day3_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day5_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day8_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day10_PMSL_MSL_G2NHX.png

MY THOUGHTS  The theme from the models this morning is still a strong one in favour of a cold Northerly airflow to become established across the UK next week. There are some glimmers of hope though within the mix and ECM is beginning to show a way we might see just a short spell of cold Northerly winds before in the South at least things become much more modified as the coldest air is held away to the NW. This would inevitably mean that temperatures would approach normal with time and whilst not warm the sunny spells between the continuing showers would feel very welcome in temperatures closer to average. However, the rest of the output is less productive with a desire to maintain a very chilly Northerly feed across the UK for a week to 10 days at least while High pressure remains High to the west and NW. These type of spells are not that uncommon at this time of year but some of the uppers shown are certainly rather chilly for April to say the least so snow would certainly be possible over the hills though unlikely to be problematic. Frosts at night could be though as clear skies could result in some local sharp and damaging frosts for gardeners and growers so something to be aware of within the day to day forecasts next week. So while no particularly wet and windy weather to come plenty to keep us on our toes and it's probably best to enjoy the benign and pleasantly warm conditions of the next few days before temperatures set back a month or so next week.

Next Update Wednesday April 20th 2016 from 09:00

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Posted
  • Location: Darlington
  • Weather Preferences: Warm dry summers
  • Location: Darlington
2 hours ago, knocker said:

The latest EC32 update is not particularly enlightening in the medium term. This may possible reflect the uncertainty going forward to the middle of May.

So I'll limit this to a pretty short term update.

Next Tuesday the 26th the highly amplified upper pattern is in place with strong ridging into Greenland and the deep trough centred over Denmark. Ergo a cold northerly upper flow over the UK but rather static surface cyclonic conditions to the east with plenty of small scale detail to be resolved but the likeyhood of some quite inclement stuff, especially in the eastern half of the country. Temps well below average in the 5-7C range at 850mb but the colder air is to the E/SE.

During the next week until Tuesday May the 2nd the high amplification gradually weakens although the HP and trough remain in situ thus the upper flow backs NW with a general area of low pressure to the east.Still unsettled but temps gradually rising but still below average.

During the next week the amplification continues weakening with the flow becoming zonal and temps average but I'll leave this for now as worthwhile signals are lacking.

Back to the GFS this morning. It's bringing the low at the beginning of next week down the North Sea into Holland with some very bold temp anomalies in NW Europe. Certainly the chance of some wintry stuff down the eastern half of Britain.

gfs_t2maf_slp_eur2_27.png

Did the EC32 pick up the cold spell at a decent range which is coming from later this week?

Edited by Summer Sun
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Posted
  • Location: Derbyshire Peak District South Pennines Middleton & Smerrill Tops 305m (1001ft) asl.
  • Location: Derbyshire Peak District South Pennines Middleton & Smerrill Tops 305m (1001ft) asl.

The GFS continues to advertise a very cold Northerly flow by the weekend and into next week, With -7/-8/-9 uppers pushing South over UK. There will be some wonderful sunny/dry days in the clean/clear air with some sharp frosts at night.

A good week for climbing in the Highlands!

a.pngb.pngc.png

Edited by Polar Maritime
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Posted
  • Location: Camborne
  • Location: Camborne
2 hours ago, Summer Sun said:

Did the EC32 pick up the cold spell at a decent range which is coming from later this week?

I don't keep records SS but I don't remember it picking it up at the longer range but I don't have access to the full suite so I wouldn't like to be definitive about this. Certainly it picked up in the medium term as did the other anomalies.

The EPS 850mb temp and anomaly 6-10

 

ecm_eps_t850a_5d_eur_11.png

Edited by knocker
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Posted
  • Location: Darlington
  • Weather Preferences: Warm dry summers
  • Location: Darlington
14 minutes ago, knocker said:

I don't keep records SS but I don't remember it picking it up at the longer range but I don't have access to the full suite so I wouldn't like to be definitive about this. Certainly it picked up in the medium term as did the other anomalies.

The EPS 850mb temp and anomaly 6-10

 

ecm_eps_t850a_5d_eur_11.png

Thanks, hopefully it will pick up on something warmer as we move further into May

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Posted
  • Location: Cambridge, UK
  • Weather Preferences: Summer > Spring > Winter > Autumn :-)
  • Location: Cambridge, UK

ECH1-240.GIF?19-12

Northern block anybody?? That looks like it'll take some shifting....looking like early may bank holiday at least before we see any sort of change

Edited by mb018538
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Posted
  • Location: Surrey and SW France.
  • Location: Surrey and SW France.
2 hours ago, Summer Sun said:

Did the EC32 pick up the cold spell at a decent range which is coming from later this week?

Yes, at two weeks,  but not as cold as current modelling - week 3 and 4 were indistinct from base climatology. I see very basic temp and ppn anomalies on a European site.

If anybody is interested in past verification, ECM provide all the data on their site.

eg. ...  Anomalies T2m 4th to 10th April.

ps2png-atls02-95e2cf679cd58ee9b4db4dd119

http://www.ecmwf.int/en/forecasts/charts/mofc_multi/mofc_multi_verification_anomaly_family_vanomaly?time=2016040400,0,2016040400&parameter=2m%20temperature&area=Europe

 

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Posted
  • Location: Drayton, Portsmouth
  • Location: Drayton, Portsmouth
1 hour ago, mb018538 said:

ECH1-240.GIF?19-12

Northern block anybody?? That looks like it'll take some shifting....looking like early may bank holiday at least before we see any sort of change

The key for me is that Scandi low. It looks stuck with nothing to push it on. 

I do recall the GEFS being very keen on northern blocking in the D10-D15 stage at the start of this month, so credit there.

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Posted
  • Location: binley, 83 metres asl.
  • Weather Preferences: Extremes, especially heavy snow.
  • Location: binley, 83 metres asl.
5 hours ago, Polar Maritime said:

The GFS continues to advertise a very cold Northerly flow by the weekend and into next week, With -7/-8/-9 uppers pushing South over UK. There will be some wonderful sunny/dry days in the clean/clear air with some sharp frosts at night.

A good week for climbing in the Highlands!

a.pngb.pngc.png

walking wainwrights coast to coast over 10 days starting the 2nd of may. hoping to see some snow on the cumbrian fells.

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Posted
  • Location: Camborne
  • Location: Camborne

I'm wondering whether we are seeing a sign of a pattern change this evening a little sooner than expected. Both GEFS and EPS 10-15 are doing away with the amplification, no Greenland ridge, the former even has a weak trough, both keep a trough North Sea but hint at the Azores HP pushing a tad north. Ergo a more westerly flow albeit the temps still a little below average.

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Posted
  • Location: Hanley, Stoke-on-trent
  • Location: Hanley, Stoke-on-trent
4 minutes ago, knocker said:

I'm wondering whether we are seeing a sign of a pattern change this evening a little sooner than expected. Both GEFS and EPS 10-15 are doing away with the amplification, no Greenland ridge, the former even has a weak trough, both keep a trough North Sea but hint at the Azores HP pushing a tad north. Ergo a more westerly flow albeit the temps still a little below average.

Hopefully the ECM is on to something by cutting off the Northerly a little earlier. Better it was cut off altogether of course, but it's too late for that now. Such a shame to be teased with a couple of lovely days for it to be snatched away.

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Posted
  • Location: Camborne
  • Location: Camborne
Just now, davehsug said:

Hopefully the ECM is on to something by cutting off the Northerly a little earlier. Better it was cut off altogether of course, but it's too late for that now. Such a shame to be teased with a couple of lovely days for it to be snatched away.

Yup it's been wall to wall sunshine here today and hopefully the same tomorrow.

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Posted
  • Location: Camborne
  • Location: Camborne

Nothing surprising with the GFS this morning with the expected transition to cold northerlies over the weekend. This is expected to last for at least a week but perhaps a pattern change is indicated at the beginning of May with a weakening upper low to the north and the Azores HP attempting to push north mid Atlantic. Thus the upper flow backing to a much more westerly component with a subsequent rise of temps to around average,

Just a spot surface chart and the 8-13 anomaly.

gfs_t2maf_slp_eur3_26.pnggefs_z500a_5d_nh_53.png

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Posted
  • Location: Penrith Cumbria
  • Weather Preferences: Cold, snowy winters and warm sunny summers
  • Location: Penrith Cumbria

Still looks like a potent 8-10 day northerly coming up and with low pressure, low uppers below -5c and late April solar heating, I am expected some big wintry showers next week which could give temporary coverings of snow almost anywhere.

This is no two day toppler and the atmosphere will be exploding next week under such cold air and solar heating.

One for the camera I think if you like cloudscapes.

Andy

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Posted
  • Location: Kilmersdon Radstock Somerset
  • Weather Preferences: None Really but a snow lover deep down
  • Location: Kilmersdon Radstock Somerset

HERE IS MY LATEST ANALYSIS USING DATA SUPPLIED BY THE NWP OUTPUT COVERING 5 OF THE WORLDS MOST POWERFUL WEATHER COMPUTERS ISSUED AT 09:00 ON WEDNESDAY APR 20TH 2016.

THE CURRENT GENERAL SITUATION High pressure across the UK today will persist for a day or so before moving West out into the Atlantic towards the weekend. At the same time Low pressure over Spain will move slowly North pushing some troughs towards Southern England later tonight and tomorrow with a strengthening Easterly flow across the South of the UK today and tonight decreasing again on Thursday.

http://www.wetterzentrale.de/pics/Rtavn001.gif

CURRENT SNOW FORECAST AND FREEZING LEVEL OVER THE UK The freezing level across the UK is much higher than of late with values at around 5000ft in the North and to as high as 8000ft in the South for a time over the next few days. It is set to plunge to as low as 1500ft - 2000ft by the weekend.

http://www.snow-forecast.com/maps/dynamic/uk

http://www.natice.noaa.gov/pub/ims/ims_gif/DATA/cursnow.gif

MODELS-2 WEEK HEADLINE  Becoming colder at the weekend with cool nights and sunshine and showers looking likely with a continuing night frost risk thereafter. Perhaps becoming less cold as we enter May.

THE GFS JET STREAM FORECAST  The Jet Stream remains split North and South of the UK as High pressure across the UK separates the flow. As the High is pushed West out into the Atlantic the Northern arm of the flow moves South across the UK late this weekend and next week becoming a cyclonic pattern then with the Northern aspect slowly being lost with a more variable flow pattern expected late in the period.

http://www.netweather.tv/index.cgi?action=jetstream

GFS OPERATIONAL The GFS Operational Run today shows the current quiet conditions under High pressure gradually becoming replaced by a chilly Northerly flow by the weekend with some showers. This Northerly will be cold and will last a while before the flow slowly backs Westerly and become less cold later while the weather overall remains rather changeable with some rain or showers at times. 

GFS CONTROL RUN The theme of the Control Run follows the Operational to a point before it shows a build of High pressure across the UK in Week 2 with fine and sunny days under chilly nights with some frosts before a warmer Easterly flow develops towards the end of the period. 

http://www.wetterzentrale.de/pics/Rtavn1441.gif

http://www.wetterzentrale.de/pics/Rtavn3841.gif

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=144&mode=0&carte=0

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=384&mode=0&carte=0

GFS ENSEMBLE DAY 14 DATA The GFS Clusters today are once more very mixed but are less supportive of a cold Northerly now and show a very mixed set of members supporting anything between a slack and benign pressure pattern to Low pressure over Scotland with rain for all.

http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=euro&MODELL=gefs&MODELLTYP=2&BASE=-&VAR=cpre&HH=372&ZOOM=0&ARCHIV=0&RES=0&WMO=&PERIOD=

UKMO The UKMO model this morning still shows a cold pattern developing as we move through the weekend. The weather itself takes rather longer to take a turn into more unsettled mode though with the weekend apart from a few showers in the North and East largely dry with night frosts. It's not until next week when all areas look at risk of more widespread cold weather with wintry showers in a strong Northerly draught as Low pressure focuses just to the East of the UK.

http://www.wetterzentrale.de/pics/Rukm1441.gif

THE FAX CHARTS The Fax Charts today agree with the theme of the Operational Run with High pressure pulled out into the Atlantic come the weekend and a Northerly flow developing. Rain bearing troughs clear the South but we will have to watch for weak disturbances running South close to Western Britain later in the weekend in the Northerly flow delivering more cloud and some rain or even sleet on the hills.

http://www.weathercharts.org/ukmomslp.htm#t120

GEM GEM this morning shows a cold Northerly flow developing from the weekend and lasting through to the end of the run. With pressure Low to the East and High to the West the Northerly flow will promote daytime showers and in the cold air they could fall as anything including sleet or snow at times across the hills with frosts at night under clearing skies.

http://www.wetterzentrale.de/pics/Rgem2401.gif

NAVGEM NAVGEM too shows Northerly winds becoming the dominant factor in the UK weather from the weekend as the current quiet weather is sucked away out into the Atlantic. In the far South the precursor to this weather will be cloud and rain for a time on Friday before all areas stay chilly with sunshine and cold showers for the rest of the weekend and much of next week with frost at night likely. 

http://www.wetterzentrale.de/pics/Rnvg1681.gif

ECM ECM today continues to show the same drift into a cold Northerly flow as the rest of the output. However, it is looking increasingly likely that the South and West may not see too much chance of wintry showers with the focus of these towards the North and East. However, frost at night will be widespread everywhere before winds eventually back towards a Westerly point bringing less cold but changeable conditions to all areas after the turn of the month.

http://www.wetterzentrale.de/pics/Recm2401.gif

ECM 10 DAY MEAN (12z) The 240hr mean Chart from last night shows Low pressure over Scandinavia and High pressure somewhat further South over the Atlantic perhaps allowing more of a backing of wind towards the West and bringing temperatures up a bit from previous days though still with some showers across the North and East.

http://www.wetterzentrale.de/pics/Reem2401.gif

NOTABLE TRENDS & CHANGES FROM PREVIOUS RUNS Changes in the model remains small but there is a slow shift away from the coldest conditions lasting too long this morning as the theme of milder Westerly winds in 10 days increases.

31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The verification Statistics of GFS, UKMO and ECM show at 24 hours ECM ahead at 99.6 pts with UKMO at 99.5 pts and GFS at 99.3 pts.  At 3 days ECM is leading with 97.3 pts to UKMO's 96.6 pts while GFS lags behind at 95.5 pts. At 5 days ECM leads with 88.8 pts to UKMO at 86.5 pts and GFS at 83.4 pts. Then at 8 Days ECM has the leading spot from GFS with 63.6 pts to 56.0 pts. Finally at Day 10 ECM has the lead from GFS with a score of 44.8 pts to 37.1 pts.

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day1_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day3_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day5_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day8_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day10_PMSL_MSL_G2NHX.png

MY THOUGHTS There is evidence in the models this morning that the very worst of the cold weather next week may not last too long or be tempered considerably if you live towards the SW of the UK as after a few days the signs of the Northerly losing some of it's impetus is hinted at. The general pattern though remains one of cold Northerly winds enveloping the UK from the weekend. In the North and East in particular this could be come a very showery flow with sleet or snow across the hills. Further West and showers look far less frequent and there will be a lot of dry weather around. We may have to watch for weak disturbances rounding the Atlantic High and slipping South close to the west of the UK bringing some rain or sleet but away from this West looks best from midweek next week. Then as the High slips further South over the Atlantic by some models the winds begin to back more towards NW and eventually West which could cut off the cold source from the UK and bring less cold but still changeable conditions later, a fact well documented by this morning's ECM Operational Run and GFS too. So looking at all of the output in a nutshell it looks like the North and East in particular are going to feel the full blast of a late Spring Northerly blast with cold winds and April Wintry showers aplenty next week. In the West and South while colder the cold will be somewhat tempered by a lot of dry and bright weather with fewer wintry showers but all areas will likely see some unwelcome late April frosts. Then as we look to the longer term output it does appear that the trend will be towards less cold weather as we enter May under Westerly winds and occasional rainfall especially in the North in an eventually much more standard pressure pattern over and around the UK.

Next Update Thursday April 21st 2016 from 09:00

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