Paul

Model output discussion 8th Feb - Cold for now, but then what?

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There are a few GEFS 6z perturbations similar to the 6z operational. As I said before, there must be other models (seasonal / monthly) showing more support for cold and snow in the mid / longer range or the pros wouldn't keep mentioning it every day..anyway, I haven't given up on a proper snow fix..even late April has been known to produce a few feet of snow..1981!

11_324_850tmp.png

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Edited by Frosty.
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3 hours ago, Summer Sun said:

I would but they will still show in the quoted post below

They are updated now and positive anomalies for temps in the first three weeks. The last week is not something I personally want to see but it would be Sod's law! 

MonthlyAnomalies_T2m_20170227_w4.png

Just have to hope it is as wrong as it was in the two charts you posted earlier.

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The ECM weeklies have now updated properly a bit of a mixed back

Week 2 a touch above average but wetter

MonthlyAnomalies_T2m_20170227_w2.pngMonthlyAnomalies_Rain_20170227_w2.png

Week 4 Chiller but drier

MonthlyAnomalies_T2m_20170227_w4.pngMonthlyAnomalies_Rain_20170227_w4.png

 

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Quite a good illustration on how quickly systems are moving at the moment with troughs whipping through on the jet, Early next Saturday there is a complex area of low pressure over the UK, with some ridging to the west, which drifts east but the next low that rushes in phases in with it to form another dance of the lows on Sunday. So looking like quite a damp weekend.before the gfs has another bash at invigorating the Azores HP :shok:

gfs_ptype_slp_eur3_20.thumb.png.cacdb01b1bd9c2a4922069afe029e534.pnggfs_uv250_natl_23.thumb.png.4e4772767784089f939ea60a32692af4.pnggfs_ptype_slp_eur3_26.thumb.png.206b45d209e1f69febdd603d2f141434.png

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That's more like it! Again mid March range but the Gfs 12z ties in with the pros current thoughts 're this period, mid / late March snowfest is not out of the question. :D

12_360_mslp850.png

12_384_preciptype.png

12_384_windvector.png

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12_372_uk2mtmpmin.png

Edited by Frosty.
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GEM becomes milder as we move through next week likely to be wet at first before high pressure turns it drier for most

GEMOPEU12_168_1.thumb.png.db56c6c7919b16c6e85b0fe2c7d176bf.pngGEMOPEU12_192_1.thumb.png.aff90e1bff43057cbf84e88c8fc5df4b.pngGEMOPEU12_216_1.thumb.png.1517e9946427bda12672c253836444f7.pngGEMOPEU12_240_1.thumb.png.aa0d1b53fcc552939781f5abd7d41c48.png

GEMOPEU12_168_2.thumb.png.907db587c167fe4c57e305adcc82be5e.pngGEMOPEU12_192_2.thumb.png.f6b630f4975f4bacef40d5467b71c4a4.pngGEMOPEU12_216_2.thumb.png.58d7dc26e32ffbba4f891da75778faf6.pngGEMOPEU12_240_2.thumb.png.e055a83abba00630d7ff2b4595db20d4.png

 

 

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The GEFS still sticking to its guns as the vortex slips west

gefs_z500a_5d_nh_49.thumb.png.db659c0a6cd5075fbfa43b86ecec4ac6.png

 

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Slightly milder air moving in from the west early next week

ECMOPEU12_168_2.thumb.png.9a10d2034f291e9cdbe5021daa5a7043.pngECMOPEU12_192_2.thumb.png.b6045d5d303c9d62659a8f9e59f240e9.png

Edited by Summer Sun
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looks better by Tuesday as well SS, but sigh, settled charts always in FI 

ECM1-192.GIF?27-0

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probably the most likely result, GFS, think ECM could be wrong here

gfs-0-192.png?12

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ECM looks pleasant enough at D9

ECMOPEU12_216_2.png

@I remember Atlantic 252 Number one 1 rule never rule out ECM remember the cold snap a few weeks back? ECM was the first to downgrade it and sure enough it was right

Edited by Summer Sun
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Plenty of cold between now and 11th march for highland scotland will be good enough for me.   Not liking the sound of milder air or higher temp uppers closing in which could bring rain.

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Again there is some wintry weather on the GEFS 12z towards mid March which is the timeframe of particular interest going by the met office 're mid to late March having a chance of being cold with snow / ice and widespread frosts..P5 would suit me!:D

5_336_850tmp.png

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Edited by Frosty.
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ECM backing the weeklies update earlier for a milder week next week

ECMOPEU12_168_2.thumb.png.46ba828438994587f47324e506bd571e.pngECMOPEU12_192_2.thumb.png.314c0373ac23df26f004b9a037f9678b.pngECMOPEU12_216_2.thumb.png.f08ef04b32de393e77f845df33863bfe.pngECMOPEU12_240_2.thumb.png.fc1c7b8c61c98a6966ea5e34036f2036.png

MonthlyAnomalies_T2m_20170227_w2.png

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Yes the ecm is having a bash with the HP as well

 

ecm_t850a_5d_natl_11.png

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1 hour ago, I remember Atlantic 252 said:

looks better by Tuesday as well SS, but sigh, settled charts always in FI 

ECM1-192.GIF?27-0

Most of the GEFS ensembles tonight have that strong Iberian High. On the face of that, I'd tip my mid-range forecast from probably cooler to probably warmer.

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I know there is no cold weather showing up as we head toward Spring but it is interesting the GFS doesn't push the Atlantic past the UK when there is no real blocking to the East.

If this was depths of winter I would be excited about the possibility of a strong Arctic outbreak in 10-14 days time.

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      As ever, I will supply links to various stratospheric websites were forecasts and data can be retrieved and hope for another fascinating year of monitoring the stratosphere.
      GFS: http://www.cpc.ncep.noaa.gov/products/stratosphere/strat_a_f/
      ECM/Berlin Site: http://www.geo.fu-berlin.de/en/met/ag/strat/produkte/winterdiagnostics/index.html  
      Netweather: http://www.netweather.tv/index.cgi?action=stratosphere;sess=75784a98eafe97c5977e66aa65ae7d28
      Instant weather maps: http://www.instantweathermaps.com/GFS-php/strat.php
       NASA Merra site: http://acdb-ext.gsfc.nasa.gov/Data_services/met/ann_data.html
      Previous stratosphere monitoring threads:
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      2014/2015 https://forum.netweather.tv/topic/81567-stratosphere-temperature-watch-20142015/
      2013/2014 https://forum.netweather.tv/topic/78161-stratosphere-temperature-watch-20132014/
      2012/2013 https://forum.netweather.tv/topic/74587-stratosphere-temperature-watch-20122013/
      2011/2012 https://forum.netweather.tv/topic/71340-stratosphere-temperature-watch-20112012/
      2010/2012 https://forum.netweather.tv/topic/64621-stratosphere-temperature-watch/?hl=%20stratosphere%20%20temperature%20%20watch
      2009/2010 https://forum.netweather.tv/topic/57364-stratosphere-temperature-watch/
      2008/2009 https://forum.netweather.tv/topic/50299-stratosphere-temperature-watch/
    • By chrisbell-nottheweatherman
      Having viewed the latest longer-range Youtube video from Weatherweb (video embedded below), in which the CFS anomaly output was apparently swaying that company's thoughts regarding February's weather towards a flatter, zonal pattern), I posted the link (complete with an attempt at model-related discussion) in the relevant Model Output thread.  More than one poster remarked that, in their opinion, this model was generally inaccurate and not to be trusted.  I know that several senior posters use anomalies as a means of smoothing-out inter-run variations, so I was wondering if the CFS anomaly output is produced in a similar manner to others, and why it appears to be perceived as less useful?
       
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