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

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Be careful when looking at composites for MJO phasing.

Joe Bastardi tweeted something yesterday - February high amplitude phase 8 was rare in the record. That made me have a look at the years and do my own composites. The years are 2001 - 1999 - 1990 and 1988.

I've include 2008 as the CHI progression was much higher amplitude than the OLR one - not sure if that makes an overall difference.

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The composite reanalysis of the five years for February and March.

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Composites, by their nature, are a blend of the years involved but could there be a clue in the above as to what to expect in a few weeks time.

https://www.esrl.noaa.gov/psd/cgi-bin/data/composites/printpage.pl

https://www.esrl.noaa.gov/psd/data/climateindices/index.html

 

 

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following on from the comment in the previous thread re split strat vortex not verifying, I am pretty sure that the gfsp never went for this (which could be good news going into next winter) and as far as the MJO/NWP disconnect, stewart has posted on the in depth thread that we may be into phase 1 rather than 8 which explains the euro heights

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There was a post from the previous thread regarding potential temps next week saying that they were completely overblown and that a SSE wind won't deliver warmth. I don't think anyone doubted this? The higher temps correlate with a SSW feed from North Africa, which would be quite dry and mild. I don't doubt that 12-14c could be reached in this set up. If it veers back to continental only, then yes single figure maxes will be the order of the day. Direction will be everything.

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you got to think with the draw up from Africa that the figures could be met. However I am no mildy just showing the tools on UKMO...

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Edited by Jimmyh

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It has been a strange old winter thus far, all the back grounds signals have screamed cold and snow but its just never really happened apart from that small window mid Jan. its been a long hard slog looking at each model run come out and some of the eye candy has looked really good but again has failed to make it into reliable time frames. some of the posts in here have been totally stunning to read for somebody like myself still learning and trying to make sense of it all.. is winter over? nope not yet its nearly done but we all know that anything can and will happen.. March can often be a cold or very cold month and often delivers Snow for many as can April, 2012 being one such case March had record heat the first week of April totally the opposite. so while this cold spell may not be as good as was shown by the models a few days ago we all know that they can just as easy show it again in a few days time. keep up the great work in here gang. :cold-emoji:

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Cold spell into the range of the high resolution models.

 

Saturday, which is still beyond them looks the most interesting for many though.

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39 minutes ago, Dennis said:

Looks to be an interesting phase

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So, this is showing pressure higher to our north west on Sunday, whereas the models are showing it much further to the east - or am I misunderstanding it?

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just found the time to look back through the ecm, ukmo and gfs output since 1st feb and quite honestly, this idea that the ecm has been dire is misplaced. no model has been perfect (as usual). ignoring the 06z and 18z gfs runs, the 00z and 12z  show the ops in the 8/10 day period to be pretty questionable. if you had just been working from the euro models only for this upcoming period, you would have had much better expectations for what was likely and its duration.

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2 minutes ago, CK1981 said:

So, this is showing pressure higher to our north west on Sunday, whereas the models are showing it much further to the east - or am I misunderstanding it?

its at 100hpa which is the lower strat. we usually look at 500hpa in the trop for our upper pattern of ridges and troughs.

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51 minutes ago, Longtimelurker said:

Does the Greenland high look highly unlikely now?

Well, looking at the composites posted by Nouska, it looks like a phase 8 MJO in February delivers either a West based -NAO or flat zonal, so a decently placed Greenland high looks unlikely in February.

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12 minutes ago, bluearmy said:

just found the time to look back through the ecm, ukmo and gfs output since 1st feb and quite honestly, this idea that the ecm has been dire is misplaced. no model has been perfect (as usual). ignoring the 06z and 18z gfs runs, the 00z and 12z  show the ops in the 8/10 day period to be pretty questionable. if you had just been working from the euro models only for this upcoming period, you would have had much better expectations for what was likely and its duration.

thanks for that ba, I was beginning to think my memory was even worse than I thought. No one model has outshone any other but to me the ECMWF has been just a shade ahead overall, much as you seem to suggest.

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23 minutes ago, bluearmy said:

its at 100hpa which is the lower strat. we usually look at 500hpa in the trop for our upper pattern of ridges and troughs.

Thank you :-)

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45 minutes ago, MattStoke said:

Cold spell into the range of the high resolution models.

 

Saturday, which is still beyond them looks the most interesting for many though.

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The +48 chart looks like it has plenty of precip in the North Sea lined up for the South of the UK, and the wind direction looks good for that - do we think this is too light and will disperse into nothing come the weekend? 

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I was just wondering if anyone has the time to briefly outline why the MJO moving into phase 8 could promote greater amplification, or at least on a rough scale what impacts it has on the Northern Hemisphere atmospheric profile? I see people posting these MJO charts, but would like some explanation behind it please? I have tried doing some research in to it but I think it might require the summer when away from College to do that. Any response would be much welcomed :)

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26 minutes ago, johnholmes said:

thanks for that ba, I was beginning to think my memory was even worse than I thought. No one model has outshone any other but to me the ECMWF has been just a shade ahead overall, much as you seem to suggest.

Without repeating the exercise, the strange thing seemed to be that the op ecm was better days 9 and 10 and the ec mean days 6/8. Counter intuitive to say the least. And the mean Iberian surface feature was generally modelled to drift towards Italy which explains why we are seeing something rather shorter than we might have expected verify. as ever, the detail is just as relevant to our south as it is to our north - infact, when it comes to delivering pc airmasses, it could be argued moreso. 

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Yes true, I am always, even when working, suspicious of lows anywhere south of the UK, unless the Channel faster moving variety, and milder air being brought back from the Med area. This happens also even in the Channel ow mentioned above once it starts to slow down/stall over Europe.

In many ways for deep cold then the Greenland high and troughing Scandinavia/Europe is preferrable than the much sought after easterly. I actually doubt, provided the northerly creates even minor troughs (which is normally does) that most folk get more occasions of snow with this set up than the easterly type, largely, perhaps, because the former is more frequent than the latter?

Or am I totally up the wrong snowman?

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So no matter what the models are saying the met office outlook is still feeling very cold in east winds next week Perhaps some snow in the NE and in the far west becoming less cold by the 22nd but even late February in to march it's still Likely on the cold side , so they have a much better model look then we have. 

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The GEFS 6z mean shows a gradual trend to less cold conditions during next week onwards. Not saying its right, just what it shows which is a return to average conditions.

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1 hour ago, CK1981 said:

So, this is showing pressure higher to our north west on Sunday, whereas the models are showing it much further to the east - or am I misunderstanding it?

its about 15km above earth (100hpa pressure)

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      2013/2014 https://forum.netweather.tv/topic/78161-stratosphere-temperature-watch-20132014/
      2012/2013 https://forum.netweather.tv/topic/74587-stratosphere-temperature-watch-20122013/
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    • By chrisbell-nottheweatherman
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