johnholmes

Damp and misty but dry at the moment after rain overnight, a low of 6.3C, 500m at the airport, would reckon about 1000m or so here.

I tend to disagree with you CC in terms of the cold being fairly transient I think you are saying. Correct me if I am wrong. To me the turning colder starts about 4-5 days from now, nothing spectacular but certainly different in terms of temperature for areas other than central/northern Scotland over the past few weeks. If you look at the first link below, UK Met Fax output, (yes like anything else not perfect) you can see how the contour values are being lowered and the 500mb trough orientating itself more nw-se rather than w-e. http://www.weathercharts.org/ukmomslp.htm#t120 The synoptic models will continue to switch a bit for another 48 maybe 72 hours. However looking at the much less volatile anomaly charts and they show the cold setting in, contour value wise by day 5-6. With, initially, the trough the main feature as heights drop to little more than 534DM in the far south. By day 8-14 and they are shown as increasing as the upper ridge moves in thus the ridge becomes the dominant force not the trough. The 'cold' to me, in terms of afternoon values and overnight lows looks to be a coldish feature, approximately 8/9 Jan-18/19 January. Might be even more in terms of dry cold. I leave the post 2 weeks to others more qualified to suggest what may happen. IF, note IF, the upper ridge slows down allowing the surface feature beneath it to end up first of all over central UK and then maybe a touch further ne then it may delay even further the Atlantic returning. anomaly links http://www.cpc.noaa.gov/products/predictions/610day/fxus06.html http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html http://www.meteociel.fr/modeles/naefs_cartes.php?code=0&ech=240&mode=0&map=1&runpara= and to see how the MJO is looking and being predicted, GFS version http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/mjo.shtml currently 7 in reasonable orbit, and predicted to go to 8 but by then with little major impact for the 500mb anomaly charts 7 suggests as linked below So overall a very different upper air pattern for 2 weeks at least and who knows what may happen beyond this. As to when/where/how much white stuff from the sky. As always T+24h at the most on the synoptic models, and remember predicting the above in rainfall is pretty difficult, for snow, add at least 6 other parameters needed to ensure you get snow. The chief one of course no matter how cold, how low the 850's etc is for PPN to show over your back garden. enjoy the weather folks.

bit late this morning but cloudy after overnight rain and the bursts of rain and drizzle for a time, now dry but damp and dismal, low of 6.5V, now 7.6C

A brief idea from me Cold and pattern change looks very likely within 6 days to me that is using the anomaly charts. I don't pretend to know a great deal beyond 15 days. usual links http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html http://www.cpc.noaa.gov/products/predictions/610day/fxus06.html

The anomaly charts, that is NOAA 6-10 and to a lesser extent ECMWF show somewhat similar patterns and areas of +ve heights, see links below. GFS not that keen so far. It does look more likely that some kind of cold shot is developing from north of west NOT east. The 8-14 shifts the fairrly marked trough over the UK with quite low 500mb heights, well smooths it out, but also shows the +ve heights extending close into the w/nw of Scotland with much lighter 500mb winds. I would suggest a cold spell starting by day 6 but not clear how long or indeed what type it may be. Risk is over 75% I would suggest. links below http://www.cpc.noaa.gov/products/predictions/814day/500mb.php http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html this may be the 12z version of EC-GFS, not checked it, my comments were based on the 00z issue.

Cloudy but dry, a low of 3.6C

The question to ask Nick is, how likely at that time scale is this to actually happen? Will it be there at T198h, moved on of course from the actual position shown at 222h. At 240h even at 500mb any model is rarely more than 70% correct. At the surface then it is much less for such detail.

The 500mb anomaly charts I use are all reasonably consistent in the theme of a westerly flow across the Atlantic into the UK and Europe. Quite a strong flow and not mild overall with contour values below 540dm generally over the far south of the UK. No sign of any troughing down into Europe to any extent and 2 out of the 3 have no indication of +ve heights over N Norway. These +ve heights and ridging mostly extend in a swathe from the northern half of N America now into Greenland and towards the pole, although troughing is now evident in the polar areas on EC-GFS but not really on NOAA. Anyway the usual links are below. My take is this, from my daily close checks of them Sat 2 jan Ec-gfs The main changes from the charts shown above are the increase in heights towards Greenland from w/nw of there on the above charts and the replacement of the ridge n of n Norway with troughing from the flattish type of trough governing uk and European weather in the main, still low contour heights on both. Some differences but not major ones around uk or even further west. They and noaa 6-10 last night confirm the pattern will remain about w’ly 6-14 days ahead with relatively low contour heights (differences in values noaa to ec-gfs as often is the case). So remaining unsettled, even stormy perhaps at times for the NW’ern half of the UK, surface lows tracking towards NW Scotland, not mild other than as lows swing towards and extend their fronts over the UK, colder behind with a more settled short lived spell. Snow being confined, mostly, to the hills from N Wales north but some pre frontal snow to lower levels from about the same areas. No signal yet that I can see using any of the models/teleconnections available to us for any deep longer lasting cold. http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html http://www.cpc.noaa.gov/products/predictions/610day/fxus06.html

Cloudy all night with rain at times moderate before midnight, cloudy now with ocnl light rain/drizzle, a low of 6.9C, now on 8.8C

This thread would not be the same without the ray of sunshine posts from the lad Pit would they?

Cantley December 2015 Weather Summary The warmest December in my 19 years of records and also nothing as warm showed up in the RAF Finningley data from 1942-1995. Highest mean values and highest maximum value for December this month. Also a very wet month, 3 inches of rain is not that frequent here with shelter to the west. Data Mean T=9.9 (4.8) Avge Max= 11.9 (7.0), highest daytime=16.0 on 19th and coldest day=4.5 on 31st Avge Min=7.8 (2.5) with the coldest night on 13th with -1.1 and the warmest night being 19th with 12.4 Rainfall= 71.8 with the wettest day 16.4 mm on 30th; 14 days with 1.0 mm or more and 21 with 0.2 mm or more No snow (avge= 2 lying and 3 falling), fog or thunder, and 1 day with air frost (8) and 2 with ground frost (14)

Happy New Year to everone leaving the first 6 days to the synoptic topsy turvy and looking beyond. As they have pretty solidly if not totally consistently across each model output, ECMWF-GFS, NOAA, NAEFS, the anoamly charts all show a similar idea 6days out to 15 days. That is for the contours to be about westerly across the Atlantic into the UK and near Europe. All seem to show the well developed ridge centred off NE Norway to decline and move east. Heights remain relatively high across the northern swathe of the charts and relatively low in the 40-50N or so region. Thus the disturbed pattern seems set to continue for 2 weeks at least. Short spells of more settled weather behind major low surface systems. One feature that has altered over the past 4-6 days is the lowering of 500mb heights and consequent lowering of the very mild surface values in the UK. Again this looks set to continue so both wintry showers down to high ground in the Midlands area is a probability and pre frontal snow, more especially on high ground further north seems a feature in this period. Low lying snow is not likely for most places south of the Border in my view and any falling would be very brief. To me there is still no signal for longer lasting deep cold from any direction. Even trying to look beyond 15 days what few models I use and understand do not seem to me to give any solid indication of this happening. Just my take on how I see things well into January? usual links http://www.meteociel.fr/modeles/naefs_cartes.php?mode=0&code=0&ech=192&map=1&runpara= http://www.cpc.noaa.gov/products/predictions/610day/fxus06.html http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html missed the MJO=currently in 6/7 and predicted to go into very low orbit 8 http://www.americanwx.com/raleighwx/MJO/MJO/DecENMJOphase6all500mb.gif ps Just re-read this and obviously missed of the continuing rainfall totals for western areas remaining a problem, hopefully with nothing like the frequency of the past 2 weeks though. Also the wind strengths around the lows I mentioned need noting.

Happy New Year everyone A white frost in spite of thickish upper cloud layers and an air frost for the first time since 13 December, a low of -0.7C, no wind

but where please? Can you pop your nearest town in so we all know what the weather is in your locality, it really helps the enjoyment for us all. Again welcome to Net Wx.

from Google NAVGEM (Navy Global Environmental Model) is a global numerical weather prediction computer model run by NOAA. It replaced NOGAPS as the prime model in the middle of February 2013 at the FNMOC Weather model synoptic site. NOGAPS: Global weather forecast model from the "Fleet Numerical Meteorology and Oceanography Center" (USA)

some ideas net wx post 2206 30 dec 2015.doc

sorry about my brief response, but a belated welcome and as Phil has posted please have a look at the ideas in there. And DO ask questions, don't worry what others may think, we all learn in here from one another.

1 word NO

Cloudy, dry and breezy, again ridiculously mild, temperature on 13.2C from a 'low' of 10.6C

My attempt to sum up using as a start point the anomaly charts but also having looked in some detail at other outputs. I have been without any internet access other than a mobile phone for 2 days so it is not easy to pick up how any model of whatever length from T+00 has been showing. Using what is available today and comparing with my files of 2 days ago. Noaa 6-10 and it looks much as one above in most aspects, so a trough 50-60N and a ridge n of this from nw of Alaska through Greenland into northern Norway. So what will this mean at the surface=hard to be sure Generally at 500mb an atlantic flow across from the eastern seaboard, decreasing strengths as it nears the uk (especially the northern half), well really all parts other than the extreme south., ridging at 500mb north of 60N across much of northern hemisphere. This leaves me wondering just where any surface high will set up, nw of uk, n or ne? I am again far from sure where. The –ve anomaly suggests a low at 500mb and probably a surface feature beneath it sitting about 20west. Not really giving any deep cold air for the greater part of the uk. Heights over the far south shown as about 546dm, neither warm nor cold really for this time of the year, originating over southern Alaska so not really deep cold sourced. Summing up I would suggest, nothing like as mild as have had for many days. No deep cold other than fairly briefly behind surface lows that seem likely to run across the Atlantic and turn NE towards northern Scotland. Maybe another 2-3 days will make things clearer, both for the upper air pattern and where the major surface features will be? links below to anomaly charts and UK Met basic model 144h etc http://www.cpc.noaa.gov/products/predictions/814day/500mb.php http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html http://www.weathercharts.org/ukmomslp.htm other links to look at MJO was as far as I got last night, so the links will update so not sure what they are showing now, unable to do more links. Still think my summary is about right from what we have available Tue 29dec

No idea why this will not delete? unable to use PC as mouse and PC locked up after 20 mins work, tried for another 20 mins to post but no go, will try and post tomorrow, no big deal for folk but b annoying to me good night did try that L but it would not clear it, this might be my mouse issues though, currently working after a fashion but dare not trust it with copying and pasting into here which is where I was when it went awol earlier. Will try to post in the morning, as the outputs post 5 days, from any model, are very interesting. No one person will be right in their interpretation of whichever model or combination of models they use or what prediction they make from them. Interesting to try though, we all have our favourites, going before the b mouse acts up again!

Where did I make that suggestion please Mucka? I have posted with a link for folk to look at a series of charts and made a comment from my point of view not posting that there has been, I quote you above?

how about IF it will allow me to show Extra 850 mb Temperatures and isobars (the white lines) folk make up their own minds? I hope this can be allowed please Paul/team, just this once. It might help visitors/new folk see what the latest GFS is suggesting? My own view is that no sooner does it bring in lower 850 temperatures than the next surface system swings in with less cold air. Through most of its run it shows the isobars are from west to south west, rarely north west, so snow prospects away from hills and the far north look slight to me. Probably non existent for any lasting/lying variety, although the Scottish ski resorts should do quite well. no not allowed to run it but try the free version of a similar thing. link below http://www.netweather.tv/index.cgi?action=nwdc;sess=

Been unable to watch the model drama very well with no web connection for 48 hours. I would be very grateful if one of you bright chappies/chappesses could give me a BRIEF outline of where we are. Reading some comments above it might well help some of our newcomers and visitors as well. Concentrating on the next 120-144 hours really. I can do my own playing beyond that now I can see the anomaly charts, which do look interesting with heights across northern latitudes and troughs south of this going well into Europe, especially with the version from ECMWF-GFS, be interesting to see if NOAA 6-10 trends more this way this evening.

You could be correct ba but it is interesting in the, getting on for 10 years now, I have used these anomaly charts it is only in the last 12 months that I have reservations in always taking NOAA over them in terms of what is being shown.